String Buffer and String Builder

Education is not limited to just classrooms. It can be gained anytime, anywhere... - Ravi Ranjan (M.Tech-NIT)

Difference between String Buffer and String Builder

There are many differences between String Buffer and String Builder. A list of differences between String Buffer and String Builder are given below:

No. StringBuffer StringBuilder
1) StringBuffer is synchronized i.e. thread safe. It means two threads can't call the methods of StringBuffer simultaneously. StringBuilder is non-synchronized i.e. not thread safe. It means two threads can call the methods of StringBuilder simultaneously.
2) StringBuffer is less efficient than StringBuilder. StringBuilder is more efficient than StringBuffer.

String Buffer Example

  1. public class BufferTest{  
  2.     public static void main(String[] args){  
  3.         StringBuffer buffer=new StringBuffer("hello");  
  4.         buffer.append("java");  
  5.         System.out.println(buffer);  
  6.     }  
  7. }  
hellojava

String Builder Example

  1. public class BuilderTest{  
  2.     public static void main(String[] args){  
  3.         StringBuilder builder=new StringBuilder("hello");  
  4.         builder.append("java");  
  5.         System.out.println(builder);  
  6.     }  
  7. }  
hellojava

Performance Test of String Buffer and String Builder

Let's see the code to check the performance of String Buffer and String Builder classes.

  1. public class ConcatTest{  
  2.     public static void main(String[] args){  
  3.         long startTime = System.currentTimeMillis();  
  4.         StringBuffer sb = new StringBuffer("Java");  
  5.         for (int i=0; i<10000; i++){  
  6.             sb.append("Tpoint");  
  7.         }  
  8.         System.out.println("Time taken by StringBuffer: " + (System.currentTimeMillis() - startTime) + "ms");  
  9.         startTime = System.currentTimeMillis();  
  10.         StringBuilder sb2 = new StringBuilder("Java");  
  11.         for (int i=0; i<10000; i++){  
  12.             sb2.append("Tpoint");  
  13.         }  
  14.         System.out.println("Time taken by StringBuilder: " + (System.currentTimeMillis() - startTime) + "ms");  
  15.     }  
  16. }  
Time taken by StringBuffer: 16ms
Time taken by StringBuilder: 0ms