问答题下面Applet程序的功能是统计在平面坐标系第一象限中，半径大于9，小于10的圆环中坐标值为整数的点有多少?并且给出其坐标值。请改正程序中的错误(有下画线的语句)，使程序执行后，能得到预期的结果。
import java.awt.*；
import java.applet.*；
/*
＜applet code=Di9Ti width=200 height=100＞
＜/applet＞
*/
public class Di9Ti extends Applet
{
public void paint(Graphics g)
{
int x,y,r1=5,r2=4；
int count=0；
for(x=1；x＜y；x++)
{
for(y=1；y＜r1；y)
{
if(x*x+y*y＜=r2*r2||x*x+y*y＞=r1*r1)
{{U}}break{{/U}}；
g.drawStdng("x="+x+"y="+y，20+count*80,20)；
count++；
}
}
g.drawString("count="+count,20,40)；
}
}
ex11_3.html：
＜html＞
＜head＞
＜title＞A Simple Program＜/title＞
＜/head＞
＜body＞
＜applet code="Di9Ti.class"width=800 height=400＞
＜/applet＞
＜／body＞
＜／html＞
问答题本程序中，当鼠标在窗口上单击左键时，则以单击的点为圆心画一个小圆，如果单击右键，则以单击的点为中心画一个正方形，当鼠标离开窗口时，窗口上的所有图形将清除掉，如图所示。importjava.awt.*;importjava.awt.event.*;classMyCanvasextendsCanvasimplementsMouseListener{intleft=-1,right=-1;intx=-1,y=-1;MyCanvas(){setSize(100,100);addMouseListener(this);}publicvoidpaint(GraPhicsg){if(left==1){g.drawOval(x-10,y-10,20,20);}elseif(right==1){g.drawRect(x-8,y-8,16,16);}}publicvoidmousePressed(MouseEvente){x=e.getX();y=e.getY();if(e.getModifiers()==______){left=l;right=-1;repaint();}elseif(e.getModifiers()==______){right=1;left=-1;repaint();}}publicvoidmouseReleased(MouseEvente){}publicvoidmouseEntered(MouseEvente){}publicvoidmouseExited(MouseEvente){left=-1;right=-1;repaint();}publicvoidmouseClicked(MouseEvente){}publicvoidupdate(Graphicsg){if(left==1||right==1){paint(g);}else{super.update(g);}}}publicclassexam_92{publicstaticvoidmain(Stringargs[]){Framef=newFrame();f.setTitle("exam_92");f.setBounds(100,100,200,200);f.setVisible(true);f.addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente]{System.exit(0);}});f.add(newMyCanvas(),BorderLayout.CENTER);f.validate();}}
问答题本程序计算3位整数365的个位、十位、百位的数，并分别打印输出。
public class exam_36{
public static void main(String[] args){
int num=365;
int a, b, c;
int temp=num;
______;
temp=temp-a*100;
______;
______;
System.out.println(num+":百位数:"+a+", 十位数:"+b+", 个位数:"+c);
}
}
问答题System.out.println(i+ " ! =" + 1Factorial)；
问答题System. out. print in (a+"的最大真约数为: "+i );
问答题本程序用弹出窗口来选择在主窗口绘制的图形。在“控制窗口”中有三个单选按钮，用来选择绘制的图形，复选框来确定绘制的图形是否是填充的，三个下拉菜单分别控制颜色、字体和文字的大小，一个文本框用来输入添加的文本，一个按钮用来清除主窗口中的内容。在主窗口中拖动鼠标可以绘制选定的图形，在文本框中输入字符串后回车，然后在主窗口中单击鼠标，就能将字符串添加到画板中，如图所示。importjava.awt.*;importjava.awt.event.*;importjavax.swing.*;importjavax.swing.event.*;publicclassexam_92extendsJFrame{privateinttopX,topY,width,fontSize,height,bottomX,bottomY,shape;privatebooleanclear,textOn,filled;privateColordrawingColor;privateStringfont;privateJTextFieldtext;privateJPanelpanel1,panel2,panel3,panel4;privateJRadioButtonovalBox,rectBox,lineBox;privateButtonGroupshapeGroup;privateJCheckBoxfillBox;privateJComboBoxcolorList,fontList,sizeList;privateJButtonclearButton;privateStringcolorNames[]={"Black","Green","Blue","Red","Cyan"};privateColorcolors[]={Color.black,Color.green,Color.blue,Color.red,Color.cyan};privateStringfontNames[]={"Serif","SansSerif","Monospaced"};privateStringsizeNames[]={"9","10","22","72"};privateintsizes[]={9,10,22,72};privatefinalintOVAL=1,LINE=2,RECT=3;privateToolWindowtools;publicexam_92(){super("exam_92");addMouseListener(newMouseHandler());drawingColor=Color.black;shape=OVAL;font="Serif";fontSize=9;setDefaultCloseOperation(EXIT_ON_CLOSE);setBackground(Color.white);setSize(300,300);show();tools=newToolWindow();}publicvoidpaint(Graphicsg){g.setColor(drawingColor);if(textOn){g.setFont(newFont(font,Font.PLAIN,fontSize));g.drawString(text.getText(),topX,topY);textOn=false;return;}if(shape!