java代码,继承。。。主要是传值,赋值。

总结:总是忘记前面的方法:

package com.asdf;

public class RR {
	String name;
	int age;

	public RR() {
		name = "zhangsan";
		age = 232;
	}

	public RR(String a, int b) {
		name = a;
		age = b;
	}

	public void print() {
		System.out.println("我叫:" + name + ",今年:" + age + "岁");
	}

}

class Word extends RR {
	String color;
	int classno;
	String name;

	// 普通的成员方法都不会了。。操
	public void setColor(String color) {
		this.color = color;
	}

	public String getColor() {
		return color;
	}

	public Word() {
		super("刘德华", 22);
		name = "周杰伦";
		classno = 4;
		age = 2;// age是父类的属性,它是公共成员变量
		// color="whiteS";
	}

	public Word(String name, int age, int classno, String color) {
		this.color = color;
		this.name = name;
		this.age = age;
		this.classno = classno;
	}// set是设置属性,get是获取方法属性

	public void read() {

		System.out.println("我的姓名:" + name + ",年龄是:" + age + ",课程编号:" + classno
				+ "父类的成员变量" + super.name + "这颜色是;" + this.getColor());
	}

	public String toString() {
		return "这是" + color + "颜色";
	}
}


package com.asdf;

public class Test {
	public static void main(String[] args) {
		Word w = new Word();
		RR a = new Word();
		a.print();
		w.setColor("blue");// 这里传了参数,所以在子类的带参的构造方法里一定要传入参数,否则不能赋值
		w.read();

		System.out.println(w.toString());
		// System.out.println(w.setColor("blue"));
		// 这里多态为什么不能调用子类的方法
		// ((Word)a).read();
		// System.out.println("这是普通的方法"+w.color);
		// System.out.println(a.toString());
		/*
		 * w.print(); w.read(); System.out.println(w.toString());
		 */
	}

}

  

原文地址:https://www.cnblogs.com/langlove/p/3439361.html