Hi pooja,

StringBuffer
StringBuffer is used to store character string that will be changed. But string objects cannot be changed. It automatically expands as needed. Related classes- String, CharSequence.

StringBuilder
It is identical in all respects to StringBuffer except that it is not synchronized, which means that if multiple threads are accessing it at the same time, there could be trouble. For single-threaded programs, the most common case, avoiding the overhead of synchronization makes the StringBuilder very slightly faster.

import java.io.*;
import java.io.IOException;

public class StringBufferExample {

public static void main(String[] args) throws IOException{
BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please enter String Character!");
String st = buff.readLine();
StringBuffer sb =new StringBuffer(st);
System.out.println("Buffer = " +sb);
System.out.println("length is = " +sb.length());
System.out.println("Total capacity is = " +sb.capacity());

//appending and inserting into StringBuffer.
String str;
int a = 42;
StringBuffer buffer= new StringBuffer(40);
str = buffer.append("a=").append(a).append("!").toString();
System.out.println(str);
StringBuffer read = new StringBuffer("I JAVA.");
read.insert(2, "LIKE");
System.out.println(read);
}
}



import java.io.*;
import java.io.IOException;

public class StringBuilderExam{

public static void main(String[] args) throws IOException{
BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please enter string value!");
String st = buff.readLine();
StringBuilder build = new StringBuilder(st);
build.reverse();
System.out.println();
System.out.println("The reverce value is="+build);
}
}


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