重写equals方法

hibernate重写equals方法

public class User {
    private Integer id;
    private String username;
    private String password;
    private Integer age;
    public User() {
        super();
    }
    public User(Integer id, String username, String password, Integer age) {
        super();
        this.id = id;
        this.username = username;
        this.password = password;
        this.age = age;
    }
    
    
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    } 

@Override

    public boolean equals(Object obj) {
        if(obj==null)return false;
        if(this==obj)return true;
        if(obj instanceof User) {
            User u = (User) obj;
            return this.getId()==u.getId()
                    &&this.getUsername().equals(u.getUsername())
                    &&this.getPassword().equals(u.getPassword())
                    &&this.getAge()==u.getAge();
        }
        return false;
    }