日常生活中，人们需要对某些常见图形和几何体做计算面积，体积，周长等相关计算。设计一个形状计算器，完成此功能。通过对菜单的选择，可以对不同的形状进行计算。
1 作业中的接口与类
2 抽象类用于所有空间实现JPANE
package comprehensive;
import javax.swing.JPanel;
import javax.swing.JTextField;
public abstract class AbstractPanel extends JPanel {
private static final long serialVersionUID = 1L;
public abstract JTextField getInputTextField();
}
2 通用接口和抽象了
// 通用抽象类
package comprehensive;
public abstract class Shape {
public abstract double area();
}
//通用接口
package comprehensive;
public interface cal {
final double PI=3.14;
double perimeter();
}
3 圆形矩形三角形圆柱的JPANE及实现类
1)接口 及实现类
//圆形jpane
package comprehensive;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JLabel;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.text.DecimalFormat;
public class CirclePanel extends AbstractPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
private JTextField txtradius;
private JTextField txtpre;
private JTextField txtarea;
private JTextField input; //用于获取当前获得焦点的文本框
JButton btncal,btnclear;
/**
* 创建圆形计算面板.
*/
public CirclePanel() {
// 圆面板设为网格布局方式,屏蔽setSize方法设置的大小，使用setPreferredSize(new Dimension(200, 220))设置大小
setLayout(new GridLayout(4, 1, 0, 0));
//设置半径信息面板
JPanel panelradius = new JPanel();
add(panelradius);
JLabel lblradius = new JLabel("圆的半径是");
panelradius.add(lblradius);
txtradius = new JTextField();
txtradius.addFocusListener(new Handle());
panelradius.add(txtradius);
txtradius.setColumns(10);
//设置放置按钮的面板
JPanel panelbutton = new JPanel();
add(panelbutton);
btncal = new JButton("计算");
panelbutton.add(btncal);
btnclear = new JButton("清除");
panelbutton.add(btnclear);
JPanel panelper = new JPanel();
add(panelper);
//设置显示周长信息的面板
JLabel lblpre = new JLabel("圆的周长是");
panelper.add(lblpre);
txtpre = new JTextField();
panelper.add(txtpre);
txtpre.setColumns(10);
//设置显示面积信息的面板
JPanel panelarea = new JPanel();
add(panelarea);
JLabel lblarea = new JLabel("圆的面积是");
panelarea.add(lblarea);
txtarea = new JTextField();
panelarea.add(txtarea);
txtarea.setColumns(10);
//为“计算”按钮和“清除”按钮设置监听
btnclear.addActionListener(new ActionListener() {
//清除两个文本框中信息
@Override
public void actionPerformed(ActionEvent e) {
txtarea.setText("");
txtpre.setText("");
txtradius.setText("");
}
});
btncal.addActionListener(new ActionListener() {
//计算并显示在文本框中
@Override
public void actionPerformed(ActionEvent e) {
double r=Double.parseDouble(txtradius.getText());
Circle cir=new Circle(r);
double ar=cir.area();
String formatAr=new DecimalFormat(".##").format(ar);
double per=cir.perimeter();
String formatPer=new DecimalFormat(".##").format(per);
txtpre.setText(formatPer);
txtarea.setText(formatAr);
}
});
}
class Handle extends FocusAdapter{
public void focusGained(FocusEvent e) {
input=(JTextField) e.getSource(); //设置输入文本框为当前获取焦点的文本框
}
}
public JTextField getInputTextField(){
return input; //该方法在keyPanel中调用，用于设置接收输入的文本框
}
}
//圆形计算接类
package comprehensive;
public class Circle extends Shape implements cal{
private double radius;
public Circle(double radius) {
super();
this.radius = radius;
}
public double perimeter() {
return 2*Math.PI*radius;
}
public double area() {
return radius*radius*PI;
}
}
//Cyiner.java
package comprehensive;
public class Cyiner extends Shape implements cal {
private double radius;
private double height;
public Cyiner(double radius,double height) {
super();
this.radius = radius;
this.height = height;
}
public double perimeter() {
return PI * radius * radius * height;
}
public double area() {
double s1 = 2 * PI * radius * height;
