问答题本题程序的功能是监听键盘敲击事件，并将敲击的字符显示在标签上。开始时文字标签提示“Please press your keyboard!”，当按下键盘上的字符键时，文字标签就变为“'X'is pressed!”(X代表用户按下的键所代表的字符)。请将下述程序补充完整(注意：不得改动程序的结构，不得增行或删行)。 import java.awt.*; import java.awt.event.*; import javax.swing.*; public class simple extends Frame ______ public static void main(String args[]) simple f = new simple("simple"); Panel pan = new Panel(); f.init(); public simple(String str) super (str); public void init() addWindowListener(new WindowAdapter() public void windowClosing(WindowEvent e) System.exit (0); ); setSize(200,200); setLayout(new FlowLayout()); lab = new Label("Please press your keyboard!"); add(lab); addKeyListener(this); setVisible(true); public void keyTyped(KeyEvent e) lab.setText("/'"+______+"/' is pressed!"); repaint(); public void keyPressed(KeyEvent e) public void keyReleased(KeyEvent e) private Label lab;
问答题请完成下列Java程序。实例listener是监听器，frm是事件源，fr上发生的事件委托tat进行处理。程序的执行结果是显示一个蓝色的窗口，单击关闭按钮，可关闭窗口。注意：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。importjava．awt．*；importjava．awt．event．*；publicclassBlueWindow{publicstaticvoidmain(Stringargs[]){Framefrm=newFrame("欢迎参加Java考试!")；TheAdapterTestlistener=newTheAdapterTest()；frm．_____________________frm．setSize(200，200)；frm．setBackground(Color．blue)；frm.____________________}}classTheAdapterTestextendsWindowAdapter{publicvoidwindowClosing(WindowEvente){System.exit(1);}}
问答题本程序比较两个数组arr1={2,4,6,8,10}和arr2={3,5,7,9,11,13,15,17}的长度，然后用长度短的数组覆盖长度长的数组的前几项，再将覆盖后的数组中的元素打印出来。
public class exam_16{
public static void main(String[] args){
int [] arr1={2,4,6,8,10};
int [] arr2={3,5,7,9,11,13,15,17};
if(______){
______;
for(int i=0; i＜arr2.length; i++)
System.out.print(arr2[i]+" ");
}
else{
______;
for(int i=0; i＜arr2.length; i++)
System.out.print(arr2[i]+" ");
}
}
}
问答题下面是一个Applet程序，其功能是建立两个文本区域，一个为编辑区，一个为只读区；建立两个按钮，一个实现将编辑区中被鼠标选定的文本内容复制到只读区中，一个实现将只读区的全部文本内容清空。请更正题中带下划线的部分。 注意：不改变程序的结构，不得增行或删行。 import java.awt.*; import java.applet.*; /* ＜applet code="exl4_3.class" width=800 height=400＞ ＜/applet＞ */ public class exl4_3 extends Applet private Button okBtn, clearBtn; private String strMessage; private TextArea tArea1, tArea2; public void init() strMessage="Hello! Welcome to the test! /n" +"Wish you good luck!"; tArea1=new TextArea(10,25); tArea1.setText(strMessage); tArea2=new TextArea(10,25); tArea2.setEditable(true); okBtn=new Button("Copy"); clearBtn=new Button("Clear"); add(tArea1); add(tArea2); add(okBtn); add(clearBtn); public boolean action(Event e,Object o) if(e.target= =okBtn) tArea1.setText(tArea2.getSelectedText()); else if(e.target= =clearBtn) tArea1.setText(""); return ture; exl4_3.html ＜HTML＞ ＜HEAD＞ ＜TITLE＞exl4_3＜/TITLE＞ ＜/HEAD＞ ＜BODY＞ ＜applet code="exl4_3.class"width=800 height=400＞ ＜/applet＞ ＜/BODY＞ ＜/HTML＞
