重写equals方法

public class Student {

    private String name;
    private String sex;
    private int age;

    // 重写equals
    public boolean equals(Object o) {
        if (this == o) {  //先判断内存地址
            return true;
        }
        if (!(o instanceof Student)) { //判断类型
            return false;
        }
        // 向下转型
        Student student = (Student) o;
        if (this.age == student.getAge() && this.name.equals(student.getName())
                && this.sex.equals(student.getSex())) {
            return true;
        } else {
            return false;
        }
    }

    public Student(String name, String sex, int age) {
        super();
        this.name = name;
        this.sex = sex;
        this.age = age;
    }

    public Student() {
        super();
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

}