Java SE实验项目3 组件与事件编程(1)(2)

for(int i=星期几,n=1;i<星期几+day;i++) {

a[i]=String.valueOf(n) ; n++; } return a; } }

//CalendarFrame.java

import java.util.*; import java.awt.*; import java.awt.event.*; import java.applet.*;

public class CalendarFrame extends Frame implements ActionListener { Label labelDay[]=new Label[42]; Button titleName[]=new Button[7];

String name[]={\日\一\二\三\四\五\六\ Button nextMonth,previousMonth; int year=2006,month=10; CalendarBean calendar;

Label showMessage=new Label(\ public CalendarFrame() { Panel pCenter=new Panel();

【代码1】 //将pCenter的布局设置为7行7列的GridLayout 布局。 for(int i=0;i<7;i++)

{ titleName[i]=new Button(name[i]);

【代码2】//pCenter添加组件titleName[i]。 }

for(int i=0;i<42;i++) {

labelDay[i]=new Label(\ 【代码3】//pCenter添加组件labelDay[i]。 }

calendar=new CalendarBean(); calendar.setYear(year); calendar.setMonth(month); String day[]=calendar.getCalendar(); for(int i=0;i<42;i++)

{ labelDay[i].setText(day[i]); }

nextMonth=new Button(\下月\ previousMonth=new Button(\上月\ nextMonth.addActionListener(this); previousMonth.addActionListener(this);

Panel pNorth=new Panel(), pSouth=new Panel(); pNorth.add(previousMonth); pNorth.add(nextMonth); pSouth.add(showMessage);

showMessage.setText(\日历：\年\月\ ScrollPane scrollPane=new ScrollPane(); scrollPane.add(pCenter);

【代码4】// 窗口添加scrollPane在中心区域 【代码5】// 窗口添加pNorth 在北面区域 【代码6】// 窗口添加pSouth 在南区域。 }

public void actionPerformed(ActionEvent e) { if(e.getSource()==nextMonth) { month=month+1; if(month>12) month=1;

calendar.setMonth(month); String day[]=calendar.getCalendar(); for(int i=0;i<42;i++) { labelDay[i].setText(day[i]); } }

else if(e.getSource()==previousMonth) { month=month-1; if(month<1) month=12;

calendar.setMonth(month); String day[]=calendar.getCalendar(); for(int i=0;i<42;i++)

{ labelDay[i].setText(day[i]); } }

showMessage.setText(\日历：\年\月\ } }

//CalendarMainClass.java

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

{ CalendarFrame frame=new CalendarFrame(); frame.setBounds(100,100,360,300); frame.setVisible(true);

frame.validate();

frame.addWindowListener(new java.awt.event.WindowAdapter()

{ public void windowClosing(java.awt.event.WindowEvent e) { System.exit(0); } } ); } }

4、方程求根：请读懂下面模板程序，将其补充完整并调试运行。 //SquareEquation.java

public class SquareEquation { double a,b,c; double root1,root2; public void setA(double a) { this.a=a; }

public void setB(double b) { this.b=b; }

public void setC(double c) { this.c=c; }

public double getRootOne() throws NoRealRootException,NoSquareEquationException { if(a!=0)

{ double disk=b*b-4*a*c; if(disk>=0)

{ root1=(-b+Math.sqrt(disk))/(2*a); } else

{ throw new NoRealRootException(\没有实根\ } } else {

throw new NoRealRootException(\不是二次方程\ }

return root1; }

public double getRootTwo() throws NoRealRootException,NoSquareEquationException { if(a!=0)

{ double disk=b*b-4*a*c; if(disk>=0)

{ root2=(-b-Math.sqrt(disk))/(2*a);

} else

{ throw new NoRealRootException(\没有实根\ } } else {

throw new NoRealRootException(\不是二次方程\ }

return root2; } }

class NoRealRootException extends Exception { String message;

NoRealRootException(String s) { message=s; }

public String getMessage() { return message; } }

class NoSquareEquationException extends Exception { String message;

NoSquareEquationException(String s) { message=s; }

public String getMessage() { return message; } }

//EquationFrame.java

import java.awt.*; import java.awt.event.*;

public class EquationFrame extends Frame implements ActionListener { SquareEquation equation; TextField textA,textB,textC; TextArea showRoots; Button controlButton; public EquationFrame()

{ equation=new SquareEquation(); textA=new TextField(8); textB=new TextField(8); textC=new TextField(8); showRoots=new TextArea();

controlButton=new Button(\确定\ Panel pNorth=new Panel();

pNorth.add(new Label(\二次项系数:\ pNorth.add(textA);

pNorth.add(new Label(\一次项系数:\ pNorth.add(textB);

pNorth.add(new Label(\常数项系数:\ pNorth.add(textC);

pNorth.add(controlButton);

【代码1】 //当前窗口作为controlButton的ActionEvent事件的监视器 add(pNorth,BorderLayout.NORTH); add(showRoots,BorderLayout.CENTER); setBounds(100,100,630,160); setVisible(true); validate();

addWindowListener(new WindowAdapter()

{ public void windowClosing(WindowEvent e) { System.exit(0); } } ); }

public void actionPerformed(ActionEvent e) { try{

double a=Double.parseDouble(【代码2】); //textA调用方法获取其中的文本

double b=Double.parseDouble(【代码3】); //textB调用方法获取其中的文本

double c=Double.parseDouble(【代码4】); // textC调用方法获取其中的文本

equation.setA(a); equation.setB(b); equation.setC(c); textA.setText(\ textB.setText(\ textC.setText(\

showRoots.append(\根：\ showRoots.append(\根：\ }

catch(Exception ex)

{ showRoots.append(\ } } }

//EquationMainClass.java

public class EquationMainClass

{ public static void main(String args[])

{ EquationFrame frame=new EquationFrame(); } }

思考：将下面题目改成运用Swing组件实现，观察有什么变化。