testmypoint.java

东软的java初级教程

public class TestMyPoint {
  public static void main(String[] args) {

    // Step 1: 定义对象start和end
    MyPoint start = new MyPoint();
    MyPoint end = new MyPoint();

    // Step 2: 给 start and end的属性赋值
    start.x = 10;
    start.y = 10;
    end.x = 20;
    end.y = 30;

    // Step 3: 输出start 和 end
    System.out.println("Start point is " + start.toString());
    System.out.println("End point is " + end.toString());
    System.out.println();

    // Step 5: 定义对象stray并赋值为对象 end，此时stray与end引用同一对象
    MyPoint stray = end;

    // Step 6: 输出stray和end
    System.out.println("Stray point is " + stray.toString());
    System.out.println("End point is " + end.toString());
    System.out.println();

    // Step 7: 给stray重新赋值
    stray.x = 47;
    stray.y = 50;
    System.out.println("Stray point is " + stray.toString());
    System.out.println("End point is " + end.toString());//stray的改变也影响end，因为end和stray引用同一对象
    System.out.println("Start point is " + start.toString());
  }
}