问答题本程序的功能是监听对于列表项的选择和复制。窗口中有两个列表和一个“Copy”按钮，在左侧列表中选中一个或多个列表项后，单击“Copy”按钮后，选中项就设置为右侧列表中的项，如图所示。importjavax.swing.*;importjava.awt.*;importjava.awt.event.*;publicclassexam_69extendsJFrameimplementsListSelectionListener{privateJListcolorList,copyList;privateJButtoncopy;privateStringcolorNames[]={"Black","Blue","Cyan","DarkGray","Gray","Green","LightGray","Magenta","Orange","Pink","Red","White","Yellow"};publicexam_69(){super("exam_69");Containerc=getContentPane();c.setLayout(newFlowLayout());colorList=newJList(colorNames);colorList.setVisibleRowCount(5);colorList.setFixedCellHeight(15);colorList.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);c.add(newJScrollPane());copy=newJButton("Copy＞＞＞");copy.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){copyList.setListData(getSelectedValues());}});c.add(copy);copyList=newJList();copyList.setVisibleRowCount(5);copyList.setFixedCellWidth(100);copyList.setFixedCellHeight(15);copyList.setSelectionMode(ListSelectionModeI.SINGLE_INTERVAL_SELECTION);c.add(newJScrollPane(copyList));setSize(300,120);show();}publicstaticvoidmain(Stringargs[]){exam_69app=newexam_69();app.addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});}}
问答题System.out.println(a[i]+ "" );
问答题本程序利用递归方法求前n个自然数的和(n=10)。
public class exam_61{
public static void main(String[] args) {
int sum=add(10);
System.out.println("1+2+…+9+10="+sum);
}
public static int add(______){
if(n==1){
______;
}
else
______;
}
}
问答题本程序的功能是使用单选框按钮选择边框的显示风格，当选中某个风格按钮后，边框就会对应更新为选中的风格，边框风格分别有：凹斜角、凸斜角、凹槽、线型和宽边型，如图所示。importjava.awt.*;importjava.awt.event.*;importjavax.swing.*;importjavax.swing.border.*;classBorderFrameextendsJFrameimplementsActionListener{publicBorderFrame(){JPanelbuttonPanel=newJPanel();group=newButtonGroup();addRadioButton(buttonPanel,group,"Loweredbevel",true);addRadioButton(buttonPanel,group,"Raisedbevel",false);addRadioButton(buttonPanel,group,"Etched",false);addRadioButton(buttonPanel,group,"Line",false);addRadioButton(buttonPanel,group,"Matte",false);addRadioButton(buttonPanel,group,"Empty",false);Borderetched=BorderFactory.createEtchedBorder();Bordertitled=BorderFactory.createTitledBorder(etched,"Bordertypes");buttonPanel.setBorder(titled);getContentPane().add(buttonPanel,"South");setDemoPanel();setTitle("exam_9");setSize(600,200);addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});}publicvoidaddRadioButton(JPanelbuttonPanel,ButtonGroupg,StringbuttonName,booleanv){JRadioButtonbutton=newJRadioButton(buttonName,v);button.addActionListener(______);g.add(button);buttonPanel.add(button);button.setActionCommand(buttonName);}publicvoidactionPerformed(ActionEventevt){______;}publicvoidsetDemoPanel(){JPanelpanel=newJPanel();Borderborder=null;Stringcommand=group.getSelection().getActionCommand();if(command.equals("Loweredbevel"))border=BorderFactory.createLoweredBevelBorder();elseif(command.equals("Raisedbevel"))border=BorderFactory.createRaisedBevelBorder();elseif(command.equals("Etched"))border=BorderFactory.createEtchedBorder();elseif(command.equals("Line"))border=BorderFactory.createLineBorder(Color.blue);elseif(command.equals("Matte"))border=BorderFactory.createMatteBorder(10,10,10,10,Color.blue);elseif(command.equals("Empty"))border=BorderFactory.createEmptyBorder();panel.setBorder(border);getContentPane().add(panel,"Center");validate();}privateJPanelpanel;privateButtonGroupgroup;}publicclassexam_9{publicstaticvoidmain(String[]args){JFrameframe=newBorderFrame();frame.show();}}
