Package Torello.Java

Class StringParse

  • public class StringParse
extends java.lang.Object
    StringParse - Documentation.

    These are some commonly used helper functions that were utilized when the project began. As the project grows more java.lang.String Utilities are added, here and there. Likely, there are probably methods that exist in libraries available somewhere in someone else' jar files. Possibly Apache Commons has a method similar to StringParse.leftSpacePad(...) - but since the complete set of Helper Utilities that are provided in package Torello.Java.*; are very detailed and numerous, home grown helper and utility functions are used, rather than trying to figure out Apache, or other's jar-libraries. Quite a number of these really just seem like naming conventions for properly formatted dates and times that avoid getting too complicated with Java's class 'Calendar' or Java's java.text.* package.

    Static (Functional) API: The methods in this class are all (100%) defined with the Java Key-Word / Key-Concept 'static'. Furthermore, there is no way to obtain an instance of this class, because there are no public (nor private) constructors. Java's Spring-Boot, MVC feature is *not* utilized because it flies directly in the face of the light-weight data-classes philosophy. This has many advantages over the rather ornate Component Annotations (@Component, @Service, @AutoWired, etc... 'Java Beans') syntax:

    • The methods here use the key-word 'static' which means (by implication) that there is no internal-state. Without any 'internal state' there is no need for constructors in the first place! (This is often the complaint by MVC Programmers).
    • A 'Static' (Functional-Programming) API expects to use fewer data-classes, and light-weight data-classes, making it easier to understand and to program.
    • The Vectorized HTML data-model allows more user-control over HTML parse, search, update & scrape. Also, memory management, memory leakage, and the Java Garbage Collector ought to be intelligible through the 'reuse' of the standard JDK class Vector for storing HTML Web-Page data.

    The power that object-oriented programming extends to a user is (mostly) limited to data-representation. Thinking of "Services" as "Objects" (Spring-MVC, 'Java Beans') is somewhat 'over-applying' the Object Oriented Programming Model. Like most classes in the Java-HTML JAR Library, this class backtracks to a more C-Styled Functional Programming Model (no Objects) - by re-using (quite profusely) the key-word static with all of its methods, and by sticking to Java's well-understood class Vector

    Static Fields: The methods in this class do not create any internal state that is maintained - however there are a few private & static fields defined. These fields are instantiated only once during the Class Loader phase (and only if this class shall be used), and serve as data 'lookup' fields (static constants). View this class' source-code in the link provided below to see internally used data.

    This class maintains a few public, static regular-expression constants, and also a few protected static final String[] array's which are strictly used as constants by the methods in this class in order to computing results. There is also a static final java.text.DecimalFormat instance to format numbers.



    • Field Detail

      • WHITE_SPACE_REGEX

        public static final java.util.regex.Pattern WHITE_SPACE_REGEX
        This regular expression simply matches white-space found in a java String.
        See Also:
        removeWhiteSpace(String)
        Code:
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        public static final Pattern WHITE_SPACE_REGEX = Pattern.compile("\\s+");

      • NUMBER_COMMMA_REGEX

        public static final java.util.regex.Pattern NUMBER_COMMMA_REGEX
        This regular expression is used for integer and floating-point numbers that use the comma (',') between the digits that comprise the number. For example, this Regular Expression would match the String "900,800,75.00".
        See Also:
        FileRW.readIntsFromFile(String, boolean, boolean, int)
        Code:
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        public static final Pattern NUMBER_COMMMA_REGEX = Pattern.compile("(\\d),(\\d)");

      • NEWLINEP

        public static final java.util.regex.Pattern NEWLINEP
        This represents any version of the new-line character. Note that the '\r\n' version comes before the single '\r' version in the regular-expression, to guarantee that if both are present, they are treated as a single newline.
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        public static final Pattern NEWLINEP = Pattern.compile("\\r\\n|\\r|\\n");

      • GENERIC_PARAMS

        public static final java.util.regex.Pattern GENERIC_PARAMS
        This will match the definition for a java 'Generic' class or interface
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        public static final Pattern GENERIC_PARAMS = Pattern.compile("^.+?<([\\s\\w\\<>,\\?]+)>$");

      • PACKAGE_NAME

        public static final java.util.regex.Pattern PACKAGE_NAME
        This shall match a Java Package String
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        public static final Pattern PACKAGE_NAME = Pattern.compile("([A-Za-z_]\\w*\\.)+");

      • REG_EX_ESCAPE_CHARS

        public static final java.lang.String REG_EX_ESCAPE_CHARS
        This is the list of characters that need to be escaped for a regular expression
        See Also:
        Constant Field Values
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        public static final String REG_EX_ESCAPE_CHARS = "\\/()[]{}$^+*?-.";

      • ALPHA_NUMERIC

        public static final java.util.regex.Pattern ALPHA_NUMERIC
        Alpha-Numeric RegEx
        Code:
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        public static final Pattern ALPHA_NUMERIC = Pattern.compile("^\\d\\w$");

      • alphaNumPred

        public static final java.util.function.Predicate<java.lang.String> alphaNumPred
        Alpha-Numeric String Predicate.
        Code:
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        public static final Predicate<String> alphaNumPred = ALPHA_NUMERIC.asPredicate();

      • JS_ESCAPE_CHARS

        protected static final char[] JS_ESCAPE_CHARS
        When converting a String for a Java-Script String, these are the characters that must be escaped.
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        protected static final char[] JS_ESCAPE_CHARS = { '\\', '/', '\n', '\"' };

      • REGEX_ESCAPE_CHARS

        protected static final char[] REGEX_ESCAPE_CHARS
        These are 'control' characters (Reg Ex Code), so they must be escaped if the are to be treated as their ASCII-equivalent values.
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        protected static final char[] REGEX_ESCAPE_CHARS =
    { '\\', '/', '(', ')', '[', ']', '{', '}', '$', '^', '+', '*', '?', '-', '.' };

    • Method Detail

      • commas

        public static java.lang.String commas​(long l)
        Makes a long number like 123456789 into a number-string such as: "123,456,789". Java's package java.text.* is easy to use, and versatile, but the commands are not always so easy to remember.
        Parameters:
        l - Any long integer. Comma's will be inserted for every third power of ten
        Returns:
        After calling java's java.text.DecimalFormat class, a String representing this parameter will be returned.
        Code:
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         return formatter.format(l);

      • trimRight

        public static java.lang.String trimRight​(java.lang.String s)
        Trims any white-space Characters from the end of a String.
        Input String:Output String:
        "A Quick Brown Fox\n \t""A Quick Brown Fox"
        "\tA Lazy Dog.""\tA Lazy Dog."
        " " (only white-space)""
        "" (empty-string)""
        nullthrows NullPointerException
        Parameters:
        s - Any Java String
        Returns:
        A copy of the same String - but all characters that matched Java method java.lang.Character.isWhitespace(char) and were at the end of the String will not be included in the returned String.

        If the zero-length String is passed to parameter 's', it shall be returned immediately.

        If the resultant-String has zero-length, it is returned, without exception.
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         if (s.length() == 0) return s;

 int pos = s.length();

 while ((pos > 0) && Character.isWhitespace(s.charAt(--pos)));

 if (pos == 0) if (Character.isWhitespace(s.charAt(0))) return "";

 return s.substring(0, pos + 1);

      • trimLeft

        public static java.lang.String trimLeft​(java.lang.String s)
        Trims any white-space Characters from the beginning of a String.
        Input String:Output String:
        "\t A Quick Brown Fox""A Quick Brown Fox"
        "A Lazy Dog. \n\r\t""A Lazy Dog. \n\r\t"
        " " (only white-space)""
        "" (empty-string)""
        nullthrows NullPointerException
        Parameters:
        s - Any Java String
        Returns:
        A copy of the same String - but all characters that matched Java method java.lang.Character.isWhitespace(char) and were at the start of the String will not be included in the returned String.

        If the zero-length String is passed to parameter 's', it shall be returned immediately.

        If the resultant-String has zero-length, it is returned, without exception.
        Code:
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         int pos = 0;
 int len = s.length();

 if (len == 0) return s;

 while ((pos < len) && Character.isWhitespace(s.charAt(pos++)));

 if (pos == len) if (Character.isWhitespace(s.charAt(len-1))) return "";

 return s.substring(pos - 1);

      • leftSpacePad

        public static java.lang.String leftSpacePad​(java.lang.String s,
                                            int totalStringLength)
        Primarily for convenience in remembering earlier C-style printf(...) formatting commands.

        This method will "left pad" an input String with spaces, if s.length() < totalStrLength. If input-parameter 's' is equal-to or longer-than the value in 'totalStringLength', then the original String shall be returned.
        Input ParametersReturned String
        "Quick Brown Fox"
        20        		 
        "     Quick Brown Fox"
        "Hello World"
        15        		 
        "    Hello World"
        "Write Once, Run Anywhere"
        10        		 "Write Once, Run Anywhere"
        nullNullPointerException
        Parameters:
        s - This may be any java.lang.String
        totalStringLength - If s.length() is smaller than 'totalStringLength', then as many space characters (' ') as are needed to ensure that the returned 'String' has length equal to 'totalStringLength' will be prepended to the input String parameter 's'.

        If s.length() is greater than 'totalStringLength', then the original input shall be returned.
        Throws:
        java.lang.IllegalArgumentException - If totalStringLength is zero or negative.
        See Also:
        rightSpacePad(String, int)
        Code:
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         if (totalStringLength <= 0) throw new IllegalArgumentException(
     "totalString length was '" + totalStringLength + ", " +
     "however it is expected to be a positive integer."
 );

 return (s.length() >= totalStringLength) 
     ? s 
     : String.format("%1$" + totalStringLength + "s", s);

      • rightSpacePad

        public static java.lang.String rightSpacePad​(java.lang.String s,
                                             int totalStringLength)
        Primarily for convenience in remembering earlier C-style printf(...) formatting commands.