=LINE){topX=Math.min(topX,bottomX);topY=Math.min(topY,bottomY);}if(filledbreak;caseRECT:g.fillRect(topX,topY,width,height);break;}elseswitch(shape){caseOVAL:g.drawOval(topX,topY,width,height);break;caseLINE:g.drawLine(topX,topY,bottomX,bottomY);break;caseRECT:g.drawRect(topX,topY,width,height);break;}if(clear==true){g.setColor(Color.white);g.fillArea(0,0,getSize().width,getSize().height);clear=false;}}privateclassToolWindowextendsJFrame{publicToolWindow(){super("控制窗口");text=newJTextField("Text",25);text.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEventevent){textOn=true;repaint();}});fontList=newJComboBox(fontNames);fontList.setMaximumRowCount(3);fontList.addItemListener(newItemListener(){publicvoiditemStateChanged(ItemEventevent){font=fontNames[fontList.getSelectedIndex()];}});sizeList=newJComboBox(sizeNames);sizeList.setMaximumRowCount(3);sizeList.addItemListener(newItemListener(){publicvoiditemStatedChanged(ItemEventevent)fontSize=sizes[sizeList.getSelectedIndex()];}});colorList=newJComboBox(colorNames);colorList.setMaximumRowCount(3);colorList.addItemListener(newItemListener(){publicvoiditemStateChanged(ItemEventevent){drawingColor=colors[colorList.getSelectedIndex()];}});clearButton=newJButton("Clear");clearButton.addActionListener(newClearButtonHandler());fillBox=newJCheckBox("Filled");FillBoxHandlerfillHandle=newFillBoxHandler();fillBox.addItemListener(fillHandle);ovalBox=newJRadioButton("Oval",true);lineBox=newJRadioButton("Line",false);rectBox=newJRadioButton("Rectangle",false);RadioButtonHandlerhandler=newRadioButtonHandler();ovalBox.addItemListener(handler);lineBox.addItemListener(handler);rectBox.addItemListener(handler);shapeGroup=newButtonGroup();shapeGroup.add(ovalBox);shapeGroup.add(lineBox);shapeGroup.add(rectBox);panel1=newJPanel();panel2=newJPanel();panel3=newJPanel();panel4=newJPanel();panel1.setLayout(newGridLayout(1,4));panel2.setLayout(newGridLayout(1,3));panel3.setLayout(newFlowLayout());panel4.setLayout(newFlowLayout());panel1.add(ovalBox);panel1.add(lineBox);panel1.add(rectBox);panel1.add(fillBox);panel2.add(newJScrollPane(colorList));panel2.add(newJScrollPane(fontList));panel2.add(newJScrollPane(sizeList));panel3.add(text);panel4.add(clearButton);Containercontainer=getContentPane();container.setLayout(newFlowLayout());container.add(panel1);container.add(panel2);container.add(panel3);container.add(panel4);setDefaultCloseOperation(EXIT_ON_CLOSE);setSize(350,175);setLocation(300,0);setVisible(true);}}privateclassMouseHandlerextendsmouseAdapter{publicvoidmousePressed(MouseEventevent){topX=event.getX();topY=event.getY();}publicvoidmouseReleased(MouseEventevent){bottomX=event.getX();bottomY=event.getY();width=Math.abs(topX-bottomX);height=Math.abs(topY-bottomY);repaint();}}privateclassClearButtonHandlerimplementsActionListener{publicvoidactionPerformed(ActionEventevent){clear=true;repaint();}}privateclassRadioButtonHandlerimplementsItemListener{publicvoiditemStateChanged(ItemEventevent){if(event.getSource()==ovalBox)shape=OVAL;elseif(event.getSource()==lineBox)shape=LINE;elseif(event.getSource()==rectBox)shape=RECT;}}privateclassFillBoxHandlerimplementsItemListener{publicvoiditemStateChanged(ItemEventevent){if(event.getStateChange()==ItemEvent.SELECTED)filled=true;elsefilled=false;}}publicstaticvoidmain(Stringargs[]){exam_92application=newexam_92();application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);}}
