JAVA习题(3).doc

（1）package ch2;import org.eclipse.swt.layout.GridLayout;import org.eclipse.swt.graphics.Point;import org.eclipse.swt.widgets.MessageBox;import org.eclipse.swt.widgets.Shell;import org.eclipse.swt.widgets.Display;import org.eclipse.swt.widgets.Label;import org.eclipse.swt.SWT;import org.eclipse.swt.graphics.Rectangle;import org.eclipse.swt.graphics.Font;import org.eclipse.swt.widgets.Text;import org.eclipse.swt.widgets.Button;public class P32 private Shell sShell = null; / jve:decl-index=0:visual-constraint=20,9private Label label = null;private Text text = null;private Button button = null;/* * param args */public static void main(String args) / TODO 自动生成方法存根/* Before this is run, be sure to set up the launch configuration (Arguments-VM Arguments) * for the correct SWT library path in order to run with the SWT dlls. * The dlls are located in the SWT plugin jar. * For example, on Windows the Eclipse SWT 3.1 plugin jar is: * installation_directorypluginsorg.eclipse.swt.win32_3.1.0.jar */Display display = Display.getDefault();P32 thisClass = new P32();thisClass.createSShell();thisClass.sShell.open();while (!thisClass.sShell.isDisposed() if (!display.readAndDispatch()display.sleep();display.dispose();/* * This method initializes sShell */private void createSShell() sShell = new Shell();sShell.setText(Shell);sShell.setSize(new Point(300, 200);sShell.setLayout(null);label = new Label(sShell, SWT.NONE);label.setBounds(new Rectangle(2, 21, 134, 38);label.setFont(new Font(Display.getDefault(), u6977u4f53_GB2312, 12, SWT.NORMAL);label.setText(请输入一个年份数);text = new Text(sShell, SWT.BORDER);text.setBounds(new Rectangle(153, 23, 130, 39);button = new Button(sShell, SWT.NONE);button.setBounds(new Rectangle(99, 88, 66, 40);button.setText(确定);button.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) MessageBox box=new MessageBox(sShell,SWT.ICON_WARNING|SWT.OK);box.setText(java 课堂);String s=text.getText();int y=Integer.parseInt(s);Boolean b1=(y%4=0)&(y%100!=0),b2=(y%400=0);String str=(b1|b2)?是:不是;box.setMessage(s+年+str+闰年);box.open(););（2）package ch2;public class P34 extends P32 /* * param args */public static void main(String args) / TODO 自动生成方法存根char a1=十,a2=点,a3=进,a4=攻;char secret=8;a1=(char)(a1secret);a2=(char)(a2secret);a3=(char)(a3secret);a4=(char)(a4secret);System.out.println(密文：+a1+a2+a3+a4);a1=(char)(a1secret);a2=(char)(a2secret);a3=(char)(a3secret);a4=(char)(a4secret); System.out.println(原文：+a1+a2+a3+a4);（3）package ch2;import org.eclipse.swt.layout.GridLayout;import org.eclipse.swt.graphics.Point;import org.eclipse.swt.widgets.Shell;import org.eclipse.swt.widgets.Display;import org.eclipse.swt.widgets.Button;import org.eclipse.swt.SWT;import org.eclipse.swt.graphics.Rectangle;import org.eclipse.swt.widgets.MessageBox;public class P36 private Shell sShell = null;private Button button = null;private Button button1 = null;byte b=0x7f; short s=0x7fff; int i=0x7fffffff; long l=0x7fffffffffffffffL; char c=字; float f=3.4E38F; double d=1.797631E308; boolean B=true; String S=北京欢迎你;/* * param args */public static void main(String args) / TODO 自动生成方法存根/* Before this is run, be sure to set up the launch configuration (Arguments-VM Arguments) * for the correct SWT library path in order to run with the SWT dlls. * The dlls are located in the SWT plugin jar. * For example, on Windows the Eclipse SWT 3.1 plugin jar is: * installation_directorypluginsorg.eclipse.swt.win32_3.1.0.jar */Display display = Display.getDefault();P36 thisClass = new P36();thisClass.createSShell();thisClass.sShell.open();while (!thisClass.sShell.isDisposed() if (!display.readAndDispatch()display.sleep();display.dispose();/* * This method initializes sShell */private void createSShell() sShell = new Shell();sShell.setText(Shell);sShell.setSize(new Point(300, 200);sShell.setLayout(null);button = new Button(sShell, SWT.NONE);button.setText(变量);button.setSize(new Point(75, 25);button.setLocation(new Point(53, 99);button.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) MessageBox box=new MessageBox(sShell,SWT.ICON_WARNING|SWT.OK); box.setText(各种类型数据); String str=字符型变量 c=+c+n; str=str+布尔型变量 b=+b+n; str=str+字符串类对象 S=+S+nn; str=str+数值型数据的最大值 : n; str=str+字节型变量 b=+b+n; str=str+短整型变量 s=+s+n; str=str+整型变量 i=+i+n; str=str+长整型变量 l=+l+n; str=str+浮点型变量 f=+f+n; str=str+双精度变量 d=+d+n; box.setMessage(str); box.open(););button.