double s2 = PI * radius * radius;
return s1 + s2;
}
}
//CyPanel.java
package comprehensive;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class CyPanel extends AbstractPanel {
private static final long serialVersionUID = 1L;
JTextField input;
private JTextField txt_radius;
private JTextField txt_height;
private JTextField txt_per;
private JTextField txt_area;
JButton button_calc,button_clear;
public CyPanel() {
setLayout(new GridLayout(5, 1));
Handle handle = new Handle();
JPanel p1 = new JPanel();
JLabel l1 = new JLabel("圆柱体的半径是");
txt_radius = new JTextField(8);
txt_radius.addFocusListener(handle);
p1.add(l1);
p1.add(txt_radius);
add(p1);
JPanel p2 = new JPanel();
JLabel l2 = new JLabel(" 圆柱体的高是 ");
txt_height = new JTextField(8);
txt_height.addFocusListener(handle);
p2.add(l2);
p2.add(txt_height);
add(p2);
JPanel p3 = new JPanel();
button_calc = new JButton("计算");
button_calc.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Cyiner cy = new Cyiner(Double.parseDouble(txt_radius.getText()),
Double.parseDouble(txt_height.getText()));
txt_area.setText("" + cy.area());
txt_per.setText("" + cy.perimeter());
}
});
button_clear = new JButton("清除");
button_clear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
txt_area.setText(null);
txt_height.setText(null);
txt_per.setText(null);
txt_radius.setText(null);
}
});
p3.add(button_calc);
p3.add(button_clear);
add(p3);
JPanel p4 = new JPanel();
JLabel l3 = new JLabel("圆柱体的体积是");
txt_per = new JTextField(10);
p4.add(l3);
p4.add(txt_per);
add(p4);
JPanel p5 = new JPanel();
JLabel l4 = new JLabel("圆柱体的面积是");
txt_area = new JTextField(10);
p5.add(l4);
p5.add(txt_area);
add(p5);
}
public JTextField getInputTextField() {
return input;
}
class Handle extends FocusAdapter{
public void focusGained(FocusEvent e) {
input=(JTextField) e.getSource(); //设置输入文本框为当前获取焦点的文本框
}
}
}
//Triangle.java
package comprehensive;
public class Triangle extends Shape implements cal{
private double a,b,c;
public Triangle(double x,double y,double z) {
super();
a = x;
b = y;
c = z;
}
public double perimeter() {
return a + b + c;
}
public double area() {
double p = perimeter() / 2;
double s = Math.sqrt(p * (p-a) * (p-b) * (p-c));
return s;
}
}
//TrianglePanel.java
package comprehensive;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class TrianglePanel extends AbstractPanel {
private static final long serialVersionUID = 1L;
private JTextField txt_a;
private JTextField txt_b;
private JTextField txt_c;
private JTextField txtpre;
private JTextField txtarea;
private JTextField input; //用于获取当前获得焦点的文本框
JButton btncal,btnclear;
public TrianglePanel() {
setLayout(new GridLayout(6, 1));
JPanel pan = new JPanel();
JLabel l1 = new JLabel("第一条边长是");
txt_a = new JTextField(8);
pan.add(l1);
pan.add(txt_a);
add(pan);
JPanel p2 = new JPanel();
JLabel l2 = new JLabel("第二条边长是");
txt_b = new JTextField(8);
p2.add(l2);
p2.add(txt_b);
add(p2);
JPanel p3 = new JPanel();
JLabel l3 = new JLabel("第三条边长是");
txt_c = new JTextField(8);
p3.add(l3);
p3.add(txt_c);
add(p3);
Handle handle = new Handle();
Handles handles = new Handles();
txt_a.addFocusListener(handle);
txt_b.addFocusListener(handle);
txt_c.addFocusListener(handle);
JPanel p4 = new JPanel();
btncal = new JButton("计算");
btnclear = new JButton("清除");
p4.add(btncal);
p4.add(btnclear);
add(p4);
btncal.addActionListener(handles);
btnclear.addActionListener(handles);
JPanel p5 = new JPanel();
JLabel l4 = new JLabel("三角形的周长是");
txtpre = new JTextField(10);
p5.add(l4);
p5.add(txtpre);