问答题请完成下列Java程序：查找一个矩阵中的鞍点，对于一个二维数组中的鞍点，该点位置上的元素在该行上最小，在该列上最大，也可能没有鞍点。数组大小为4行5列。
注意：请勿改动main()主方法和其他已有语句内容，仅在下划线处填入适当的语句。
public class ex30_2 {
public static void main(String[] args) {
int i, j, flag,m=4,n=5;
int[] min=new int [4];
int[] max=new int [5];
int r[] []={{2,5,6,7,9},
{32,65,2,78,12},
{1,8,5,96,4},
{5,3,21,73,23}};
flag=0;
for (i=0; i＜m; i++) {//获取元素在该行上最大
min[i]=r[i] [0];
for (j=1; j＜n; j++)
if(r[i] [j]＜min[i])
___________________;
}
for (j = 0; j ＜n; j ++ ) { //获取同一元素在该列上最大
max[j]=r[0] [j];
for(i=l;i＜m;i++)
if(r[i] [j]＞max[j])
_______________________
}
for(i=0;i＜m;i++)
for(j=0;j＜n;j++)
if(min[i]==max[j]){
System.out.print("("+i+", "+j+") : "+r[i] [j]);
flag=1;
}
if(flag==0)
System.out.println("没有鞍点!");
}
}
问答题本程序在窗口上添加一个水平的带有刻度的滑动条，刻度值的范围是0～100，跨度为20，并且当前滑块的位置在40刻度处，如图所示。importjavax.swing.*;importjava.awt.event.*;publicclassexam_56extendsJFrame{JPaneljpanel1;JSliderjslider1;publicexam_56(){super("exam_56");setSize(300,120);jpanel1=newJPanel();jslider1=newJSlider(jslider1.HORIZONTAL,______);jslider1.setMajorTickSpacing(______);jslider1.setPaintTicks(true);jslider1.setPaintLabels(true);jpanel1.add(jslider1);this.setContentPane(jpanel1);}publicstaticvoidmain(String[]a){exam_56ts=newexam_56();ts.show();ts.addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});}}
问答题本程序中，通过菜单Connect显示一个对话框，对话框中有“Username”和“Password”两个文本框，在这两个文本框中输入内容后单击“Ok”按钮，在主窗口的下面就会显示所填写的内容。例如在“Username”文本框中填写“Joun”，在“Password”文本框中填写“19820201”，单击“Ok”按钮后，在主窗口的下面就会显示出“username=Joun,password=19820201”，如图所示。importjava.awt.*;importjava.awt.event.*;importjavax.swing.*;publicclassexam_14extendsJFrameimplementsActionListener{publicexam_14(){setTitle("exam_14");setSize(300,300);addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});______;setJMenuBar(mbar);JMenufileMenu=newJMenu("File");mbar.add(fileMenu);connectItem=newJMenuItem("Connect");connectItem.addActionListener(this);fileMenu.add(connectItem);exitItem=newJMenuItem("Exit");exitItem.addActionListener(this);fileMenu.add(exitItem);}publicvoidactionPerformed(ActionEventevt){Objectsource=evt.getSource();if(source==connectItem){ConnectInfotransfer=newConnectInfo("yourname","pw");if(dialog==null)dialog=newConnectDialog(this);if(dialog.showDialog(transfer)){Stringuname=transfer.username;Stringpwd=transfer.password;ContainercontentPane=getContentPane();contentPane.add(newJLabel("username="+uname+",password="+pwd),"South");validate();}}elseif(source==exitItem)System.exit(0);}publicstaticvoidmain(String[]args){JFramef=newexam_14();f.show();}privateConnectDialogdialog=null;privateJMenuItemconnectItem;privateJMenuItemexitItem;}classConnectInfo{publicStringusername;publicStringpassword;publicConnectInfo(Stringu,Stringp){username=u;password=p;}}classConnectDialogextendsJDialogimplementsActionListener{publicConnectDialog(JFrameparent){super(parent,"Connect",true);ContainercontentPane=