问答题综合应用题下面是一个Applet程序，其功能是通过两个文本框获得用户输入两个数，按回车键计算这两个数的商。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，不得增行或删行。程序运行结果如下图：importjava.awt.*;importjava.awt.Event.*;importjava.applet.*;/**/publicclassex14_3extendsApplet{privateTextFieldtf1,tf2;privateStringstrAnswer;publicvoidinit(){tf1=newTextField(20);add(tf1);tf2=newTextField(20);add(tf2);strAnswer="Undefined";}publicvoidpaint(Graphicsg){Fontf=newFont("TimesRoman",Font.PLAIN,20);g.setFont(f);g.drawString("result:",80,100);g.drawString(strAnswer,60,150);}publicbooleanaction(Evente,Objecto){Strings1=tf1.getText();Strings2=tf2.getText();try{intn1=String.valueOf(s1);intn2=String.valueOf(s2);intout=n1/n2;strAnswer=Integer.parseInt(out);}catch(NumberFormatExceptionnfe){strAnswer="errornumber!";}repaint();returntrue;}}ex14_3.htmlex14_3
问答题请在下面程序的画线处填上适当的代码：
import java.io.*;
public class SerialCloneTest{
public static void main(String[]args){
Employee harry=new Employee("李明");
Employee harry2=(Employee)harry.clone();
System.out.println(harry+"Copy:"+harry2+"2");
}
}
class SerialCloneable implements Cloneable,Serializable{
public Object clone(){
try{______}catch(Exception e){
return null;
}
}
}
class Employee extends SerialCloneable{
public Employee(String n){name=n;}
public String toString(){return name;}
private String name;
}
问答题下面是一个Applet程序，其功能是从3～100之间(包括3和100)每隔0.5秒显示一个新的数字，如果数字为素数，则显示为灰色，其他为绿色。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，不得增行或删行。
源程序文件代码清单如下：
import java.awt.*;
import java.applet.Applet;
/*
＜applet code=ex15_3.class width=800 height=400＞
＜/applet＞
*/
public class ex15_3 extends Applet
{
public Color color15_3 = Color.black;
private int n15_3 = 3;
public myPrime thPrime15_3;
public void init()
{
thPrime15_3 = new myPrime(this);
thPrime15_3.start();
}
public void paint(Graphics g)
{
g.setColor(color15_3);
g.
drawString(n15_3, 50, 50)
;
}
public int getInt()
{
return n15_3;
}
public void setInt(int i)
{
n15_3=i;
}
}
class myPrime extends Thread
{
ex15_3 obj15_3;
myPrime (ex15_3 o)
{
this.obj15_3 = o;
}
public boolean isPrime(int n)
{
boolean bPrime = true;
int i=2;
if(n＜3||n＞100)
return false;
while(i＜n-1
i++;
}
return bPrime;
}
public void run()
{
int i;
for (i=3;
i＜100
; i++)
{
if (isPrime(i))
obj15_3.color15_3 = Color.gray;
else
obj15_3.color15_3 = Color.green;
obj15_3.n15_3;
obj15_3.repaint();
try{
sleep(500);
}catch (InterruptedException ie)
____
}
}
}
ex15_3.html
＜HTML＞
＜HEAD＞
＜TITLE＞ex15_3＜/TITLE＞
＜/HEAD＞
＜BODY＞
＜applet code="ex15_3.class" width=800 height=400＞
＜/applet＞
＜/BODY＞
＜/HTML＞
问答题简单应用题请完成下列Java程序：创建一个具有2行3列的GridLayout管理器，包括Choice,Label,Button构件，布局为第1行包括一个Choice构件（包括2个选项item1和item2），一个Label构件（当选择Choice构件中的选项时，Label构件显示相应的名称，即，如果点击item1则Label中显示item1），和一个exit按钮（点击则退出应用程序），第2行包括3个Button构件。程序运行结果如下：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。importjava.awt.*;importjava.awt.event.*;publicclassex1_2extendsFrameimplementsActionListener,ItemListener{privateLabell;privateStringstr="label";privateChoicechoice1_2;publicstaticvoidmain(String[]arg){newex1_2();}ex1_2(){setLayout();choice1_2=newChoice();choice1_2.addItem("item1");choice1_2.addItem("item2");choice1_2.;add(choice1_2);l=newLabel(str);add(l);Buttonexit1_2=newButton("exit");exit1_2.addActionListener(this);add(exit1_2);for(inti=0;i<3;i++)add(newButton("button"+i));setSize(300,300);pack();show();}publicvoidactionPerformed(ActionEventevent){if(event.getActionCommand().equals("exit")){System.exit(0);}}publicvoiditemStateChanged(ItemEventevent){str=choice1_2.getSelectedItem();l.setText(str);}}
