class Person
{
private String name;
private int age;
public void setPerson(String name,int age)
{
this.name=name;
this.age=age;
}
public void show()
{
System.out.println(name);
System.out.println(age);
}
}
class student extends Person
{
private int math,english;
public void Student(String name,int age,int m,int e)
{
super(name,age);
math=m;
english=e;
}
public void show()
{
System.out.println("name="+name);
System.out.println("age="+age);
System.out.println("math"+math);
System.out.println("english"+english);
}
public int total()
{
int total;
return total=math+english;
}
public void main(String[] args)
{
student s=new student();
s.Student("李四",18,70,85);
System.out.println("姓名："+name+"年龄："+age);
System.out.println("得分 数学："+math+" 英语："+english);
System.out.println("总分："+total());
}
}
对super调用必须是构造函数中第一个语句？super()应该怎么改
------解决方案--------------------------------------------------------
- Java code
开始--->父类的静态代码--->子类的静态代码-->父类的非静态代码--->父类构造函数--->子类非静态代码--->子类构造函数--->完成子类的构造函数的调用必须先完成父类的调用，这是系统初始化特性，所以super必须在构造方法中的第一句如果父类的不存在“有参构造方法”，此时写不写super无所谓，子类构造方法一定会调用super()，如果父类的 存在“有参构造方法”，此时必须指定是哪一个父类的构造方法
------解决方案--------------------------------------------------------
- Java code
class Person { public String name; public int age; public void setPerson(String name, int age) { this.name = name; this.age = age; } public void show() { System.out.println(name); System.out.println(age); }}public class Student extends Person { private int math, english; public void Student(String name, int age, int m, int e) { setPerson(name,age); math = m; english = e; } public void show() { System.out.println("name=" + name); System.out.println("age=" + age); System.out.println("math" + math); System.out.println("english" + english); } public int total() { int total; return total = math + english; } public static void main(String[] args) { Student s = new Student(); s.Student("李四", 18, 70, 85); System.out.println("姓名：" + s.name + "年龄：" + s.age); System.out.println("得分 数学：" + s.math + " 英语：" + s.english); System.out.println("总分：" + s.total()); }}