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) );button1 = new Button(sShell, SWT.NONE);button1.setText(转换);button1.setSize(new Point(73, 28);button1.setLocation(new Point(154, 96);button1.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) MessageBox box=new MessageBox(sShell,SWT.ICON_WARNING|SWT.OK); String str=; str=str+双精度变量 d=+d+n; str=str+转换为浮点型 :+(float)d+n; str=str+转换为长整型 :+(long)d+n; str=str+转换为整型 :+(int)d+n; str=str+转换为短整型 :+(short)d+n; str=str+转换为字节型 :+(byte)d+n; box.setText(强制类型转换); box.setMessage(str); box.open(););（4）package ch2;import org.eclipse.swt.layout.GridLayout;import org.eclipse.swt.graphics.Point;import org.eclipse.swt.widgets.Shell;import org.eclipse.swt.widgets.Display;import org.eclipse.swt.widgets.Label;import org.eclipse.swt.SWT;import org.eclipse.swt.graphics.Rectangle;import org.eclipse.swt.widgets.Text;import org.eclipse.swt.widgets.Button;import org.eclipse.swt.widgets.MessageBox;public class P38 private Shell sShell = null;private Label label = null;private Text text = null;private Button button = null;private Button button1 = null; int a,b,c;/* * param args */public static void main(String args) / TODO 自动生成方法存根/* Before this is run, be sure to set up the launch configuration (Arguments-VM Arguments) * for the correct SWT library path in order to run with the SWT dlls. * The dlls are located in the SWT plugin jar. * For example, on Windows the Eclipse SWT 3.1 plugin jar is: * installation_directorypluginsorg.eclipse.swt.win32_3.1.0.jar */Display display = Display.getDefault();P38 thisClass = new P38();thisClass.createSShell();thisClass.sShell.open();while (!thisClass.sShell.isDisposed() if (!display.readAndDispatch()display.sleep();display.dispose();/* * This method initializes sShell */private void createSShell() sShell = new Shell();sShell.setText(Shell);sShell.setSize(new Point(300, 200);sShell.setLayout(null);label = new Label(sShell, SWT.NONE);label.setBounds(new Rectangle(35, 29, 67, 37);label.setText(准备答题);text = new Text(sShell, SWT.BORDER);text.setBounds(new Rectangle(136, 29, 126, 45);button = new Button(sShell, SWT.NONE);button.setBounds(new Rectangle(43, 106, 91, 44);button.setText(出题);button.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) String str=; a=(int)(Math.random()*90)+10; b=(int)(Math.random()*90)+10; str=Integer.toString(a)+Integer.toString(b)+=; label.setText(str); text.setText(); text.setFocus(););button1 = new Button(sShell, SWT.NONE);button1.setBounds(new Rectangle(146, 108, 96, 42);button1.setText(提交);button1.addSelectionListener(new org.eclipse.swt.events.SelectionAdapter() public void widgetSelected(org.eclipse.swt.events.SelectionEvent e) MessageBox box=new MessageBox(sShell,SWT.ICON_WARNING|SWT.OK);c=Integer.parseInt(text.getText();box.setText(加法练习);box.setMessage(c=a+b?恭喜你，答对了！:再想一想);box.open(););（5）package ch2;import org.eclipse.swt.layout.GridLayout;import org.eclipse.swt.graphics.Point;import org.eclipse.swt.widgets.MessageBox;import org.eclipse.swt.widgets.Shell;import org.eclipse.swt.widgets.Display;import org.eclipse.swt.widgets.Label;import org.eclipse.swt.SWT;import org.eclipse.swt.graphics.Rectangle;import org.eclipse.swt.widgets.Text;import org.eclipse.swt.widgets.Button;import org.eclipse.swt.widgets.MessageBox;public class P39 private Shell sShell = null;private Label label = null;private Text text = null;private Button button = null;/* * param args */public static void main(String args) / TODO 自动生成方法存根/* Before this is run, be sure to set up the launch configuration (Arguments-VM Arguments) * for the correct SWT library path in order to run with the SWT dlls. * The dlls are located in the SWT plugin jar. * For example, on Windows the Eclipse SWT 3.1 plugin jar is: * installation_directorypluginsorg.eclipse.swt.win32_3.1.0.jar */Display display = Display.getDefault();P39 thisClass = new P39();thisClass.createSShell();thisClass.sShell.open();while (!thisClass.sShell.isDisposed() if (!display.readAndDispatch()display.sleep();dis