        This method will "right pad" an input String with spaces, if s.length() < totalStrLength. If input-parameter 's' is equal-to or longer-than the value in 'totalStringLength', then the original String shall be returned.
        Input ParametersReturned String
        "Quick Brown Fox"
        20        		 
        "Quick Brown Fox     "
        "Hello World"
        15        		 
        "Hello World    "
        "Write Once, Run Anywhere"
        10        		 "Write Once, Run Anywhere"
        nullNullPointerException
        Parameters:
        s - This may be any java.lang.String
        totalStringLength - If s.length() is smaller than 'totalStringLength', then as many space characters (' ') as are needed to ensure that the returned 'String' has length equal to 'totalStringLength' will be postpended to the input String parameter 's'.

        If s.length() is greater than 'totalStringLength', then the original input shall be returned.
        Throws:
        java.lang.IllegalArgumentException - If totalStringLength is zero or negative.
        See Also:
        leftSpacePad(String, int)
        Code:
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         if (totalStringLength <= 0) throw new IllegalArgumentException(
     "totalString length was '" + totalStringLength + "', " +
     "however it is expected to be a positive integer."
 );

 return (s.length() >= totalStringLength) 
     ? s 
     : String.format("%1$-" + totalStringLength + "s", s);

      • setChar

        public static java.lang.String setChar​(java.lang.String str,
                                       int i,
                                       char c)
        This sets a character in a String to a new value, and returns a result.
        Parameters:
        str - Any java String
        i - An index into the underlying character array of that String.
        c - A new character to be placed at the i'th position of this String.
        Returns:
        a new java String, with the appropriate index into the String substituted using character parameter 'c'.
        Code:
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         if ((i + 1) < str.length()) return str.substring(0, i) + c + str.substring(i + 1);
 else                        return str.substring(0, i) + c;

      • delChar

        public static java.lang.String delChar​(java.lang.String str,
                                       int i)
        This removes a character from a String, and returns a new String as a result.
        Parameters:
        str - Any Java-String.
        i - This is the index into the underlying java char-array whose character will be removed from the return String.
        Returns:
        Since Java String's are all immutable, this String that is returned is completely new, with the character that was originally at index 'i' removed.
        Code:
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         if ((i + 1) < str.length())
     return str.substring(0, i) + str.substring(i + 1);
 else
     return str.substring(0, i);

      • removeDuplicateSpaces

        public static java.lang.String removeDuplicateSpaces​(java.lang.String s)
        Returns the same String is input, but trims all spaces down to a single space. Each and every lone / independent or contiguous white-space character is reduced to a single space-character.
        Input StringOutput String
        "This   has   extra   spaces\n"
        		 "This has extra spaces "
        "This does not" "This does not"
        "\tThis\nhas\ttabs\nand\tnewlines\n" " This has tabs and newlines "
        Parameters:
        s - Any Java String
        Returns:
        A String where all white-space is compacted to a single space. This is generally how HTML works, when it is displayed in a browser.
        Code:
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         return StringParse.WHITE_SPACE_REGEX.matcher(s).replaceAll(" ");

      • removeWhiteSpace

        public static java.lang.String removeWhiteSpace​(java.lang.String s)
        This string-modify method simply removes any and all white-space matches found within a java-String.
        Input StringOutput String
        "This   Has   Extra   Spaces\n"
        		 "ThisHasExtraSpaces"
        "This Does Not" "ThisDoesNot"
        "\tThis\nHas\tTabs\nAnd\tNewlines\n" "ThisHasTabsAndNewlines"
        Parameters:
        s - Any String, but if it has any white-space (space that matches regular-expression: \w+) then those character-blocks will be removed
        Returns:
        A new String without any \w (RegEx for 'whitespace')
        See Also:
        WHITE_SPACE_REGEX
        Code:
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         return WHITE_SPACE_REGEX.matcher(s).replaceAll("");

      • lineOrLines

        public static java.lang.String lineOrLines​(java.lang.String s,
                                           int pos,
                                           int len,
                                           java.lang.String unixColorCode)
        This will return the complete text-lines of character data for the line identified by token-substring position parameters pos and len. This method will search, in the left-direction (decreasing String index) for the first new-line character identified. It will also search, starting at position pos + len, for the first new-line character in the right-direction (increasing String index).

        If the token-substring identified by s.substring(pos, len) itself contains any new-line characters, these will neither affect the prepended, nor the post-pended search String. To be precise, any newline characters between 'pos' and 'len' will be irrelevant to the left-wards and right-wards newlines searches for new-line characters.
        Parameters:
        s - This may be any valid Java String. It ought to be some variant of a text-file. It will be searched for the nearest '\n' character - in both directions, left and right - from parameter int 'pos' and parameter int 'len'
        pos - This is a position in the input-parameter String 's'. The nearest '\n' (new-line) character, to the left of this position, will be found and identified. If the char at s.charAt(pos) is, itself, a '\n' (newline) character, then no left-direction search will be performed. The left-most position of the returned substring would then be pos + 1.
        len - The search for the 'right-most' '\n' (newline-character) will begin at position 'len'. If the character at s.charAt(pos + len) is, itself, a new-line character, then no right-direction search will be performed. The right-most position of the returned substring would be pos + len - 1.
        unixColorCode - If this String is null, it will be ignored. If this String is non-null, it will be inserted before the "Matching String" indicated by the index-boundaries pos TO pos + len.

        NOTE: No Validity Check shall be performed on this String, and the user is not obligated to provide a Shell.C valid UNIX Color-Code String. Also, a closing C.RESET is inserted after the terminus of the match.
        Returns:
        The String demarcated by the first new-line character PLUS 1 BEFORE index 'pos', and the first new-line character MINUS 1 AFTER index pos + len.

        NOTE: The above does mean, indeed, that the starting and ending new-lines WILL NOT be included in the returned String.

        ALSO: Also, if there are no new-line characters before position 'pos', then every character beginning at position zero will be included in the returned String result. Also, if there are no new-line characters after position pos + len then every character after position pos + len will be appended to the returned String result.
        Throws:
        java.lang.StringIndexOutOfBoundsException - If either 'pos', or 'pos + len' are not within the bounds of the input String 's'
        java.lang.IllegalArgumentException - If the value passed to parameter 'len' is zero or negative.
        Code:
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         if ((pos >= s.length()) || (pos < 0)) throw new StringIndexOutOfBoundsException(
     "The integer passed to parameter 'pos' [" + pos + "], is past the bounds of the end " +
     "of String 's', which has length [" + s.length() + "]"
 );

 if (len <= 0) throw new IllegalArgumentException
     ("The value passed to parameter 'len' [" + len + "], may not be negative.");

 if ((pos + len) > s.length()) throw new StringIndexOutOfBoundsException(
     "The total of parameter 'pos' [" + pos + "], and parameter 'len' [" + len + "], is: " +
     "[" + (pos + len) + "].  Unfortunately, String parameter 's' only has length " +
     "[" + s.length() + "]"
 );

 int linesStart, linesEnd, temp;

 if (pos == 0)                                           linesStart  = 0;
 else if (s.charAt(pos) == '\n')                         linesStart  = pos + 1; 
 else if ((temp = StrIndexOf.left(s, pos, '\n')) != -1)  linesStart  = temp + 1;
 else                                                    linesStart  = 0;

 if ((pos + len) == s.length())                          linesEnd    = s.length();
 else if (s.charAt(pos + len) == '\n')                   linesEnd    = pos + len;
 else if ((temp = s.indexOf('\n', pos + len)) != -1)     linesEnd    = temp;
 else                                                    linesEnd    = s.length();

 /*
 // VERY USEFUL FOR DEBUGGING.  DO NOT DELETE...
 // NOTE: This method is the one that GREP uses.
 System.out.println("s.charAt(pos)\t\t= "    + "[" + s.charAt(pos) + "]");
 System.out.println("s.charAt(pos+len)\t= "  + "[" + s.charAt(pos+len) + "]");
 System.out.println("s.length()\t\t= "       + s.length());
 System.out.println("pos\t\t\t= "            + pos);
 System.out.println("pos + len\t\t= "        + (pos + len));
 System.out.println("linesStart\t\t= "       + linesStart);
 System.out.println("linesEnd\t\t= "         + linesEnd);
 */

 return  (unixColorCode != null)
     ?   s.substring(linesStart, pos) + 
         unixColorCode + s.substring(pos, pos + len) + C.RESET + 
         s.substring(pos + len, linesEnd)
     :   s.substring(linesStart, pos) + 
         s.substring(pos, pos + len) + 
         s.substring(pos + len, linesEnd);

      • line

        public static java.lang.String line​(java.lang.String s,
                                    int pos)
        This will return the complete text-line of character data from 'inside' the input-parameter String s. The meaning of 'complete text-line', in this method, is that any and all character data between the first '\n' (new-line character) when scanning towards the right (increasing String-index) and the first '\n' character when scanning towards the left (decreasing index) constitutes 'a line' (of text-data).

        This scan shall for the left-most and right-most new-line shall begin at String-index parameter pos. If either the left-direction or right-direction scan does not find any new-line characters, then start and end indices of the returned line of text shall be demarcated by input-String index '0' and index String.length(), respectively
        Parameters:
        s - This may be any valid Java String. It ought to be some variant of a text-file. It will be searched for the nearest '\n' character - in both directions, left and right - from parameter int 'pos'.
        pos - This is a position in the input-parameter String 's'. The nearest new-line character both to the left of this position, and to the right, will be found and identified. If the character at s.charAt(pos) is itself a newline '\n' character, then an exception shall throw.
        Returns:
        The String identified by the first new-line character PLUS 1 BEFORE index 'pos', and the first new-line character MINUS 1 AFTER index 'pos + len'.

