this super的用法
2018-05-21 16:40 yelena 阅读(171) 评论(0) 编辑 收藏 举报this关键词:谁调用代表谁
在构造函数中的应用格式:this(参数)
package com.oracle.Demo05; public class Animal { private String name; private int age; public Animal(){ } public Animal(String name){ this.name = name; } public Animal(String name,int age){ this(name); this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public void eat(){ System.out.println(name+age+"在吃饭"); } public void sleep(){ System.out.println(name+age+"在睡觉"); } }
成员变量和局部变量同名时的使用:
判断是否是同龄人问题
public boolean compare(Person p){ return this.age == p.age; }
this代表的是调用者
super关键字的使用
super和this 关键字都必须在第一行 所以两者不能同时出现
调用父类的构造函数
package com.oracle.Demo03; public class Person { private String name; private int age; public Person(){ } public Person(String name,int age){ this.name = name; this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } }
package com.oracle.Demo03; public class Student extends Person { public Student(){ } public Student(String name,int age){ super(name,age); } }
package com.oracle.Demo03; public class Worker extends Person { public Worker(){ } public Worker(String name,int age){ super(name,age); } }
调用父类的成员变量和成员方法