add(p5);
JPanel p6 = new JPanel();
JLabel l5 = new JLabel("三角形的面积是");
txtarea = new JTextField(10);
p6.add(l5);
p6.add(txtarea);
add(p6);
}
class Handle extends FocusAdapter{
public void focusGained(FocusEvent e) {
input=(JTextField) e.getSource(); //设置输入文本框为当前获取焦点的文本框
}
}
public JTextField getInputTextField(){
return input; //该方法在keyPanel中调用，用于设置接收输入的文本框
}
class Handles implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
if(arg0.getSource() == btncal) {
Triangle t = new Triangle(Double.parseDouble(txt_a.getText()),
Double.parseDouble(txt_b.getText()), Double.parseDouble(txt_c.getText()));
txtarea.setText("" + t.area());
txtpre.setText("" + t.perimeter());
}
if(arg0.getSource() == btnclear) {
txt_a.setText(null);
txt_b.setText(null);
txt_c.setText(null);
txtarea.setText(null);
txtpre.setText(null);
}
}
}
}
//Rect.java
package comprehensive;
public class Rect extends Shape implements cal{
private double len;
private double wedth;
public Rect(double len,double wedth) {
super();
this.len = len;
this.wedth = wedth;
}
public double perimeter() {
return len + wedth;
}
public double area() {
return len * wedth;
}
}
//RectPanel.java
package comprehensive;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JLabel;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
public class RectPanel extends AbstractPanel {
private static final long serialVersionUID = 1L;
private JTextField txtlength,txtwidth;
private JTextField txtpre;
private JTextField txtarea;
private JTextField input; //用于获取当前获得焦点的文本框
JButton btncal,btnclear;
/**
* 创建圆形计算面板.
*/
public RectPanel() {
// 圆面板设为网格布局方式,屏蔽setSize方法设置的大小，使用setPreferredSize(new Dimension(200, 220))设置大小
setLayout(new GridLayout(5, 1, 0, 0));
//设置长度信息面板
JPanel panellength = new JPanel();
add(panellength);
JLabel lbllength = new JLabel("矩形的长是");
panellength.add(lbllength);
txtlength = new JTextField();
txtlength.addFocusListener(new Handle());
panellength.add(txtlength);
txtlength.setColumns(10);
//设置宽度信息面板
JPanel panelwidth= new JPanel();
add(panelwidth);
JLabel lblwidth = new JLabel("矩形的宽是");
panelwidth.add(lblwidth);
txtwidth = new JTextField();
panelwidth.add(txtwidth);
txtwidth.addFocusListener(new Handle());
txtwidth.setColumns(10);
//设置放置按钮的面板
JPanel panelbutton = new JPanel();
add(panelbutton);
btncal = new JButton("计算");
panelbutton.add(btncal);
btncal.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
double a = Double.parseDouble(txtlength.getText());
double b = Double.parseDouble(txtwidth.getText());
Rect rect = new Rect(a, b);
txtpre.setText(""+rect.perimeter());
txtarea.setText(""+rect.area());
}
});
btnclear = new JButton("清除");
panelbutton.add(btnclear);
btnclear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
txtarea.setText(null);
txtlength.setText(null);
txtwidth.setText(null);
txtpre.setText(null);
}
});
JPanel panelper = new JPanel();
add(panelper);
//设置显示周长信息的面板
JLabel lblpre = new JLabel("矩形的周长是");
panelper.add(lblpre);
txtpre = new JTextField();
panelper.add(txtpre);
txtpre.setColumns(10);
//设置显示面积信息的面板
JPanel panelarea = new JPanel();
add(panelarea);
JLabel lblarea = new JLabel("矩形的面积是");
panelarea.add(lblarea);
txtarea = new JTextField();
panelarea.add(txtarea);
txtarea.setColumns(10);
}
class Handle extends FocusAdapter{
public void focusGained(FocusEvent e) {
input=(JTextField) e.getSource(); //设置输入文本框为当前获取焦点的文本框
}
}
public JTextField getInputTextField(){
return input; //该方法在keyPanel中调用，用于设置接收输入的文本框
}
}
//输入键盘
