What is the difference between StringBuilder and StringBuffer?

Answer 1

StringBuilder is faster than StringBufferbecause it's not synchronized.
Here's a simple benchmark test:
public class Main { public static void main(String[] args) { int N = 77777777; long t; { StringBuffer sb = new StringBuffer(); t = System.currentTimeMillis(); for (int i = N; i --> 0 ;) { sb.append(""); } System.out.println(System.currentTimeMillis() - t); } { StringBuilder sb = new StringBuilder(); t = System.currentTimeMillis(); for (int i = N; i --> 0 ;) { sb.append(""); } System.out.println(System.currentTimeMillis() - t); } } }
↓↓↓ :)
https://stackoverflow.com/questions/355089/difference-between-stringbuilder-and-stringbuffer

Answer 2

stringbuffer is threadsafe, stringbuilder isnt but stringbuilder is faster.