How to use Java construction method super and custom exception throw collection

1.Construction method:

public class name (){} Make a distinction // public void method name (){}<br> is divided into parameterized and parameterless. Class construction method

public class Zi extends fu{

    public int message=35;



public Zi(){

    System.out.println("我是谁");
}}

When creating an object: It will output: Contents in the subclass construction method:

2. Use of super and this:

 public void show(int message)
    {
        System.out.println(this.message);//返回本类的成员变量
        System.out.println(super.message);//返回父类的成员变量
    }

3. Use the construction method:

 public Zi(int name){

System.out.println(name);


    }

public fu(int name){

        System.out.println(name);
    }

 Zi sw=new Zi(200);   //    带参的：访问带参的子类带参构造方法

The subclass needs to add a super(name);
can pass Create a subclass object: return the parameterized constructor of the subclass, and return the parameterized constructor of the parent class
Without addition, you can only return the parameterized constructor of the subclass, and return the parameterless constructor of the parent class
So:

 public Zi(int name){

super(name);      //加这个
System.out.println(name);


    }

4. Custom exception throw: (Supplementary)

public class Student {




    public void sctrr(int score) throws uytig{
if(score<0||score>100){
        throw new uytig(); //throw  异常对象



    }
else {
    System.out.println("方法异常！");

}}}

public class uytig extends Exception{


    public  uytig(){
        super();

    }

public  uytig(String message){
    super();

// public Exception(String message) {
//        super(message);
//    }
    // public Throwable(String message) {
    //        fillInStackTrace();
    //        detailMessage = message;
    //    }
}

public class fu {


    public static void main(String[] args) throws uytig{


        Student sc=new Student();


        try {
            sc.sctrr(98);
        } catch (uytig uytig) {
            uytig.printStackTrace();
        }


    }
}

Input score=120;
Print: Error location
uytig<br>at Student.sctrr(Student.java:10)<br>at fu.main(fu.java:11)

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