        NOTE: The above means, that the starting and ending new-lines, themselves, will not be included in the String that is returned.

        ALSO: Also, if there are no new-line characters before position 'pos', then every character beginning at position zero will be included in the returned String result. Also, if there are no new-line characters after position 'pos + len' then every character after position 'pos + len' will be appended to the returned String result.
        Throws:
        java.lang.StringIndexOutOfBoundsException - If is not within the bounds of the input String 's'
        java.lang.IllegalArgumentException - If the character in String 's' at position 'pos' is a newline '\n', itself.
        Code:
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         if ((pos > s.length()) || (pos < 0)) throw new StringIndexOutOfBoundsException(
     "The integer passed to parameter 'pos' [" + pos + "], is past the bounds of the end of " +
     "String 's', which has length [" + s.length() + "]"
 );

 if (s.charAt(pos) == '\n') throw  new IllegalArgumentException(
     "The position-index for string-parameter 's' contains, itself, a new line character " +
     "'\\n.'  This is not allowed here."
 );

 int lineStart   = StrIndexOf.left(s, pos, '\n');
 int lineEnd     = s.indexOf('\n', pos);

 if (lineStart == -1)    lineStart   = 0;
 if (lineEnd == -1)      lineEnd     = s.length();

 return  s.substring(lineStart + 1, lineEnd);

      • hasWhiteSpace

        public static boolean hasWhiteSpace​(java.lang.String s)
        This method checks whether or not a java-String has white-space.
        Parameters:
        s - Any Java-String. If this String has any white-space, this method will return TRUE
        Returns:
        TRUE If there is any white-space in this method, and FALSE otherwise.
        See Also:
        WHITE_SPACE_REGEX
        Code:
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         return WHITE_SPACE_REGEX.matcher(s).find();

      • countCharacters

        public static int countCharacters​(java.lang.String s,
                                  char c)
        Counts the number of instances of character input char c contained by the input String s
        Parameters:
        s - Any String containing any combination of ASCII/UniCode characters
        c - Any ASCII/UniCode character.
        Returns:
        The number of times char c occurs in String s
        Code:
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         int count = 0;
 int pos   = 0;
 while ((pos = s.indexOf(c, pos + 1)) != -1) count++;
 return count;

      • ifQuotesStripQuotes

        public static java.lang.String ifQuotesStripQuotes​(java.lang.String s)
        If the String passed to this method contains a single-quote on both sides of the String, or if it contains a double-quote on both sides of this String, then this method shall return a new String that is shorter in length by 2, and leaves off the first and last characters of the input parameter String.

        HOPEFULLY, The name of this method explains clearly what this method does
        Parameters:
        s - This may be any java String. Only String's whose first and last characters are not only quotation marks (single or double), but also they are the same, identical, quotation marks on each side.
        Returns:
        A new String that whose first and last quotation marks are gone - if they were there when this method began.
        Code:
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         if (s == null)      return null;
 if (s.length() < 2) return s;

 int lenM1 = s.length() - 1; // Position of the last character in the String

 if (    ((s.charAt(0) == '\"')  && (s.charAt(lenM1) == '\"'))       // String has Double-Quotation-Marks
                                 ||                                  //            ** or ***
         ((s.charAt(0) == '\'')  && (s.charAt(lenM1) == '\''))  )    // String has Single-Quotation-Marks
     return s.substring(1, lenM1);
 else  
     return s;

      • monthStr

        public static java.lang.String monthStr​(int month)
        Converts an integer into a Month. I could just use the class java.util.Calendar, but it is so complicated, that using an internal array is easier.

        String months[] = { month names };
        Parameters:
        month - The month, as a number from '1' to '12'.
        Returns:
        A month as a String like: "January" or "August"
        Code:
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         return months[month-1];

      • dateStr

        public static java.lang.String dateStr()
        Generates a "Date String" using the character separator '.'
        Returns:
        A String in the form: YYYY.MM.DD
        Code:
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         return dateStr('.', false);

      • dateStr

        public static java.lang.String dateStr​(char separator)
        Generates a "Date String" using the separator parameter as the separator between numbers
        Parameters:
        separator - Any ASCII or UniCode character.
        Returns:
        A String of the form: YYYYcMMcDD where 'c' is the passed 'separator' parameter.
        Code:
        Exact Method Body:
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         return dateStr(separator, false);

      • dateStrGOVCN

        public static java.lang.String dateStrGOVCN()
        Generates a "Date String" that is consistent with the directory-name file-storage locations used to store articles from http://Gov.CN.
        Returns:
        The String's used for the Chinese Government Web-Portal Translation Pages
        Code:
        Exact Method Body:
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         return dateStr('/', false).replaceFirst("/", "-");

      • dateStr

        public static java.lang.String dateStr​(char separator,
                                       boolean includeMonthName)
        This class is primary included because although Java has a pretty reasonable "general purpose" calendar class/interface, but a consistent / same String since is needed because the primary use here is for building the names of files.
        Parameters:
        separator - Any ASCII or Uni-Code character.
        includeMonthName - When TRUE, the English-Name of the month ('January' ... 'December') will be appended to the month number in the returned String.
        Returns:
        The year, month, and day as a String.
        Code:
        Exact Method Body:
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         Calendar    c   = internalCalendar;
 String      m   = zeroPad10e2(c.get(Calendar.MONTH) + 1); // January is month zero!
 String      d   = zeroPad10e2(c.get(Calendar.DAY_OF_MONTH));

 if (includeMonthName) m += " - " + c.getDisplayName(Calendar.MONTH, 2, Locale.US);

 if (separator != 0) return c.get(Calendar.YEAR) + "" + separator + m + separator + d;
 else                return c.get(Calendar.YEAR) + "" + m + d;

      • ymDateStr

        public static java.lang.String ymDateStr()
        Returns a String that has the year and the month (but not the day, or other time components).
        Returns:
        Returns the current year and month as a String.
        Code:
        Exact Method Body:
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         return ymDateStr('.', false);

      • ymDateStr

        public static java.lang.String ymDateStr​(char separator)
        Returns a String that has the year and the month (but not the day, or other time components).
        Parameters:
        separator - The single-character separator used between year, month and day.
        Returns:
        The current year and month as a String.
        Code:
        Exact Method Body:
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         return ymDateStr(separator, false);

      • ymDateStr

        public static java.lang.String ymDateStr​(char separator,
                                         boolean includeMonthName)
        Returns a String that has the year and the month (but not the day, or other time components).
        Parameters:
        separator - The single-character separator used between year, month and day.
        includeMonthName - When this is true, the name of the month, in English, is included with the return String.
        Returns:
        YYYYseparatorMM(? include-month-name)
        Code:
        Exact Method Body:
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         Calendar    c   = internalCalendar;
 String      m   = zeroPad10e2(c.get(Calendar.MONTH) + 1); // January is month zero!

 if (includeMonthName) m += " - " + c.getDisplayName(Calendar.MONTH, 2, Locale.US);

 if (separator != 0) return c.get(Calendar.YEAR) + "" + separator + m;
 else                return c.get(Calendar.YEAR) + "" + m;

      • timeStr

        public static java.lang.String timeStr()
        Returns the current time as a String.
        Returns:
        military time - with AM|PM (redundant) added too. Includes only Hour and Minute - separated by a colon character ':'
        See Also:
        timeStr(char)
        Code:
        Exact Method Body:
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         return timeStr(':');

      • timeStr

        public static java.lang.String timeStr​(char separator)
        Returns the current time as a String.
        Parameters:
        separator - The character used to separate the minute & hour fields
        Returns:
        military time - with AM|PM added redundantly, and a separator of your choosing.
        Code:
        Exact Method Body:
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         Calendar    c   = internalCalendar;
 int         ht  = c.get(Calendar.HOUR) + ((c.get(Calendar.AM_PM) == Calendar.AM) ? 0 : 12);
 String      h   = zeroPad10e2((ht == 0) ? 12 : ht);  // 12:00 is represented as "0"... changes this...
 String      m   = zeroPad10e2(c.get(Calendar.MINUTE));
 String      p   = (c.get(Calendar.AM_PM) == Calendar.AM) ? "AM" : "PM";

 if (separator != 0) return h + separator + m + separator + p;
 else                return h + m + p;

      • timeStrComplete

        public static java.lang.String timeStrComplete()
        Returns the current time as a String. This method uses all time components available.
        Returns:
        military time - with AM|PM added redundantly.
        Code:
        Exact Method Body:
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         Calendar    c   = internalCalendar;
 int         ht  = c.get(Calendar.HOUR) + ((c.get(Calendar.AM_PM) == Calendar.AM) ? 0 : 12);
 String      h   = zeroPad10e2((ht == 0) ? 12 : ht);  // 12:00 is represented as "0"... changes this...
 String      m   = zeroPad10e2(c.get(Calendar.MINUTE));
 String      s   = zeroPad10e2(c.get(Calendar.SECOND));
 String      ms  = zeroPad(c.get(Calendar.MILLISECOND));
 String      p   = (c.get(Calendar.AM_PM) == Calendar.AM) ? "AM" : "PM";

 return h + '-' + m + '-' + p + '-' + s + '-' + ms + "ms";