问答题本题定义了一个方法add()，用于求两个整形数的和。方法中有两个整形参数a和b，方法体中计算a和b的和sum，并将结果返回。程序中调用add()方法求整数24和34的和，并将结果打印输出。
public class javal{
public static void main(String[] args) {
int a=24,b=34;
System.out.println(add(a,b));
}
public static int add(______){
______;
sum=a+b;
______;
}
}
问答题下面是一个Applet程序，其功能是输入3个双精度浮点数：a，b，c，构成一个一元二次方程，a*x*x+b*x+c=0，其判别式d=b*b-4*a*c，若d为负数则输出“没有实根”，否则打印出2个实根。要求，有3个输入框，输入a，b，c，一个按钮，点击实现求根过程，一个不可编辑的文本区，用作输出结果。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，不得增行或删行。程序运行结果如下：importjava.io.*;importjava.awt.*;importjava.awt.event.*;import.java.applet.Applet;/*＜appletcode="ex21_3.class"width=800height=400＞＜/applet＞*/publicclassex21_3extendsAppletimplementsActionListener{Panelpane=newPanel();Label11=newLabel("a:");TextFieldtf1=newTextField(5);Label12=newLabel("b:");TextFieldtf2=newTextField(5);Label13=newLabel("c:");TextFieldtf3=newTextField(5);Buttonbtn=newButton("OK");Label14=newLabel("答案:");TextFieldtf4=newTextField(20);ex21_3obj21_3;publicvoidinit(){pane.setLayout(newFlowLayout(FlowLayout.LEFT,10,5));pane.add(11);pane.add(tf1);pane.add(12);pane.add(tf2);add("North",pane);Panelp2=newPanel();p2.setLayout(newFlowLayout(FlowLayout.LEFT,10,5));p2.add(13);p2.add(tf3);p2.add(btn);btn.addActionListener(this);add("Center",p2);Panelp3=newPanel();p3.setLayout(newFlowLayout(FlowLayout.LEFT,10,5));p3.add(14);tf4.setEditable(false);p3.add(tf4);add("South",p3);obj21_3=newex21_3();}publicvoiddoReal(doublea1,doublea2,doublea3,TextFieldtf){doubled,x1,x2;{{U}}d=a1*a1-4.0*a2*a3{{/U}};if(d＞=0.0){x1=(-a2+Math.sqrt(d))/(2.0*a1);{{U}}x2=(-a2+Math.sqrt(d))/(2.0*a1);{{/U}}tf.setText("2个实根:x1="+x1+"/nx2="+x2);}else{tf.setText("没有实根!");}}publicvoidactionPerformed(ActionEventae){doublea,b,c;try{a=newDouble(tf1.getText()).doubleValue();b=newDouble(tf2.getText()).doubleValue();c=newDouble(tf3.getText()).doubleValue();{{U}}obj21_3.doReal(a,b,c,14){{/U}};}catch(NumberFormatExceptionnfe){tf4.setText("wrongnumber!");}}}{{B}}ex21_3.htm1{{/B}}＜HTML＞＜HEAD＞＜TITLE＞ex21_3＜/TITLE＞＜/HEAD＞＜BODY＞＜appletcode="ex21_3.class"width=800height=400＞＜/applet＞＜/BODY＞＜/HTML＞
问答题本程序的功能是监听对于颜色的复制和粘贴。程序窗口中，有一个颜色设置框和“复制”和“粘贴”两个按钮，在颜色设置框中设置颜色后，下面的预览面板将显示选中的颜色，单击“复制”按钮后，将设置的颜色复制到系统的剪贴板上，然后继续选择其他颜色，当单击“粘贴”按钮后预览面板的颜色将设置为刚才复制的颜色，如图所示。importjava.io.*;importjava.awt.*;importjava.awt.datatransfer.*;importjava.awt.event.*;importjava.awt.image.*;importjavax.swing.*;publicclassexam_33{publicstaticvoidmain(String[]args){JFrameframe=newSerialTransferFrame();frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.show();}}classSerialTransferFrameextendsJFrame{publicSerialTransferFrame(){setTitle("exam_33");ContainercontentPane=getContentPane();chooser=newJColorChooser();contentPane.add(chooser,BorderLayout.CENTER);JPanelpanel=newJPanel();JButtoncopyButton=newJButton("复制");panel.add(copyButton);copyButton.