Super in java can be used to access the constructor method of the super class and the methods hidden by the subclass.
super is a reference to the parent class. If the constructor does not explicitly call the constructor of the parent class, the compiler will automatically Add a default super() method call to it.
Assuming that there is a method in the subclass with the same name and parameters as the method in the superclass, then the method in the superclass will be hidden, that is to say, it will be overloaded in the subclass (note: methods with the same name and different parameters Functions or methods are called overloading. The original text "There are methods in the subclass with the same names and parameters as those in the superclass... overloading" is wrong) refers to the methods in the parent class. (Recommended learning: java course)
The syntax format hidden in the reference parent class is as follows:
super (parameter list) or super .Method name (parameter list)
The following code shows how to use super:
package cn.demo;
public class Demo1 {
public static void main(String[] args) {
SubClass_A sc=new SubClass_A(2,3);
System.out.println(sc.i);// 3
System.out.println(sc.j);// 1
}
}
class SuperClass_A
{
public int i=0;
public int j=0;
public SuperClass_A()
{
j=1;
}
}
class SubClass_A extends SuperClass_A
{
public int i;
SubClass_A(int a,int b)
{
super();
i=b;
}
}The above is the detailed content of java what is super. For more information, please follow other related articles on the PHP Chinese website!
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