      • ordinalIndicator

        public static java.lang.String ordinalIndicator​(int i)
        The words "ordinal indicator" are referring to the little character String that is often used in English to make a number seem more a part of an english sentence.
        Parameters:
        i - Any positive integer (greater than 0)
        Returns:
        This will return the following strings:
        Input: RETURNS:
        i = 1 "st"  (as in "1st","first")
        i = 2 "nd"  (as in "2nd", "second")
        i = 4 "th"  (as in "4th")
        i = 23 "rd"  (as in "23rd")
        Throws:
        java.lang.IllegalArgumentException - If i is negative, or zero
        Code:
        Exact Method Body:
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         if (i < 1) throw new IllegalArgumentException("i: " + i + "\tshould be a natural number > 0.");

 // Returns the last 2 digits of the number, or the number itself if it is less than 100.
 // Any number greater than 100 - will not have the "text-ending" (1st, 2nd, 3rd...) affected -
 // by the digits after the first two digits.  Just analyze the two least-significant digits.
 i = i % 100;

 // All numbers between "4th" and "19th" end with "th"
 if ((i > 3) && (i < 20))    return "th";

 // set i to be the least-significant digit of the number - if that number was 1, 2, or 3
 i = i % 10;

 // Obvious: English Rules.
 if (i == 1)                 return "st";
 if (i == 2)                 return "nd";
 if (i == 3)                 return "rd";

 // Compiler is complaining.  This statement should never be executed.
 return "th";

      • zeroPad

        public static java.lang.String zeroPad​(int n)
        This just zero-pads integers with "prepended" zero's. java.text has all kinds of extremely intricate zero-padding and text-formatting classes. However, here, these are generally used for debug, line-number, or count information that is printed to the UNIX terminal. When this is the case, a simple and easily remembered 'one line method' is a lot more useful than all of the highly-scalable versions of the text-formatting classes in java.text.
        Parameters:
        n - Any Integer. If 'n' is negative or greater than 1,000 - then null is returned.
        Returns:
        A zero-padded String - to precisely three orders of 10, as in the example table below:
        Input RETURNS:
        n = 9 "009"
        n = 99 "099"
        n = 999 "999"
        n = 9999 null
        n = -10 null
        See Also:
        zeroPad10e2(int), zeroPad10e4(int)
        Code:
        Exact Method Body:
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         if (n < 0)      return null;
 if (n < 10)     return "00" + n;
 if (n < 100)    return "0" + n;
 if (n < 1000)   return "" + n;
 return null;

      • zeroPad10e2

        public static java.lang.String zeroPad10e2​(int n)
        Pads an integer such that it contains enough leading zero's to ensure a String-length of two.
        Parameters:
        n - Must be an integer between 0 and 99, or else null will be returned
        Returns:
        A zero-padded String of the integer, to precisely two orders of 10
        . Null is returned if the number cannot fit within two spaces. Example table follows:
        Input RETURNS:
        n = 9 "09"
        n = 99 "99"
        n = 999 null
        n = -10 null
        See Also:
        zeroPad(int)
        Code:
        Exact Method Body:
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         if (n < 0)      return null;
 if (n < 10)     return "0" + n;
 if (n < 100)    return "" + n;
 return null;

      • zeroPad10e4

        public static java.lang.String zeroPad10e4​(int n)
        Pads an integer such that it contains enough leading zero's to ensure a String-length of four.
        Parameters:
        n - Must be an integer between 0 and 9999, or else null will be returned
        Returns:
        A zero-padded String of the integer, to precisely four orders of 10. Null is returned if the number cannot fit within four spaces. Example table follows:
        Input RETURNS:
        n = 9 "0009"
        n = 99 "0099"
        n = 999 "0999"
        n = 9999 "9999"
        n = 99999 null
        n = -10 null
        See Also:
        zeroPad(int)
        Code:
        Exact Method Body:
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         if (n < 0)      return null;
 if (n < 10)     return "000" + n;
 if (n < 100)    return "00" + n;
 if (n < 1000)   return "0" + n;
 if (n < 10000)  return "" + n;
 return null;

      • zeroPad

        public static java.lang.String zeroPad​(int n,
                                       int powerOf10)
        Pad's an integer with leading zeroes into a String. The number of zeroes padded is equal to parameter 'powerOf10'. If int 'powerOf10' were equal to zero, then any integer passed to this function would return a String that was precisely three characters long. If the value of parameter int 'n' were larger than 1,000 or negative, then null would be returned.
        Parameters:
        n - Must be an integer between '0' and '9999' where the number of '9' digits is equal to the value of parameter int 'powerOf10'
        powerOf10 - This must be a positive integer greater than '1'. It may not be larger '11'. The largest value that any integer in Java may attain is '2,147,483, 647'
        Returns:
        A zero padded String. If a negative number is passed to parameter 'n', then 'null' shall be returned. Null shall also be returned if the "Power of 10 Exponent of parameter n" is greater than the integer-value of parameter 'powerOf10'

        FOR INSTANCE: a call to: zeroPad(54321, 4); would return null since the value of parameter 'n' has five-decimal-places, but 'powerOf10' is only 4!
        Throws:
        java.lang.IllegalArgumentException - if the value parameter 'powerOf10' is less than 2, or greater than 11.
        Code:
        Exact Method Body:
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         if (n < 0) return null;                 // Negative Values of 'n' not allowed

 char[]  cArr    = new char[powerOf10];  // The String's length will be equal to 'powerOf10'
 String  s       = "" + n;               //       (or else 'null' would be returned)
 int     i       = powerOf10 - 1;        // Internal Loop variable
 int     j       = s.length() - 1;       // Internal Loop variable

 Arrays.fill(cArr, '0');                 // Initially, fill the output char-array with all zeros

 while ((i >= 0) && (j >= 0))            // Now start filling that char array with the actual number
     cArr[i--] = s.charAt(j--);

 if (j >= 0) return null;                // if all of parameter 'n' was inserted into the output
                                         // (number 'n' didn't fit) then powerOf10 was insufficient,
                                         // so return null.

 return new String(cArr);

      • grep_HREF_tag

        public static java.lang.String grep_HREF_tag​(java.lang.String s)
        If parameter String s contains any tag within-which there is a valid "HREF", this will return the contents of the HREF Attribute/InnerTag.
        Parameters:
        s - This is usually some variant of an HTML element/tag String. This method was the first one written for HTML in this scrape package, and is just kept here for legacy reasons. The class HTML.TagNode has a number of options for extracting the 'HREF' attribute from an HTML element.
        Returns:
        The attribute-value of an HREF=... attribute inside (usually an <A> 'Anchor') HTML tag. This will return 'null' if there is no HREF="..." attribute-value pair is found or identified.
        Throws:
        java.lang.IllegalArgumentException - If there is no end-quote found for the HREF="..." sub-string.
        Code:
        Exact Method Body:
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         s = s.toLowerCase();
 String quote = "\"";

 int hrefPos = s.indexOf("href=\"");
 if (hrefPos == -1)
 {
     hrefPos = s.indexOf("href='");
     if (hrefPos == -1) return null;
     quote = "'";
 }
 // System.out.print("\t[hrefPos=" + hrefPos + "]");
        
 // the " + 6" is because the string HREF=" is 6 characters long
 String ret = s.substring(hrefPos + 6);
 int endQuotePos = ret.indexOf(quote);
        
 if (endQuotePos == -1) throw new IllegalArgumentException("HREF has no EndQuote!\n\nFor String:\n" + s);
 // System.out.print("endQuotePos = " + endQuotePos + " " + ret.substring(0, endQuotePos));
 return ret.substring(0,endQuotePos);

      • grep_IMG_SRC_tag

        public static java.lang.String grep_IMG_SRC_tag​(java.lang.String s)
        If parameter String s contains an HTML "IMG" tag, this will return the contents of the "SRC=..." attribute tag-field.
        Parameters:
        s - This is usually some variant of an HTML element/tag String. This method was the first one written for HTML in this scrape package, and is just kept here for legacy reasons. The class HTML.TagNode has a number of options for extracting the 'SRC' attribute from an HTML element.
        Returns:
        The attribute-value of a SRC=... attribute inside (usually an <IMG> 'Image') HTML tag. 'null' is returned if:

        1. There is no HTML 'IMG' token found in the String
        2. There is no SRC='...' attribute-value pair found.
        Code:
        Exact Method Body:
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         String stlc = s.toLowerCase();
 // System.out.println("1: " + stlc);
        
 int imgPos = stlc.indexOf("<img ");

 if (imgPos == -1) return null;
 stlc = stlc.substring(imgPos + 5);
 // System.out.println("2: " + stlc + "[imgPos=" + imgPos + "]");

 // first check for double-quotes
 String quote = "\"";
 int srcPos = stlc.indexOf("src=\"");
 if (srcPos == -1)
 {
     // if no double-quotes, try single quotes
     srcPos = stlc.indexOf("src='");
     if (srcPos == -1) return null;
     quote = "'";
 }
 stlc = stlc.substring(srcPos + 5);
 // System.out.println("3: " + stlc + "[srcPos=" + srcPos + "]");
        
 int endSrcPos = stlc.indexOf(quote);
 if (endSrcPos == -1) return null;
        
 int urlStart    = imgPos + srcPos + 10;
 int urlEnd      = urlStart + endSrcPos;
        
 // System.out.println("4: [endSrcPos=" + endSrcPos + ", urlStart=" + urlStart + ", urlEnd=" + urlEnd);
 return s.substring(urlStart, urlEnd);

      • findLastFrontSlashPos

        public static int findLastFrontSlashPos​(java.lang.String urlOrDir)
        This function finds the position of the last "front-slash" character '/' in a java-String
        Parameters:
        urlOrDir - This is any java-String, but preferably one that is a URL, or directory.
        Returns:
        The String-index of the last 'front-slash' '/' position in a String, or -1 if there are not front-slashes.
        Code:
        Exact Method Body:
        1
         return urlOrDir.lastIndexOf('/');

      • fromLastFrontSlashPos

        public static java.lang.String fromLastFrontSlashPos​
            (java.lang.String urlOrDir)
        This returns the contents of a String, after the last front-slash found.

