问题详情

阅读以下说明和JAVA 2代码，将应填入(n)处的字句写在对应栏内。
[说明]
以下程序实现了在applet里移动图形文件，仔细阅读代码和相关注释，将程序补充完整。
[代码6-1]
import j ava. awt. *;
import j ava.awt.event.*;
import java.applet. Applet;
public class AppCIU extends Applet implements MouseMotionListener, MouseListener
{
Image IMG nClick=over(this) title=放大; // 声明 Image 类类型的变量 IMG nClick=over(this) title=放大
int x=70,y=60,posX=70,posY=60,dx,dy;
public void init ()
{
IMG nClick=over(this) title=放大=getImage (getCodeBase () ,"mouse.gif" ); //载入影像
addMouseListener (this );
addMouseMotionListener (this );
}
public void mousePressed (MouseEvent e )
{
dx=e.getX()-posX； //取得按下之点与基准点X方向的距离
dy=e.getY()-posY； //取得按下之点与基准点Y方向的距离
}
public void mouseDragged (MouseEvent e )
{
(1)
(2)
if (dx＞0 && dx＜120 && dy＞0 && dy＜60 ) //如果指针落在图形上方
{
Graphics g=getGraphics ();
(3)
}
}
public void paint (Graphics g )
{
(4)
(5)
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}
public void mouseMoved (MouseEvent e ) {};
public void mouseReleased (MouseEvent e ) {};
public void mouseEntered (MouseEvent e ) {};
public void mouseExited (MouseEvent e ) {};
public void mouseClicked (MouseEvent e ) {};
}请帮忙给出正确答案和分析，谢谢！