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEventevent){copy();}});JButtonpasteButton=newJButton("粘贴");panel.add(pasteButton);pasteButton.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEventevent){paste();}});contentPane.add(panel,BorderLayout.SOUTH);pack();}privatevoidcopy(){Clipboardclipboard=Toolkit.getDefaultToolkit().getSystemClipboard();intcolor=chooser.getColor();serialSelectionselection=newSerialSelection(color);clipboard.setContents(selection,null);}privatevoidpaste(){Clipboardclipboard=Toolkit.getDefaultToolkit().getSystemClipboard();Transferablecontents=clipboard.getContents(null);if(contents==null)return;try{DataFlavorflavor=newDataFlavor("application/x-java-serialized-object;class=java.awt.Color");if(contents.isDataFlavorSupported(flavor)){Colorcolor=(Color)contents.getTransferData(flavor);chooser.set(color);}}catch(ClassNotFoundExceptionexception){JOptionPane.showMessageDialog(this,exception);}catch(UnsupportedFlavorExceptionexception){JOptionPane.showMessageDialog(this,exception);}catch(IOExceptionexception){JOptionPane.showMessageDialog(this,exception);}}privateJColorChooserchooser;}classSerialSelectionimplementsTransferable{SerialSelection(Serializableo){obj=o;}publicDataFlavor[]getTransferDataFlavors(){DataFlavor[]flavors=newDataFlavor[2];Classtype=obj.getClass();StringmimeType="application/x-java-serialized-object;class="+type.getName();try{flavors[0]=newDataFlavor(mimeType);flavors[l]=DataFlavor.stringFlavor;returnflavors;}catch(ClassNotFoundExceptionexception){returnnewDataFlavor[0];}}publicbooleanisDataFlavorSupported(DataFlavorflavor){returnDataFlavor.stringFlavor.equals(flavor)||"application".equals(flavor.getPrimaryType())}publicvoidgetTransferData(DataFlavorflavor)throwsUnsupportedFlavorException{if(!isDataFlavorSupported(flavor))thrownewUnsupportedFlavorException(flavor);if(DataFlavor.stringFlavor.equals(flavor))returnobj.toString();returnobj;}privateSerializableobj;}
问答题下面的程序的功能是将数组array下标为奇数的元素相乘(数组的位置是从0开始的)，并将乘积存放到变量total中。请在程序的每条横线处填入适当的语句，使程序的功能完整。
注意：请勿改动main()主方法和其他已有的语句内容，仅在横线处填入适当的语句。
public class JiShuJi
{
public static void main(String args[ ])
{
int array[ ]={1,2,3,5,7,9};
long total= ________________________;
for(int i=1;i＜=__________________ i++)
{
____________________
i++;
}
System.out.println(total);
}
}
问答题本程序将整型变量op1的二进制第4位(从低位开始计算)数进行翻转(即如果是1，则变成0；如果是0，则变成1)。
public class exam_54{
public static void main(String[] args) {
______op1=21;
______op2=8;
______;
System.out.println(op1);
}
问答题下面是一个Applet程序，其功能是将完整的图像显示于Applet的区块中，然后可以通过拖动鼠标让图像随着鼠标拖动的轨迹而移动。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，不得增行或删行。程序运行结果如下：importjava.applet.*;importjava.awt.*;/*＜appletcode="ex8_3.class"width=800height=400＞＜/applet＞*/publicclassex8_3extendsAppletprivateImageiImg;privateintxPos,yPos;publicvoidinit()xPos=yPos=0;iImg=getImage("ex8_3.jpg");publicvoidpaint(Graphicsg)g.drawImage(iImg,xPos,yPos);publicbooleanmouseDrag(Evente,intx,inty)xPos=x;yPos=y;paint();returntrue;ex8_3.htm＜HTML＞＜HEAD＞＜TITLE＞ex8_3＜/TITLE＞＜/HEAD＞＜BODY＞＜appletcode="ex8_3.class"width=800height=400＞＜/applet＞＜/BODY＞＜/HTML＞