        NOTE: If not front-slash '/' character is found, then the original String is returned.
        Parameters:
        urlOrDir - This is any java-String, but preferably one that is a URL, or directory.
        Returns:
        the portion of the String after the final front-slash '/' character. If there are no front-slash characters found in this String, then the original String shall be returned.
        Code:
        Exact Method Body:
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         int pos = urlOrDir.lastIndexOf('/');
 if (pos == -1) return urlOrDir;
 return urlOrDir.substring(pos + 1);

      • beforeLastFrontSlashPos

        public static java.lang.String beforeLastFrontSlashPos​
            (java.lang.String urlOrDir)
        This returns the contents of a String, before the last front-slash found (including the front-slash '/' itself).

        NOTE: If no front-slash '/' character is found, then null is returned.
        Parameters:
        urlOrDir - This is any java-String, but preferably one that is a URL, or directory.
        Returns:
        the portion of the String before and including the final front-slash '/' character. If there are no front-slash characters found in this String, then null.
        Code:
        Exact Method Body:
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         int pos = urlOrDir.lastIndexOf('/');
 if (pos == -1) return null;
 return urlOrDir.substring(0, pos + 1);

      • findLastFileSeparatorPos

        public static int findLastFileSeparatorPos​(java.lang.String fileOrDir)
        This function finds the position of the last 'java.io.File.separator' character in a java-String. In UNIX-based systems, this is a forward-slash '/' character, but in Windows-MSDOS, this is a back-slash '\' character. Identifying which of the two is used is obtained by "using" Java's File.separator class and field.
        Parameters:
        fileOrDir - This may be any Java-String, but preferably one that represents a file or directory.
        Returns:
        The String-index of the last 'file-separator' position in a String, or -1 if there are no such file-separators.
        Code:
        Exact Method Body:
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         return fileOrDir.lastIndexOf(File.separator.charAt(0));

      • fromLastFileSeparatorPos

        public static java.lang.String fromLastFileSeparatorPos​
            (java.lang.String fileOrDir)
        This returns the contents of a String, after the last 'java.io.File.separator' found.

        NOTE: If no 'java.io.File.separator' character is found, then the original String is returned.
        Parameters:
        fileOrDir - This is any java-String, but preferably one that is a filename or directory-name
        Returns:
        the portion of the String after the final 'java.io.File.separator' character. If there are no such characters found, then the original String shall be returned.
        Code:
        Exact Method Body:
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         int pos = fileOrDir.lastIndexOf(File.separator.charAt(0));
 if (pos == -1) return fileOrDir;
 return fileOrDir.substring(pos + 1);

      • beforeLastFileSeparatorPos

        public static java.lang.String beforeLastFileSeparatorPos​
            (java.lang.String urlOrDir)
        This returns the contents of a String, before the last 'java.io.File.separator' (including the separator itself).

        NOTE: If no 'java.io.File.separator' character is found, then null is returned.
        Parameters:
        urlOrDir - This is any java-String, but preferably one that is a URL, or directory.
        Returns:
        the portion of the String before and including the final 'java.io.File.separator' character. If there are no such characters found in this String, then null is returned.
        Code:
        Exact Method Body:
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         int pos = urlOrDir.lastIndexOf(File.separator.charAt(0));
 if (pos == -1) return null;
 return urlOrDir.substring(0, pos + 1);

      • findExtension

        public static int findExtension​(java.lang.String file,
                                boolean includeDot)
        This will return the location within a String where the last period ('.') is found.

        ALSO: No validity checks for valid file-system names are performed. Rather, the portion of the input-String starting at the location of the last period is returned, regardless of what the String contains.
        Parameters:
        file - This may be any Java-String, but preferably one that represents a file.
        includeDot - When this parameter is passed TRUE, the position-index that is returned will be the location of the last index where a period ('.') is found. When FALSE, the index returned will be the location of that period + 1.
        Returns:
        This will return the location of the file-extension. If no period is found, then -1 is returned. If the period is the last char in the String, and parameter 'includeDot' is FALSE, then -1 is returned.
        Code:
        Exact Method Body:
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         int pos = file.lastIndexOf('.');
 if (pos == -1) return -1;
 if (includeDot) return pos;
 pos++;
 return (pos < file.length()) ? pos : -1;

      • fromExtension

        public static java.lang.String fromExtension​(java.lang.String file,
                                             boolean includeDot)
        This returns the contents of a String, after the last period '.' in that String. For file-system and web files, this is often referred to as the file extension.

        NOTE: If no period '.' character is found, then null is returned.

        ALSO: No validity checks for valid file-system names are performed. Rather, the portion of the input-String starting at the location of the last period is returned, regardless of what the String contains.
        Parameters:
        file - This is any java-String, but preferably one that is a filename.
        includeDot - This determines whether the period '.' is to be included in the returned-String.
        Returns:
        the portion of the String after the final period '.' character. If parameter includeDot has been passed FALSE, then the portion of the input-String beginning after the last period is returned.

        If there are no period characters found in this String, then null is returned.
        Code:
        Exact Method Body:
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         int pos = findExtension(file, includeDot);
 if (pos == -1) return null;
 return file.substring(pos);

      • beforeExtension

        public static java.lang.String beforeExtension​(java.lang.String file)
        This returns the contents of a String, before the last period '.' in that String. For file-system and web files, this is often referred to as the file extension.

        NOTE: If no period '.' character is found, then the original String is returned.

        ALSO: No validity checks for valid file-system names are performed. Rather, the portion of the input-String starting at the location of the last period is returned, regardless of what the String contains.
        Parameters:
        file - This is any java-String, but preferably one that is a filename.
        Returns:
        the portion of the String before the final period '.' character.

        If there are no period characters found in this String, then the original file is returned.
        Code:
        Exact Method Body:
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         int pos = file.lastIndexOf('.');
 if (pos == -1) return file;
 return file.substring(0, pos);

      • findURLRoot

        public static java.lang.String findURLRoot​(java.lang.String url)
        This function returns the root URL-directory of a String

        SPECIFICALLY: it searches for the "last forward slash" in a String, and returns a substring from position 0 to that point. If there aren't any forward slashes in this String, null is returned. The front-slash itself is included in the returned String.

        NOTE: It is similar to the old MS-DOS call to "DIR PART"
        Parameters:
        url - Any String that is intended to be an "Internet URL" - usually http://domain/directory/[file]
        Returns:
        substring(0, index of last front-slash ('/') in String)
        Code:
        Exact Method Body:
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         int pos = findLastFrontSlashPos(url);
 if (pos == -1)  return null;
 else            return url.substring(0, pos + 1);

      • firstWord

        public static java.lang.String firstWord​(java.lang.String s)
        Returns:
        After breaking the String by white-space, this returns the first 'chunk' before the first whitespace.
        Code:
        Exact Method Body:
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         int pos = s.indexOf(" ");
 if (pos == -1)  return s;
 else            return s.substring(0, pos);

      • removeBrackets

        public static java.lang.String removeBrackets​(java.lang.String s)
        This function will remove any pairs of Brackets within a String, and returned the paired down String
        Parameters:
        s - Any String, which may or may not contain a "Bracket Pair"

        For Example:

        • This String does contain [a pair of brackets] within!
        • But this String does not.
        Returns:
        The same String, but with any bracket-pairs removed.
        Code:
        Exact Method Body:
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         return remove_(s, '[', ']');

      • removeBraces

        public static java.lang.String removeBraces​(java.lang.String s)
        Functions the same as removeBrackets(String) - but removes pairs of curly-braces, instead
        NOTE:These are { curly braces } that will be removed by this String!
        Parameters:
        s - Any valid String { such as } - (even this String).

        For Example:

        • This String does contain {a pair of curly-braces} within!
        • But this String does not.
        Returns:
        The same String, but with any curly-brace-pairs removed.
        See Also:
        removeBrackets(String)
        Code:
        Exact Method Body:
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         return remove_(s, '{', '}');

      • removeParens

        public static java.lang.String removeParens​(java.lang.String s)
        Removes Parenthesis, similar to other parenthetical removing functions.
        Parameters:
        s - Any (valid) String. Below are sample inputs:

        • This String does contain (a pair of parenthesis) within!
        • But this String does not.
        Returns:
        The same String, but with any parenthesis removed.
        See Also:
        removeBrackets(String)
        Code:
        Exact Method Body:
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         return remove_(s, '(', ')');

      • removeAllParenthetical

        public static java.lang.String removeAllParenthetical​(java.lang.String s)
        Removes all parenthetical notations. Calls all remove functions
        Parameters:
        s - Any valid string
        Returns:
        The same string, but with all parenthesis, curly-brace & bracket pairs removed.
        See Also:
        removeParens(String), removeBraces(String), removeBrackets(String)
        Code:
        Exact Method Body:
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         return removeParens(removeBraces(removeBrackets(s)));

      • escStrForJavaScript

        public static java.lang.String escStrForJavaScript​(java.lang.String str)

        Copied from Stackoverflow.com - and all the "BRILLIANT ENGINEERS"!
        Really, I wish I had a reputation!!! So awful...