getContentPane();JPanelp1=newJPanel();p1.setLayout(newGridLayout(2,2));p1.add(newJLabel("Username:"));p1.add(username=newJTextField(""));p1.add(newJLabel("Password:"));p1.add(password=newJPasswordField(""));contentPane.add("Center",p1);Panelp2=newPanel();okButton=addButton(p2,"Ok");cancelButton=addButton(p2,"Cancel");contentPane.add("South",p2);setSize(240,120);}JButtonaddButton(Containerc,Stringname){JButtonbutton=newJButton(name);button.addActionListener(this);c.add(button);______;}publicvoidactionPerformed(ActionEventevt){Objectsource=evt.getSource();if(source==okButton){ok=true;setVisible(false);}elseif(source==cancelButton)setVisible(false);}publicbooleanshowDialog(ConnectInfotransfer){username.setText(transfer.username);password.setText(transfer.password);ok=false;show();if(ok){transfer.username=username.getText();transfer.password=newString(password.getPassword());}returnok;}privateJTextFieldusername;privateJPasswordFieldpassword;privatebooleanok;privateJButtonokButton;privateJButtoncancelButton;}
问答题注意：下面出现的“考生文件夹”均为%USER%。在考生文件夹中存有文件名为Java_1.java的文件，该程序是不完整的，请在注释行“//**********Found**********”下一行语句的下画线地方填入正确内容，然后删除下画线，请勿删除注释行或改动其他已有语句内容。存盘时文件必须存放在考生文件夹下，不得改变原有文件的文件名。本题的要求是：完善Java_1.java程序，并完成两个整数的输入，两个整数为运行结果为：最后单击“确定”按钮退出程序。给定源程序：//计算两个整数的乘法importjavax.swing.JOptionPane;publicclassJava_1publicstaticvoidmain(stringargs[])intx,y,result;StringxVal,yVal;xVal=JOptionPane.showInputDialog("输入第1个整数:");yVal=JOptionPane.showInputDialog("输入第2个整数:");//*********Found********x=Integer.parseInt(______);y=Integer.parseInt(yVal);result=x*y;//*********Found********JOptionPane.______(null,"两个数的积:"+result);System.exit(0);
问答题__________
问答题请完成下列Java程序。程序的功能是复制文件并显示文件，将每个字符读入，并写入另一个文件，同时显示出来。(注意：在本题中，是将D盘的JDK目录下的README.txt文件打印在屏幕上，并写入另一个文件temp.txt中)
注童：请勿改动main()主方法和其他已有的语句内容，仅在下划线处填入适当的语句。
import java.io.*；
public class FileCopyBy{
public static void main(String args[]){
try{
FileReader input=new FileReader("FileCopyBy.java")；
FileWriter output=new FileWriter("temp.txt")；
int c=input.read()；
while(__________)
{
_______________
System.out.print((char}c)；
c=input.read()；
}
input.close()；
output，close()；
}
catch(IOException e)
{
System.out.println(e)；
}
}
}
问答题下面是实现用户界面程序的一个例子，请在画线处填写适当语句，使程序能正确执行。
import javax.swing.JFileChooser;
import javax.swing.JTextArea;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.event.*;
import java.io.*;
import java.awt.*;
public class SwingExample3 implements ActionListener{
private JFrame frame;
private JButton button;
private JButton saveButton;
private JTextArea textArea;
private JFileChooser dia;
private JPanel buttonPanel;
public void initGUI(){
frame=new JFrame("file chooser");
button=new JButton("open file");
button.setActionCommand("open");
button.addActionListener(this);
saveButton=new JButton("save file")；
saveButton.setActionCommand("save");
saveButton.addActionListener(this);
textArea=new JTextArea(" ",10,10);
buttonPanel=new JPanel();
dia=new JFileChooser();
frame.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);}
});
buttonPanel.add(button);
buttonPanel.add(saveButton);
frame.getContentPane().add(buttonPanel,BorderLayout.NORTH);
frame.getContentPane().add(textArea,BorderLayout.CENTER);
frame.setSize(200,200);
frame.setVisible(true);
