package com.student; //重写比较规则,判断Student两学员是否是同一个对象 //如果两学员的姓名学号相同则是同一个对象 public class Student { //学员属性 private String name; private int id; private String sex; /** * @param name * @param id */ public Student(String name, int id,String sex) { this.name = name; this.id = id; this.sex = sex; } //重写equals方法 public boolean equals(Object obj) { if(this == obj) { return true; } if(!(obj instanceof Student)) { return false; } Student s = (Student)obj; if(this.name.equals(s.name) && this.id==s.id) { return true; }else { return false; } } //重写equals方法 // public boolean equals(Object obj) { // if(obj instanceof Student) { // Student stu = (Student)obj; // if(this.name.equals(stu.name)&&this.id==stu.id) { // return true; // } // } // return false; // } //重写toStrint方法 public String toString() { return name; } //测试方法 public static void main(String[] args) { Student s1 = new Student("张三", 12,"男"); Student s2 = new Student("张三",12,"男"); System.out.println(s1 == s2); System.out.println(s1.equals(s2)); System.out.println(s1); String s = "bbb"; //打印输出s的时候默认调取了toString()方法 System.out.println(s); } }