        Question: String.replaceAll single backslahes with double backslashes

        I'm trying to convert the String \something\ into the String \\something\\ using replaceAll, but I keep getting all kinds of errors. I thought this was the solution:

        theString.replaceAll("\\", "\\\\");

        But this gives the below exception:

        java.util.regex.PatternSyntaxException: Unexpected internal error near index 1



        The String#replaceAll() interprets the argument as a regular expression. The \ is an escape character in both String and regex. You need to double-escape it for regex:

        string.replaceAll("\\\\", "\\\\\\\\");
        But you don't necessarily need regex for this, simply because you want an exact character-by-character replacement and you don't need patterns here. So String#replace() should suffice:

        string.replace("\\", "\\\\");

        Update: as per the comments, you appear to want to use the string in JavaScript context. You'd perhaps better use StringEscapeUtils#escapeEcmaScript() instead to cover more characters
        Parameters:
        str - This may be any String in java. It is intended to be inserted into a Java-Script file between an open and close quotation marks.
        Returns:
        The String that is returned will have certain characters escaped, so that it may be wrapped in quotation marks and easily inserted into any java-script ".js" text-file.

        Escaped-Text:

        • char '\' will be escaped to: "\\"
        • char '/' will be escaped to: "\/", this is required in Java-Script, but not Java!
        • char '"' will be escaped to: "\""
        • char '\n' will be escaped to: "\\n"

        IMPORTANT NOTE: There is no easy, nor clear, way to express what is being replaced and/or escaped in a simple list. You may run this method on any String and view for yourself what changes. The primary goal of the method is to allow *any* Java String of *any* length to be converted, wrapped inside of an open and closed quotation-marks, and printed into a Java-Script ".js" file. Escaping "escape characters" which does come up some-what often in HTML text/string processing is near-impossible to explain clearly! Review the stack-overflow "incantation" for possible help.
        Code:
        Exact Method Body:
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         return StrReplace.r(str, JS_ESCAPE_CHARS, '\\');

      • escStrForRegEx

        public static java.lang.String escStrForRegEx​(java.lang.String str)
        This method should only be used for a precise String match using a regular-expression. This method shall 'escape' all characters that the JVM Regular Expression Matcher in package java.util.regex.* would expect be escaped. If the input parameter 'str' contains any regular-expression code, then this method would FAIL as it would escape regular-expression code into unusable text.
        Parameters:
        str - This should be any String for which the user would like to find an exact match, as-is.
        Returns:
        A regular-expression ready String
        Code:
        Exact Method Body:
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         return StrReplace.r(str, REGEX_ESCAPE_CHARS, '\\');

      • objToB64Str

        public static java.lang.String objToB64Str​(java.lang.Object o)
                                    throws java.io.IOException
        This will convert any Serializable Java Object into a base-64 String. This String may be saved, transmitted, even e-mailed to another party, if you wish and decoded else-where.

        REQUIREMENTS:

        1. Object must implement the interface java.io.Serializable
        2. Receiving party or storage-device must have access to the .jar file, or .class file(s) needed to instantiate that object! (You must have shared your classes if you intend to let other people de-serialize instances of that class)
        Parameters:
        o - Any java java.lang.Object. This object must be Serializable, or else the code will generate an exception.
        Returns:
        A String version of this object. It will be:

        1. Serialized using the java.io.ObjectOutputStream(...) object-serialization method
        2. Compressed using the java.io.GZIPOutputStream(...) stream-compression method
        3. Encoded to a String, via Base-64 Encoding java.util.Base64.getEncoder()

        NOTE: Compression does not always make much difference, however often times when doing web-scraping projects, there are large Java java.util.Vector<String> filled with many lines of text, and these lists may be instantly and easily saved using object-serialization. Furthermore, in these cases, the compression will sometimes reduce file-size by an order of magnitude.
        Throws:
        java.io.IOException
        See Also:
        b64StrToObj(String)
        Code:
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         ByteArrayOutputStream   bos     = new ByteArrayOutputStream();
 GZIPOutputStream        gzip    = new GZIPOutputStream(bos);
 ObjectOutputStream      oos     = new ObjectOutputStream(gzip);

 oos.writeObject(o); oos.flush(); gzip.finish(); oos.close(); bos.close();
 return Base64.getEncoder().encodeToString(bos.toByteArray());

      • b64StrToObj

        public static java.lang.Object b64StrToObj​(java.lang.String str)
                                    throws java.io.IOException
        This converts to any java.io.Serializable object from a compressed, serialized, Base-64 Encoded java.lang.String. This method can be thought of as one which converts objects which have been previously encoded as a String, and possibly even transmitted across the internet, back into an Java Object.

        REQUIREMENTS: The Object that is to be instantiated must have its class files accessible to the class-loader. This is the exact-same requirement expected by all Java "de-serializations" routines.
        Parameters:
        str - Any previously Base-64 encoded, serialized, compressed java.lang.Object' that has been saved as a String. That String should have been generated using the Programming.objToB64Str(Object o) method in this class.

        1. Serialized using the java.io.ObjectOutputStream(...) object-serialization method
        2. Compressed using the java.io.GZIPOutputStream(...) sream-compression method
        3. Encoded to a String, via Base-64 Encoding java.util.Base64.getEncoder()

        NOTE: Compression does not always make much difference, however often times when doing web-scraping projects, there are large Java java.util.Vector<String> filled with many lines of text, and these lists may be instantly and easily saved using object-serialization. Furthermore, in these cases, the compression will sometimes reduce file-size by an order of magnitude.
        Returns:
        The de-compressed java.lang.Object converted back from a String.
        Throws:
        java.io.IOException
        See Also:
        objToB64Str(Object)
        Code:
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         ByteArrayInputStream    bis     = new ByteArrayInputStream(Base64.getDecoder().decode(str));
 GZIPInputStream         gzip    = new GZIPInputStream(bis);
 ObjectInputStream       ois     = new ObjectInputStream(gzip);
 Object                  ret     = null;

 try
     { ret = ois.readObject(); }
 catch (ClassNotFoundException e)
 {
     throw new IOException(
         "There were no serialized objects found in your String.  See e.getCause();",
         e
     );
 }

 bis.close(); ois.close();
 return ret;

      • objToB64MimeStr

        public static java.lang.String objToB64MimeStr​(java.lang.Object o)
                                        throws java.io.IOException
        This performs an identical operation as the method: objToB64Str, however it generates an output String that is "MIME" compatible. All this means is that the String itself - which could conceivable by thousands or even hundreds of thousands of characters long - will have new-line characters inserted such that it may be printed on paper or included in a text-file that is (slightly) more human-readable. Base64 MIME encoded String's look like very long paragraphs of random-text data, while regular Base64-encodings are a single, very-long, String with no space characters.
        Parameters:
        o - Any java.lang.Object. This object must be Serializable, or else the code will generate an exception.
        Returns:
        A Base-64 MIME Encoded String version of any serializable java.lang.Object.
        Throws:
        java.io.IOException
        See Also:
        objToB64Str(Object), b64MimeStrToObj(String)
        Code:
        Exact Method Body:
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         ByteArrayOutputStream   bos     = new ByteArrayOutputStream();
 GZIPOutputStream        gzip    = new GZIPOutputStream(bos);
 ObjectOutputStream      oos     = new ObjectOutputStream(gzip);

 oos.writeObject(o); oos.flush(); gzip.finish(); oos.close(); bos.close();

 return Base64.getMimeEncoder().encodeToString(bos.toByteArray());

      • b64MimeStrToObj

        public static java.lang.Object b64MimeStrToObj​(java.lang.String str)
                                        throws java.io.IOException
        This performs an identical operation as the method: b64StrToObj, however receives a "MIME" compatible encoded String. All this means is that the String itself - which could conceivable by thousands or even hundreds of thousands of characters long - will have new-line characters inserted such that it may be printed on paper or included in a text-file that is (slightly) more human-readable. Base64 MIME encoded String's look like very long paragraphs of random-text data, while regular Base64 encodings a single, very-long, String's.
        Returns:
        The (de-serialized) java object that was read from the input parameter String 'str'

        REQUIREMENTS: The object that is to be instantiated must have its class files accessible to the class-loader. This is the exact-same requirement expected by all Java "de-serializations" routines.
        Throws:
        java.io.IOException
        See Also:
        b64StrToObj(String), objToB64MimeStr(Object)
        Code:
        Exact Method Body:
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         ByteArrayInputStream    bis     = new ByteArrayInputStream(Base64.getMimeDecoder().decode(str));
 GZIPInputStream         gzip    = new GZIPInputStream(bis);
 ObjectInputStream       ois     = new ObjectInputStream(gzip);
 Object                  ret     = null;

 try
     { ret = ois.readObject(); }
 catch (ClassNotFoundException e)
 { 
     throw new IOException(
         "There were no serialized objects found in your String.  See e.getCause();",
         e
     );
 }

 bis.close(); ois.close();
 return ret;

      • dotDots

        public static java.lang.String dotDots​(java.lang.String fileName,
                                       java.lang.String ancestorDirectory,
                                       char separator)
        Computes a "relative URL String".
        Parameters:
        fileName - This is a fileName whose ancestor directory needs to be 'relative-ised'
        ancestorDirectory - This is an ancestor (container) directory.
        separator - The separator character used to separate file-system directory names.
        Returns:
        This shall return the "../.." structure needed to insert a relative-URL or link into a web-page.
        Throws:
        java.lang.IllegalArgumentException - This exception shall throw if the separator character is not one of the standard file & directory separators: forward-slash '/' or back-slash '\'.

        This exception also throws if the String provided to parameter 'fileName' does not begin-with the String provided to parameter 'ancestorDirectory'.
        Code:
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         if ((separator != '/') && (separator != '\\')) throw new IllegalArgumentException(
     "The separator character provided to this method must be either a forward-slash '/' " +
     "or a back-slash ('\\') character.  You have provided: ['" + separator + "']."
 );

 if (! fileName.startsWith(ancestorDirectory)) throw new IllegalArgumentException(
     "The file-name you have provided [" + fileName + "] is a String that does " +
     "start with the ancestorDirectory String [" + ancestorDirectory + "].  " +
     "Therefore there is no relative path using the dot-dot construct to the named " +
     "ancestor directory fromm the directory where the named file resides."
 );

 int     levelsDeep  = StringParse.countCharacters(fileName, separator) - 
                       StringParse.countCharacters(ancestorDirectory, separator);

 String  dotDots     = "";

 while (levelsDeep-- > 0) dotDots = dotDots + ".." + separator;

 return dotDots;

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​(java.net.URL url)
        Convenience Method. Invokes dotDotParentDirectory(String, char, short).