public void actionPerformed(ActionEvent event){
if(event.getActionCommand().equals("open")){
//打开文件
dia.showOpenDialog(frame);
dia.setVisible(true);
File file=dia.getSelectedFile();
String fileName=file.getAbsolutePath();
textArea.append("path of selected file:"+fileName+"/r/n");
}
else if(event.getActionCommand().equals("save")){
//保存文件
dia.______;
dia.setVisible(true);
File file=dia.getSelectedFile();
String fileName=file.getAbsolutePath();
textArea.append("path of saved file:"+fileName+"/r/n");
}
}
public static void main(String args[]){
swingExample3 example=new swingExample3();
example.initGUI();
}
}
问答题通过参数定制Applet，请在画线处填写适当的语句，使程序能正确运行。
(1)para_duke.html
＜HTML＞
＜HEAD＞＜TITLE＞A Simple Program＜TITLE＞＜/HEAD＞
＜BODY＞
＜applet code="DrawAny.class" width="100" height="100" align="bottom"＞
＜param name="image" value="duke.gif"＞
＜/applet＞
＜/BODY＞
＜/HTML＞
(2)DrawAny.java
imporrt java.awt.*;
import java.applet.*;
import java.net.URL；
public class DrawAny extends Applet{
Image im;
public void init(){
URL url=getDocumentBase();
String imageName=getParameter("image");
______
}
public void paint(Graphics g){
g.drawImage(0,0,this);
}
}
问答题本题分别比较两个字符串”A”和”a”是否相等，并比较两个字符”A”和”a”是否相等，并输出比较结果。
问答题以下程序是一个简单文本处理器，菜单项可以打开、编辑、保存一个文件。文件内容显示在下面的文本区域中(提示，打开文件通过文件选择器来完成)。请改正程序中的错误(有下划线的语句)，使程序能输出正确的结果。运行结果如下图所示。注意：不改动程序的结构，不得增行或删行。importjava.awt.*;importjava.awt.event.*;importjava.io.*;importjavax.swing.*;classFileFrameextendsJFrameFilefile;JTextPanetextpane;FileInputStreamreadStream;JScrollPanescroll;publicFileFrame()super("文件浏览");JMenufileM=newJMenu("文件");OpenActionopen=newOpenAction();SaveActionclear=newSaveAction();ExitActionexit=newExitAction();JMenuBarmb=newJMenuBar();fileM.add(open);fileM.add(clear);fileM.add(exit);mb.add(fileM);textpane=newJTextPane();scroll=newJScrollPane(textpane);getContentPane().add(scroll);getContentPane().addJMenuBar(mb);classOpenActionextendsAbstractActionpublicOpenAction()super("打开");publicvoidactionPerformed(ActionEvente)JFileChooserchooser=newJFileChooser();intstate=chooser.showOpenDialog(null);file=chooser.selectedFile();if(file!=nulltextpane.read(readStream,this);readStream.close();catch(IOExceptionioE)classSaveActionextendsAbstractActionpublicSaveAction()super("保存");publicvoidactionPerformed(ActionEvente)if(file==null)return;tryFileWriterout=newFileWriter(file);out.read(textpane.getText());out.close();catch(IOExceptionioE)classExitActionextendsAbstractActionpublicExitAction()super("退出");publicvoidactionPerformed(ActionEvente)System.exit(0);publicstaticvoidmain(Stringargv[])FileFramef=newFileFrame();f.setDefaultCloseOperation(JFrame.EXITONCLOSE);f.setSize(300,400);f.show();
问答题本程序中的窗口有一个按钮“得到最新日期”和三个文本框：“年”、“月”和“日”，单击“得到最新日期”按钮后，对应的文本框显示当前的年、月、日信息，如图所示。importjava.awt.*;importjava.awt.event.*;importjavax.swing.*;importjava.util.Date;publicclassexam_25extendsFrame{publicstaticvoidmain(Stringargs[]){exam_25f=newexam_25("exam_7");Panelpan=newPanel();f.init();}publicexam_25(Stringstr){super(str);}publicvoidinit(){addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});setSize(200,200);setLayout(newFlowLayout());nl=newJLabel("年");yl=newJLabel("月");rl=newJLabel("日");nj=newJTextField(10);yj=newJTextField(10);rj=newJTextField(10);jb=newJButton("得到最新日期");add(nj);add(nl);add(yj);add(yl);add(rj);add(rl);add(jb);jb.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){da=______;nj.setText((newInteger(da.getYear()+1900)).toString());yj.setText((newInteger(da.getMonth()+1)).toString());rj.setText((newInteger(______)).toString());}});setVisible(true);}privateJLabelnl;privateJLabelyl;privateJLabelrl;privateJTextFieldnj;privateJTextFieldyj;privateJTextFieldrj;privateJButtonjb;privateDateda;}
