AppendStringTest.java

public class AppendStringTest{

  public static void main(String[] args){

    String text="";

 

    long beginTime=System.currentTimeMillis();

    for(int i=0;i<10000;i++)

      text =text+i;

 

    long endTime=System.currentTimeMillis();

    System.out.println("执行时间: "+(endTime-beginTime));

 

    StringBuilder builder=new StringBuider("");

    beginTime=System.currentTimeMillis();

    for(int i=0;i<10000;i++)

      builder.append(String.valueOf(i));

    endTime=System.currentTimeMillis();

    System.out.println("执行时间: "+(endTime-beginTime));

  }

}