        Converts URL to String, eliminates non-essential URI-information (Such as: ASP, JSP, PHP Query-Strings, and others too)

        Passes char '/', the separator character used in URL's

        Passes '1' to parameter 'nLevels' - only going up on directory.
        Code:
        Exact Method Body:
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         String urlStr = url.getProtocol() + "://" + url.getHost() + url.getPath();
 return dotDotParentDirectory(urlStr, '/', (short) 1);

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​
            (java.lang.String urlAsStr)
        Convenience Method. Invokes dotDotParentDirectory(String, char, short).

        Passes char '/', the separator character used in URL's

        Passes '1' to parameter 'nLevels' - only going up on directory.
        Code:
        Exact Method Body:
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         return dotDotParentDirectory(urlAsStr, '/', (short) 1);

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​(java.net.URL url,
                                                     short nLevels)
        Convenience Method. Invokes dotDotParentDirectory(String, char, short).

        Converts URL to String, eliminates non-essential URI-information (Such as: ASP, JSP, PHP Query-Strings, and others too)

        Passes char '/', the separator character used in URL's
        Code:
        Exact Method Body:
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         String urlStr = url.getProtocol() + "://" + url.getHost() + url.getPath();
 return dotDotParentDirectory(urlStr, '/', nLevels);

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​
            (java.lang.String urlAsStr,
             short nLevels)
        Convenience Method. Invokes dotDotParentDirectory(String, char, short).

        Passes char '/', the separator character used in URL's.
        Code:
        Exact Method Body:
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         return dotDotParentDirectory(urlAsStr, '/', nLevels);

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​
            (java.lang.String directoryStr,
             char dirSeparator)
        Convenience Method. Invokes dotDotParentDirectory(String, char, short).

        Passes '1' to parameter nLevels - only going up one directory.
        Code:
        Exact Method Body:
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         return dotDotParentDirectory(directoryStr, dirSeparator, (short) 1);

      • dotDotParentDirectory

        public static java.lang.String dotDotParentDirectory​
            (java.lang.String directoryStr,
             char separator,
             short nLevels)
        This does traverses up a directory-tree structure, and returns a 'parent-level' directory that is 'nLevels' up the tree.

        NOTE: The character used as the "File Separator" and/or "Directory Separator" can be obtained using the field: java.io.File.Separator.charAt(0). The class java.io.File provides access to the file-separator used by the file-system on which the JVM is currently running, although it treats it as a multi-character String. Just use the commonly-used java method 'charAt(0)' to obtain the forward-slash '/' or backward-slash '\' character.

        IMPORTANT: There is no error-checking performed by this method regarding whether the input String represents a valid file or directory. Instead, this method just looks for the second from last separator-character (usually a '/' forward-slash char) and returns a substring that starts at index 0, and continues to that position-plus-1 (in order to include that second-to-last separator char).
        Parameters:
        directoryStr - This may be any java-String, although it is expected to be on which represents the file & directory structure of file on the file-system. It may also be URL for a web-site
        separator - This is the separator currently used by that file & directory system. If trying to find the parent directory of a URL, this should be the forward-slash character '/'.
        nLevels - This is how many "parent-level directories" (how many levels up the tree) need to be computed. This parameter must '1' or greater. If the passed parameter 'directoryStr' does not contain enough directories to traverse up the tree, then this method will throw an IllegalArgumentException.
        Returns:
        a String that represents 'nLevels' up the directory tree, either for a directory on the local-file system, or on a web-server from a Uniform Resource Locator.
        Throws:
        java.lang.IllegalArgumentException - If the value of parameter short 'nLevels' is negative, or does not identify a number consistent with the number of directories that are contained by the input urlAsStr parameter.

        This exception shall also throw if the 'separator' character is not one of the standard file & directory separators: forward-slash '/' or back-slash '\'.
        Code:
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         if (nLevels < 1) throw new IllegalArgumentException(
     "The parameter nLevels may not be less than 1, nor negative.  You have passed: " + nLevels
 );

 if ((separator != '/') && (separator != '\\')) throw new IllegalArgumentException(
     "The separator character provided to this method must be either a forward-slash '/' " +
     "or a back-slash ('\\') character.  You have provided: ['" + separator + "']."
 );

 int count = 0;

 for (int i=directoryStr.length() - 1; i >= 0; i--)
     if (directoryStr.charAt(i) == separator)
         if (++count == (nLevels + 1))
             return directoryStr.substring(0, i + 1);

 throw new IllegalArgumentException(
     "The parameter nLevels was: " + nLevels + ", but unfortunately there only were: " + count +
     "'" + separator + "' characters found in the directory-string."
 );

      • trimEachLine

        public static java.lang.String trimEachLine​(java.lang.String str)
        This is used for "trimming each line" of an input String. Generally, when dealing with HTML there may be superfluous white-space that is useful in some places, but not necessarily when HTML is copied and pasted to other sections of a page (or to another page, altogether). This will split a String by new-line characters, and then trim each line, and afterward rebuild the String and return it.

        NOTE: This will only split the String using the standard '\n' character. If the String being used uses '\r' or '\n\r', use a different trim.
        Parameters:
        str - This may be any String. It will be split by new-line characters '\n'
        Returns:
        Returns the rebuilt String, with each line having a String.trim(); operation performed.
        Code:
        Exact Method Body:
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         StringBuilder sb = new StringBuilder();

 for (String s : str.split("\\n"))
     if ((s = s.trim()).length() == 0)   continue;
     else                                sb.append(s + '\n');

 return sb.toString().trim();

      • parseGenericType

        public static java.lang.String[] parseGenericType​
            (java.lang.String genericTypeParamOrDefinition)
        Parses a String such as T extends TreeMap<Integer, List<String>>. It is strictly used, to only parse the generic-definition lists that are at the top of generic classes and interfaces.

        Sample Input StringOutput String[] array
        "HashMap<E extends Comparable, F extends Comparable>" { "E extends Comparable", "F extends Comparable" }
        "Ret6<A, B, C, D, E, F>" { "A", "B", "C", "D", "E", "F" }
        "AbstractHNLI<?, Vector<Vector<? extends HTMLNode>>>" { "?", "Vector<Vector<? extends HTMLNode>>" }
        "VarList<Vector<HashMap<String, String>>, FileNode>" { "Vector<HashMap<String, String>>", "FileNode" }
        Parameters:
        genericTypeParamOrDefinition - This should be String retrieved from inside the less-than ('<') and greater-than ('>') symbols. For example, for SortedList<A extends Comparable, B> the String passed to this method should be "A extends Comparable, B"
        Returns:
        This should break down this CSV (comma separated value) list into individual String's.
        Throws:
        NoMatchException - if the input String parameter does not match the generics regular-expression GENERIC_PARAMS.
        StringFormatException - If the input String could not be parsed.
        Code:
        Exact Method Body:
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         Matcher                 m               = GENERIC_PARAMS.matcher(genericTypeParamOrDefinition);
 String                  innerGenericStr = m.find() ? m.group(1) : null;

 if (innerGenericStr == null) throw new NoMatchException(
     "The provided value to parameter 'genericTypeParamOrDefinition' [" + 
     genericTypeParamOrDefinition + "] did not match the Java Generics " +
     "Regular-Expression:\n" + GENERIC_PARAMS.toString()
 );

 Stream.Builder<String>  b               = Stream.builder();
 String[]                sArr            = innerGenericStr.split(",");

 for (int i=0; i < sArr.length; i++)

     // We have shifted elements, and now all of the remaining elements would be null
     // return immediately
     if (sArr[i] == null)                return b.build().toArray(String[]::new);

     // Simple generic-type definition: has no "sub-generics" or "inner-generics"
     // Add this to the list, and move on,
     else if ((! sArr[i].contains("<")) && (! sArr[i].contains(">")))
         b.accept(sArr[i].trim());

     // This is a generic-type definition that has at least one "sub-generic"
     // If there are an equal number of '<' and '>' then there were no commas
     // in between the sub-generics.  Add this to this list, and move on.
     else if (countCharacters(sArr[i], '<') == countCharacters(sArr[i], '>'))
         b.accept(sArr[i].trim());

     // There was a generic with a sub-generic that had a comma...
     else
     {
         // If we have reached the end of the String, the number of greater than and
         // less than symbols was not balanced.
         if (i == (sArr.length - 1)) throw new StringFormatException(
             "The provided value to parameter 'genericTypeParamOrDefinition' [" + 
             genericTypeParamOrDefinition + "], was not properly formatted, and could not be " +
             "parsed."
         );

         // Join the next String Array Element with the current one.
         sArr[i] = sArr[i].trim() + ", " + sArr[i + 1].trim();

         // Shift the rest of the array left.
         for (int j=i+1; j < (sArr.length-1); j++) sArr[j] = sArr[j+1];
         sArr[sArr.length - 1] = null;

         // decrement the counter to retest this array-index location
         i--;
     }

 // Return the list
 return b.build().toArray(String[]::new);

      • replaceNBSP

        public static java.lang.String replaceNBSP​(java.lang.String s)
        There are actually people out there that will insert character '160' in place of a &nbsp; element in an HTML document. How rude. Any instances of this character shall be replaced with the standard space character #32.
        Parameters:
        s - Any String will pass. Generally String's that were converted from HTML pages will contain char #160 as it is occasionally translated from the HTML escape sequence &nbsp;
        Returns:
        A String where any instance of white-space character #160 have been replaced with character #32
        Code:
        Exact Method Body:
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         return s.replace(("" + ((char) 160)), " ");

      • replaceZWSP

        public static java.lang.String replaceZWSP​(java.lang.String s)
        Even lower than #160, apparently is the "Zero Width Space" (character #8203. This is actually inserted by the JavaDoc Tool (by Sun / Oracle) into JavaDoc generated HTML Pages. Here, it shall be replaced by character #32 - the space-character.