问答题本程序的功能是读取命令行中参数的个数，并依次输出打印，如果没有输出参数，则打印输出“No para”。例如运行程序：java exam_41 par1 par2，则打印输出：Para 0:par1 Para1:par2。
public class exam_41{
public static void main(______args){
int num;
______;
if(num==0)
System.out.println("No para!");
for(int i=0; ______){
System.out.println("Para"+i+":"+args[i]);
}
}
}
问答题本程序的功能是读取用户输入的整数a、b，单击按钮“计算”，则计算出a和b数的和，并显示计算的结果。请将程序补充完整。 注意：请勿修改main()主方法和其他已有语句内容，仅在横线处填入适当语句。 import java.awt.*; import java.awt.event.*; import javax.swing.*; public class simple public static void mainString[] args) ExampleFrame frame=new ExampleFrame(); frame.______(JFrame.EXIT_ON_CLOSE); frame.show(); class ExampleFrame extends JFrame private JPanel panel; public static final int DEFAULT_WIDTH=250; public static final int DEFAULT_HEIGHT=250; public ExampleFrame() Init(); setTitle("welcome"); setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT); Container contentPane=getContentPane(); contentPane.add(panel); private void init() JLabel la1=new JLabel("输入整数a:"); JLabel la2=new JLabel ("输入整数b:"); final JTextField num1=new JTextField(10); final JTextField num2=new JTextField(10); JButton but=new JButton("计算"); final JLabel res=new JLabel("结果:"); but.addActionListener(______ public void actionPerformed(ActionEvent event) String str=new String(); String s1=num1.getText(); String s2=num2.getText(); try int a=Integer.parseInt(s1); int b=Integer.parseInt(s2); str=String.valueOf(a +b); catch(Exception e) str=e.getMessage(); res.setText ("结果:"+str); ); panel=new JPanel(); panel.setLayout(new FlowLayout(FlowLayout.LEFT)); panel.add(la1); panel.add(num1); panel.add(la2); panel.add(hum2); panel.add(but); panel.add(res);
问答题下面是一个Applet程序，程序的功能是用鼠标点击画图。本题是通过点击鼠标后画出一个“Java”字。请改正程序中的错误(有下划线的语句)，使程序能输出正确的结果。
注意：不改动程序的结构，不得增行或减行。
import java. awt.*
import java. awt. event.*;
import java. applet.*
/*
＜applet code= SimpleHitMouse. java width= 800 height= 400＞
＜/applet＞
*/
public class SimpleHitMouse {{U}}implements{{/U}} Applet{
private java. util. Vector points= new java. util. Vector();
public void init() {
addMouseListener(new MouseAdapter () {
public void mousePressed(MouseEvent e) (
points, add (new Point (e. getX( ), e. getY ( ) ) );
{{U}}paint( ){{/U}};
}
});
}
public void update(Graphics g) {
{{U}}repaint(g){{/U}};
}
public void paint(Graphics g) {
for(int i=0;i＜points, size() ;i++) {
Point dot= (Point)points. elementAt(i);
g. drawString("x" ,dot. x,dot, y),
}
}
public static void main(String args[]) {
Frame fram=new Frame("CelayTree");
SimpleHitMouse dot=new SimpleHitMouse();
dot. init( );
dot. start();
fram. add( "Center", dot)
fram. setSize(400,300);
fram. addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e)
{System. exit(0);}
})；
fram.show()
}
}
exl_2.html:
＜html＞
＜head＞
＜title＞A Simple program＜/title＞
＜/head＞
＜body＞
＜applet code="SimpleHitMouse, class" width=800 height=400＞
＜/applet＞
＜/body＞
＜/html＞