Strings and String methods in Java

String type variable  contain collection of character. Basically string is used to storing text.

Syntax:

String name = "SudaisAli";

Different ways to print statement in java

System.out.print();   // No new Line At end
System.out.println(); // New line at end
System.out.printf();  // Print statment with Escape Sequence
System.out.format();  // Print statment with Escape Sequence

In java string is a object which can perform various functions

charAt()

String s1="sudais";  
System.out.println(s1.charAt(4));

Output :  i

compareToIgnoreCase() or equals()

String s1="sudais"; 
String s2="SUDAIS"; 
System.out.println(s1.equalsIgnoreCase(s2)); 
System.out.println(s1.equals(s2));

Output :  true

Output :  false

trim()

String s1="Sudais ";  
System.out.println(s1+"Ali");//without trim()  
System.out.println(s1.trim()+"Ali");//with trim()  

Output :  Sudais Ali

Output :  SudaisAli

toUpperCase()

 String name = "SudaisAli";
System.out.println(name.toUpperCase());

Output :  SUDAISALI

toLowerCase()

String name = "SudaisAli";
System.out.println(name.toLowerCase());

Output :  sudaisali

isEmpty()

String s1="";  
String s2="sudais";  
System.out.println(s1.isEmpty());  
System.out.println(s2.isEmpty()); 

Output :  true

Output :  false

Length()

String name = "SudaisAli";
System.out.println("The length of the txt string is: " + name.length());

 

Output :The length of the txt string is: 8

Example Program

public class Strings {
 public static void main(String[] args) {
    String name = "My name is sudais Bin Sohail";
    System.out.println(name);
    System.out.println("Lowe Case : "+name.toLowerCase());
    System.out.println("Upper Case : "+name.toUpperCase());
    System.out.println("Ends with : "+name.endsWith("Sohail"));
    System.out.println("Concatination : "+name.concat(" Welcome"));
    System.out.println("Character at Index : "+name.charAt(8));
    System.out.println("Is empty : "+name.isEmpty());
    System.out.println("Replace character : "+name.replace('s','m'));
    }
    
}

Out Put :

My name is sudais Bin Sohail

Lower Case : my name is sudais bin sohail

Upper Case : MY NAME IS SUDAIS BIN SOHAIL

Ends with : true

Concatination : My name is sudais Bin Sohail Welcome

Character at Index : i

Is empty : false

Replace character : My name im mudaim Bin Sohail

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