        A.K.A.: "​".
        Parameters:
        s - Any String will pass. Generally String's that were converted from JavaDoc HTML pages will contain char #8203.
        Returns:
        A String where any instance of white-space character #8203 have been replaced with character #32
        Code:
        Exact Method Body:
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         return s.replace(("" + ((char) 8203)), " ");

      • firstNLines

        public static java.lang.String firstNLines​(java.lang.String s,
                                           int n)
        This will retrieve the first 'n' lines of a String - where a line is defined as everything up to and including the next newline '\n' character.
        Parameters:
        s - Any java String.
        n - This is the number of lines of text to retrieve.
        Returns:
        a substring of s where the last character in the String is a '\n'. The last character should be the nth '\n' character found in s. If there is no such character, then the original String shall be returned instead.
        Throws:
        NException - This exception shall throw if parameter 'n' is less than 1, or longer than s.length().
        Code:
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         NException.check(n, s);
 int pos = StrIndexOf.nth(s, n, '\n');

 if (pos != -1)  return s.substring(0, pos + 1);
 else            return s;

      • lastNLines

        public static java.lang.String lastNLines​(java.lang.String s,
                                          int n)
        This will retrieve the last 'n' lines of a String - where a line is defined as everything up to and including the next newline '\n' character.
        Parameters:
        s - Any java String.
        n - This is the number of lines of text to retrieve.
        Returns:
        a substring of 's' where the last character in the String is a new-line character '\n', and the first character is the character directly before the nth newline '\n' found in 's' - starting the count at the end of the String. If there is no such substring, then the original String shall be returned.
        Throws:
        NException - This exception shall throw if 'n' is less than 1, or longer s.length().
        Code:
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         NException.check(n, s);
 int pos = StrIndexOf.nthFromEnd(s, n, '\n');

 if (pos != -1)  return s.substring(pos + 1);
 else            return s;

      • isInteger

        public static boolean isInteger​(java.lang.String s)
        Determines, efficiently, whether an input String is also an integer.

        NOTE: A leading plus-sign ('+') will, in fact, generate a FALSE return-value for this method.
        Parameters:
        s - Any java String
        Returns:
        TRUE if the input String is any integer, and false otherwise.

        NOTE: This method does not check whether the number, itself, will actually fit into a field or variable of type 'int'. For example, the input String '12345678901234567890' (a very large integer), though an integer from a mathematical perspective, is not a valid java 'int'. In such cases, TRUE is returned, but if Java's Integer.parseInt method were subsequently used, that method would throw an exception.

        NOTE: The primary purpose of this method is to avoid having to write try {} catch (NumberFormatException) code-blocks. Furthermore, if only a check is desired, and the String does not actually need to be converted to a number, this is also more efficient than actually performing the conversion.
        See Also:
        isInt(String)
        Code:
        Exact Method Body:
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         if (s == null) return false;

 int length = s.length();

 if (length == 0) return false;

 int i = 0;

 if (s.charAt(0) == '-')
 {
     if (length == 1) return false;
     i = 1;
 }

 while (i < length)
 {
     char c = s.charAt(i++);
     if (c < '0' || c > '9') return false;
 }

 return true;

      • isInt

        public static boolean isInt​(java.lang.String s)
        Convenience Method. Invokes isOfPrimitiveType(String, char[]). Passes ASCII characters that comprise Integer.MIN_VALUE (without a negative sign).
        Code:
        Exact Method Body:
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         return isOfPrimitiveType(s, INT_MIN_VALUE_DIGITS_AS_CHARS);

      • isLong

        public static boolean isLong​(java.lang.String s)
        Convenience Method. Invokes isOfPrimitiveType(String, char[]). Passes ASCII characters that comprise Long.MIN_VALUE (without a negative sign).
        Code:
        Exact Method Body:
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         return isOfPrimitiveType(s, LONG_MIN_VALUE_DIGITS_AS_CHARS);

      • isByte

        public static boolean isByte​(java.lang.String s)
        Convenience Method. Invokes isOfPrimitiveType(String, char[]). Passes ASCII characters that comprise Byte.MIN_VALUE (without a negative sign).
        Code:
        Exact Method Body:
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         return isOfPrimitiveType(s, BYTE_MIN_VALUE_DIGITS_AS_CHARS);

      • isShort

        public static boolean isShort​(java.lang.String s)
        Convenience Method. Invokes isOfPrimitiveType(String, char[]). Passes ASCII characters that comprise Short.MIN_VALUE (without a negative sign).
        Code:
        Exact Method Body:
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         return isOfPrimitiveType(s, SHORT_MIN_VALUE_DIGITS_AS_CHARS);

      • isOfPrimitiveType

        protected static boolean isOfPrimitiveType​(java.lang.String s,
                                           char[] minArr)
        Determines whether the input String is an integer in the range of Java's primitive type specified by an input char[] array parameter. Specifically, if the the input String is both a mathematical integer, and also an integer in the range of MIN_VALUE and MAX_VALUE for that primitive-type and then (and only then) will TRUE be returned.

        NOTE: The max and min values in the range of valid integers for the primitive type int (For Example) are 'int' are: -2147483648 ... 2147483647.

        ALSO: A leading plus-sign ('+') will, in fact, generate a FALSE return-value for this method.
        Parameters:
        s - Any Java String
        minArr - The value of a Java Primitive MIN_VALUE, without the minus-sign, represented as a char[] array.
        Primitive Type Integer as ASCII char[] array
        byte '2', '5', '6'
        short '6', '5', '5', '3', '6'
        int '2', '1', '4', '7,' '4', '8', '3', '6', '4', '8'
        long '2', '1', '4', '9', '2', '2', '3', '3', '7', '2', '0', '3', '6', '8', '5', '4', '7', '7', '5', '8', '0', '8'
        Returns:
        TRUE If the input String is both an integer, and also one which falls in the range comprised by the specified Java Primitive Type. Return FALSE otherwise.

        NOTE: The primary purpose of this method is to avoid having to write try {} catch (NumberFormatException) code-blocks. Furthermore, if only a check is desired, and the String does not actually need to be converted to a number, this is also more efficient than actually performing the conversion.
        See Also:
        isInteger(String), isInt(String), isByte(String), isLong(String), isShort(String)
        Code:
        Exact Method Body:
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         int length = s.length();

 // Zero length string's are not valid integers.
 if (length == 0)                                    return false;

 // A negative integer may begin with a minus-sign.
 boolean negative = s.charAt(0) == '-';

 // ****************************************************************************************
 // If the string is too short or too long, this method doesn't need to do any work.
 // We either know the answer immediately (too long), or we can call the simpler method
 // (in the case that it is too short)

 // If a string is shorter than (for type 'int', for example): 2147483647 (10 chars)
 // then we ought use the simplified method which just checks if the string is an integer.
 if (length < minArr.length)                         return isInteger(s);

 // If the string is longer than (for type 'int', for example): -2147483648 (11 chars)
 // then it cannot be an integer that fits into primitive 'int', so return false.
 if (length > (minArr.length + 1))                   return false;

 // If the String is *EXACTLY* 11 characters long (for primitive-type 'int', for example),
 // but doesn't begin with a negative sign, we also know the answer immediately.
 if ((!negative) && (length == (minArr.length + 1))) return false;

 // If the String *EXACTLY* the length of MAX_NUUMBER, but it begins with a negative sign,
 // we can call the simplified method, instead as well.
 if (negative && (length == minArr.length))          return isInteger(s);

 // The **REST** of the code is only executed if the numeric part of the String
 // (Specifically: leaving out the '-' negative sign, which may or may not be present)
 // ... if the numeric part of the String is precisely the length of MAX_VALUE / MAX_NUMBER
 // as determined by the length of the array 'minArr'...  If the input string is
 // **PRECISELY** that length, then the string must be checked in the loop below. 

 int     i                       = negative ? 1 : 0;
 int     j                       = 0;
 boolean guaranteedFitIfInteger  = false;
 char    c                       = 0;

 while (i < length)
 {
     c = s.charAt(i);

     if (! guaranteedFitIfInteger)
     {
         if (c > minArr[j]) return false;
         if (c < minArr[j]) guaranteedFitIfInteger = true;
     }

     if (c < '0') return false;
     if (c > '9') return false;

     i++; j++;
 }

 // THE COMMENT BELOW DELINEATES WHAT HAPPENS FOR THE INPUT-CASE OF PRIMITIVE-TYPE 'INT'
 // (2147483648)... But it generalizes for byte, short, and long as well.

 // This might seem very strange.  Since the MIN_VALUE ends with an '8', but the
 // MAX_VALUE ends with a '7', and since we are checking each character to see that
 // it falls within the array above, **RATHER THAN** just returning TRUE right here,
 // we have to catch the **LONE** border/edge case where some joker actually passed the
 // String 2147483648 - which must return FALSE, since the last positive integer is
 // 2147483647 (see that it has an ending of '7', rather than an '8').

 return guaranteedFitIfInteger || negative || (c != minArr[minArr.length-1]);