String funtion in java

Java String provides a lot of concepts that can be performed on a string such as compare, concat, equals, split, length, replace, compareto, intern, substring etc.

Syntex:

String str = "Hello India!";

e.g

public class StrDemo{

   public static void main(String args[]){
      char[] indiaArray = { 'I', 'n', 'd', 'i', 'a', '!'};
      String indiaString = new String(indiaArray);  
      System.out.println( indiaString );
   }
} 

output: India!

 String Methods:

	Syntex	Description
1	char charAt(int index)	returns char value for the particular index
2	int length()	returns string length
3	static String format(String format, Object... args)	returns formatted string
4	static String format(Locale l, String format, Object... args)	returns formatted string with given locale
5	String substring(int beginIndex)	returns substring for given begin index
6	String substring(int beginIndex, int endIndex)	returns substring for given begin index and end index
7	boolean contains(CharSequence s)	returns true or false after matching the sequence of char value
8	static String join(CharSequence delimiter, CharSequence... elements)	returns a joined string
9	static String join(CharSequence delimiter, Iterable<? extends CharSequence> elements)	returns a joined string
10	boolean equals(Object another)	checks the equality of string with object
11	boolean isEmpty()	checks if string is empty
12	String concat(String str)	concatinates specified string
13	String replace(char old, char new)	replaces all occurrences of specified char value
14	String replace(CharSequence old, CharSequence new)	replaces all occurrences of specified CharSequence
15	String trim()	returns trimmed string omitting leading and trailing spaces
16	String split(String regex)	returns splitted string matching regex
17	String split(String regex, int limit)	returns splitted string matching regex and limit
18	String intern()	returns interned string
19	int indexOf(int ch)	returns specified char value index
20	int indexOf(int ch, int fromIndex)	returns specified char value index starting with given index
21	int indexOf(String substring)	returns specified substring index
22	int indexOf(String substring, int fromIndex)	returns specified substring index starting with given index
23	String toLowerCase()	returns string in lowercase.
24	String toLowerCase(Locale l)	returns string in lowercase using specified locale.
25	String toUpperCase()	returns string in uppercase.
26	String toUpperCase(Locale l)	returns string in uppercase using specified locale.

Ex.
1. char charAt(int index):-
 public class CharAt{  // class declaration
public static void main(String args[]){
String name="Knowledge Hunt";  // string initialization
char ch=name.charAt(10);//returns the char value at the 10th index
System.out.println(ch);
}}
// Output : H
 2. int length()
public class Strlength{ 
public static void main(String args[]){ 
    String Str1 = new String("Knowledge Hunt");
   
    System.out.print("String Length :" );
    System.out.println(Str1.length()); 
}}
//out put:  String Length :14
3. static String format(String format, Object... args)

public class StringFromatExample {     public static void main(String[] args) {                 System.out.printf("%-12s%-12s%s\n","Column 1","Column 2","Column3");         System.out.printf("%-12d%-12d%07d\n",15,12,5);     } } output:// Column 1    Column 2    Column3 15          12          0000005 5. String substring(int beginIndex) public class Test{    public static void main(String args[]){       String Str = new String("Knowledge Hunt");       System.out.print("Return Value :" );       System.out.println(Str.substring(10) );       System.out.print("Return Value :" );       System.out.println(Str.substring(0, 10) );    } } output: Return Value :Hunt Return Value :Knowledge