holderex2.java

JAVA编程思想第四版英文原版习题答案. pdf原版的

// generics/HolderEx2.java
// TIJ4 Chapter Generics, Exercise 2, page 621
/* Create a holder class that holds three objects of the same type along 
* with the methods to store and fetch those objects and a constructor to 
* initialize all three.
*/ 
import typeinfo.pets.*;

class Robot {
	private String name;
	public Robot(String name) { this.name = name; }
	public String toString() { 
		return name;
	}
}

public class HolderEx2<T> {
	private T x, y, z;
	public HolderEx2(T x, T y, T z) { 
		this.x = x;
		this.y = y;
		this.z = z;
	 }
	public void setX(T x) { this.x = x; }
	public void setY(T y) { this.y = y; }
	public void setZ(T z) { this.z = z; }
	public T getX() { return x; }
	public T getY() { return y; }
	public T getZ() { return z; }
	public String toString() {
		return x + ", " + y + ", " + z;
	}
	public static void main(String[] args) {
		Robot a = new Robot("bot1");
		Robot b = new Robot("bot2");
		Robot c = new Robot("bot3");
		HolderEx2<Robot> hEx2 = 
			new HolderEx2<Robot>(a, b, c);
		System.out.println("Holding: " + hEx2);
	}
}