string.trim().length()的用法

 public class Test{
     public static void main(String args[]){
         String data = " a bc   ";
         //调用string中的方法trim().length()方法
         int trim = data.trim().length();
         System.out.println("the trim length is "+trim);

         int length = data.length();
         System.out.println("the length is "+length);
     }
 }

显示:

the trim length is 4
the length is 8

trim()方法的作用是去掉字符串头尾的空格