Usage of super and this in Java

The code is relatively simple to say, look directly:

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classPerson {    publicstaticvoidprt(String s) {        System.out.println(s);    }    Person() {        prt("A Person.");    }    Person(String name) {        prt("A person name is:"+ name);    }}publicclassChinese extendsPerson {    Chinese() {        super(); // 调用父类构造函数（1）        prt("A chinese.");// (4)    }    Chinese(String name) {        super(name);// 调用父类具有相同形参的构造函数（2）        prt("his name is:"+ name);    }    Chinese(String name, intage) {        this(name);// 调用当前具有相同形参的构造函数（3）        prt("his age is:"+ age);    }    publicstaticvoidmain(String[] args) {        Chinese cn = newChinese();        cn = newChinese("kevin");        cn = newChinese("kevin", 22);    }}

The key is to look at (1), (2), (3), (4), this refers to the current object, so this (name) invokes the constructor that currently has the same formal parameter.

Super refers to the parent class object, so super (name) calls the constructor of the parent class with the same parameters.

The simpler this. Variable, refers to the variable of the current object. Super. Variable, which is the variable of the parent class

There's a little trick, the parent class name. This is the variable name/method name, at which point this refers to the parent class object.

Usage of super and this in Java