问答题本程序中定义了一个树型的通讯录，窗口左侧是一个树，右侧是一个文本域，单击树节点，则在右侧文本域中显示相关信息，如果单击的是子节点，则显示对应名字的电话信息，如图所示。importjavax,swing.*;importjavax.swing.tree.*;importjava.awt.*;importjava.awt.event.*;importjavax,swing,event.*;classMytree2extendsJFrame______{JTreetree=null;JTextAreatext=newJTextArea(20,20);Mytree2(){Containercon=getContentPane();DefaultMutableTreeNoderoot=newDefaultMutableTreeNode("同学通迅录");DefaultMutableTreeNodet1=newDefaultMutableTreeNode("大学同学");DefaultMutableTreeNodet2=newDefaultMutableTreeNode("研究生同学");DefaultMutableTreeNodet11=newDefaultMutableTreeNode("陈艳");DefaultMutableTreeNodet12=newDefaultMutableTreeNode("李小永");DefaultMutableTreeNodet21=newDefaultMutableTreeNode("王小小");DefaultMutableTreeNodet22=newDefaultMutableTreeNode("董小");root.add(t1);root.add(t2);t1.add(t1_1);t1.add(t1_2);t2.add(t2_1);t2.add(t2_2);tree=newJTree(root);JScrollPanescrollpane=newJScrollPane(text);JSplitPanesplitpane=newJSplitPane(JSplitPane.HORIZONTALSPLIT,true,tree,scrollpane);tree.addTreeSelectionListener(this);con.add(splitpane);addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){System.exit(0);}});setVisible(true);setBounds(70,80,200,300);}publicvoidvalueChanged(TreeSelectionEvente){if(e.getSource()==tree){DefaultMutableTreeNodenode=(DefaultMutableTreeNode)tree.getLastSelectedPathComponent();if(node.isLeaf()){Stringstr=______;if(str.equals("陈艳")){text.setText(str+":联系电话:0411-4209876");}elseif(str.equals("李小永")){text.setText(str+":联系电话:010-62789876");}elseif(str.equals("王小小")){text.setText(str+":联系电话:0430-63596677");}elseif(str.equals("董小")){text.setText(str+":联系电话:020-85192789");}}else{text.setText(node.getUserObject().toString());}}}}publicclassexam_100{publicstaticvoidmain(Stringargs[]){Mytree2win=newMytree2();win.pack();}}
问答题本题程序的功能是使用GridBayLayout来组织窗口上的按钮。窗口中共有7个按钮，前3个按钮放置在第1排，第4个按钮独占第2排，第6个按钮位于第3排的右侧，而第5和第7个按钮共同处于第3排的左侧。请将下述程序补充完整(注意：不得改动程序的结构，不得增行或删行)。 import javax.swing.*; import java.awt.*; import java.awt.event.*; public class simple extends Jframe private JPanel jpanel1=new JPanel(); private GridLayout g1; private JButton JButton1 = new JButton("第一个"); private JButton JButton2 = new JButton("第二个"); private JButton JButton3 = new JButton("第三个"); private JButton JButton4 = new JButton("第四个"); private JButton JButton5 = new JButton("第五个"); private JButton JButton6 = new JButton("第六个"); private JButton JButton7 = new JButton("第七个"); public ______() super("simple"); setSize(300,150); GridBagLayout gbl= ______; jpanell.setLayout(gbl); GridBagConstraints gbc = new GridBagConstraints(); gbc.fill = GridBagConstraints.BOTH; gbc.gridwidth = 1; gbc.gridheight = 1; gbc.gridx = 0; gbc.gridy = 0; jpanell.add(JButtonl,gbc); gbc.gridx = 1; jpanell.add(JButton2,gbc); gbc.gridx = 2; jpanell.add(JButton3,gbc); gbc.gridx = 0; gbc.gridy = 1; gbc.gridwidth = 3; jpanell.add(JButton4,gbc); gbc.gridy = 2; gbc.gridwidth = 1; jpanell.add(JButton5,gbc); gbc.gridx = 1; gbc.gridwidth = 2; gbc.gridheight = 2; jpanell.add(JButton6,gbc); gbc.gridx = 0; gbc.gridy = 3; gbc.gridwidth = 1; gbc.gridheight = 1; jpanell.add(JButton7,gbc); this.setContentPane (jpanel1); public static void main (String args[]) simple fgl= new simple(); fgl.show(); fgl.addWindowListener(new WindowAdapter() public void windowClosing(WindowEvent e) System.exit(0); );