JAVA-String 构造方法

package com.itheima;

public class string_01 {
    public static void main(String[] args) {
        String s1=new String();
        System.out.println(s1);
        System.out.println(s1.length());
        System.out.println("----------------------------");
        String s2=new String("itheima");//定义一个字符串类型
        System.out.println(s2);
        System.out.println(s2.length());
        String s3="itheima";//直接定义一个字符串类型
        System.out.println(s3.length());
    }
}

执行结果

0
----------------------------
itheima
7
7

Process finished with exit code 0