Java Tutorial/Apache Common/StringUtils

SplitString

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
        //Split a String into an Array using # as seperator.
        String [] splitArr=StringUtils.split("AB#CD#EF#GH", "#");
        
        for(int i=0; i<splitArr.length; i++ ) {
            System.out.println( i + ") "+ splitArr[i]);
        }
    }
}

0) AB
1) CD
2) EF
3) GH

String Escape

import org.apache.rumons.lang.StringEscapeUtils;
public class MainClass {
    public static void main(String[] args) {
        String strHTMLInput = "<P>MyName<P>";
        String strEscapeHTML = StringEscapeUtils.escapeHtml(strHTMLInput);
        String strUnEscapeHTML = StringEscapeUtils.unescapeHtml(strEscapeHTML);
        System.out.println("Escaped HTML >>> " + strEscapeHTML);
        System.out.println("UnEscaped HTML >>> " + strUnEscapeHTML);
    }
}

StringUtils.abbreviate

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
        //String can be max 12 chars including the ...
        System.out.println("1) Abbreviate Once upon a time >>>" +
            StringUtils.abbreviate("Once upon a time ", 12));
    }
}

1) Abbreviate Once upon a time >>>Once upon...

StringUtils.chomp

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Remove the specified string at the end of String
      System.out.println("3) Chomp END >>>" +
          StringUtils.chomp("A test String END", "END"));


    }
}

3) Chomp END >>>A test String

StringUtils.containsNone

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Check that a string does not contain any of these characters !@#$%^&*
      System.out.println("14) Check that ABCD contains none of !@#$%^&* >>>" +
          StringUtils.containsNone("ABCD", "!@#$%^&*"));
    }
}

14) Check that ABCD contains none of !@#$%^&* >>>true

StringUtils.containsOnly

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Check if string contains only a specified set of characters. Return boolean
      System.out.println("4) Check if 643287460 contains only 0123456789 >>>" +
          StringUtils.containsOnly("643287460", "0123456789"));
    }
}

4) Check if 643287460 contains only 0123456789 >>>true

StringUtils.defaultString

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Takes Object input and returns Empty String if null.
      System.out.println("6) Return default string >>>" + "**" +
          StringUtils.defaultString(null) + "**");
    }
}

6) Return default string >>>****

StringUtils.difference

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Compare two strings. Case Sensitive
      System.out.println("5) Compare ABCDEFG and ABCdefg >>>" +
          StringUtils.difference("ABCDEFG", "ABCdefg"));
    }
}

5) Compare ABCDEFG and ABCdefg >>>defg

StringUtils.equals

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Compare Strings...No NullPointer Exception!
      System.out.println("12) Comapre null and null >>>" +
          StringUtils.equals(null, null));

    }
}

12) Comapre null and null >>>true

StringUtils.indexOfDifference

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Returns index where the Strings start to differ
      System.out.println(
          "2) Index Of Difference between ABCXYZ and ABCPQR >>>" +
          StringUtils.indexOfDifference("ABCXYZ", "ABCPQR"));

    }
}

2) Index Of Difference between ABCXYZ and ABCPQR >>>3

StringUtils.join

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Join all Strings in the Array into a Single String, separated by $#$ 
      System.out.println("7) Join Strings using separator >>>" +
          StringUtils.join(new String[] { "AB", "CD", "EF" }, "$#$"));
    }
}

7) Join Strings using separator >>>AB$#$CD$#$EF

StringUtils.reverse

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Reverse a String
      System.out.println("9) Reverse >>>" + StringUtils.reverse("REVERSE"));
    }
}

9) Reverse >>>ESREVER

StringUtils.stripToEmpty

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //Strip whitespace from start and end of the string.
      //If null returns empty string
      System.out.println("13) Strip whitespace >>>" +
          StringUtils.stripToEmpty("     ABCD      "));
    }
}

13) Strip whitespace >>>ABCD

StringUtils.substring

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //SubString
      System.out.println("8) Substring >>>" +
          StringUtils.substring("SUBSTRING", 1, 5));
    }
}

8) Substring >>>UBST

StringUtils.trim

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //No NullPointer Exception even if null!
      System.out.println("10) Trim String. No NullPointerException >>>" +
          StringUtils.trim(null));
    }
}

10) Trim String. No NullPointerException >>>null

StringUtils.trimToEmpty

import org.apache.rumons.lang.StringUtils;
public class MainClass {
    public static void main(String[] args) {
      //If string is null, empty string returned. Else returns trimmed string
      System.out.println("11) Empty String >>>" +
          StringUtils.trimToEmpty(null) + "<<<");

    }
}

11) Empty String >>><<<