package comprehensive;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.Border;
public class KeyPanel extends JPanel {
private static final long serialVersionUID = 1L;
/**
* 创建输入键盘面板
*/
JButton[] keyButton=new JButton[12];
String[] num={"1","2","3","4","5","6","7","8","9","0",".","BackSpace"};
AbstractPanel selectedPanel; //表示当前选择的图形面板，键入数据要传递到当前选择的面板中
JTextField inputTextField;
public KeyPanel() {
setPreferredSize(new Dimension(350, 230));
setLayout(new GridLayout(4,3));
Border lb=BorderFactory.createLineBorder(Color.gray, 2);
setBorder(lb);
Handle handle=new Handle();
for(int i=0;i<12;i++){
keyButton[i]=new JButton(num[i]);
keyButton[i].setFont(new Font("Arial",Font.BOLD,15));
keyButton[i].setForeground(Color.BLACK);
keyButton[i].addActionListener(handle);
add(keyButton[i]);
}
}
class Handle implements ActionListener{
@Override
public void actionPerformed(ActionEvent e) {
JButton button=(JButton)e.getSource(); //获取事件源，看是哪个按钮被按下
inputTextField=selectedPanel.getInputTextField(); //从传递来的形状面板中获取当前得到焦点的文本框
inputNumber(inputTextField, button); //调用inputNumber方法，在该文本框中输入数据
}
}
public void setSelectedPanel(AbstractPanel selected){
selectedPanel = selected;
}
public void inputNumber(JTextField tf,JButton button){ //根据不同事件源在文本框中显示不同信息
String oldString=tf.getText(); //获取文本框中已有信息
if(oldString==null){
tf.setText(" ");
}
String subStr=oldString.substring(0, oldString.length()); //根据不同事件源的不同情况，设置不同的值
String newString=button.getText();
if(newString.equals("BackSpace")){
tf.setText(subStr);
}
else if(newString.equals(".")){
tf.setText(oldString+".");
}
else{
tf.setText(oldString+newString);
}
}
}
//主运行程序 采用网格布局管理方式
package comprehensive;
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JRadioButtonMenuItem;
public class CalculatorWindow extends JFrame {
private static final long serialVersionUID = 1L;
private KeyPanel keypanel;
private AbstractPanel cirPanel,rectPanel,trianPanel,cyPanel;
private CardLayout card;
//菜单选项需要进行事件处理
JMenuItem menuExit;
JRadioButtonMenuItem menuCircle, menuRect,menuTangle,menuCyinder;
JPanel panelWest; //根据选项显示面板
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
CalculatorWindow frame = new CalculatorWindow();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public CalculatorWindow() {
setTitle("图形计算器");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 590, 306);
Container con=getContentPane();
//con.setLayout(new GridLayout(1,2));
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
Handle handle=new Handle();
//添加“文件”菜单、菜单项及为菜单项添加监听
JMenu menuFile = new JMenu("文件");
menuBar.add(menuFile);
menuExit = new JMenuItem("退出");
menuExit.addActionListener(handle);
menuFile.add(menuExit);
//添加“计算”菜单、菜单项及为菜单项添加监听
JMenu menuCalcu = new JMenu("计算");
menuBar.add(menuCalcu);
ButtonGroup group = new ButtonGroup();
menuCircle = new JRadioButtonMenuItem("圆形");
menuCircle.addActionListener(handle);
menuCalcu.add(menuCircle);
menuRect = new JRadioButtonMenuItem("矩形");
menuRect.addActionListener(handle);
menuCalcu.add(menuRect);
menuTangle = new JRadioButtonMenuItem("三角形");
menuTangle.addActionListener(handle);
menuCalcu.add(menuTangle);
menuCyinder = new JRadioButtonMenuItem("圆柱体");
menuCyinder.addActionListener(handle);
menuCalcu.add(menuCyinder);
group.add(menuCyinder);
group.add(menuTangle);
group.add(menuRect);
group.add(menuCircle);
//主窗口左方面板为卡片布局方式，按需求显示形状面板
panelWest = new JPanel();
panelWest.setPreferredSize(new Dimension(220, 0));
panelWest.setSize(220, 280);
card = new CardLayout();
panelWest.setLayout(card);
//添加卡片面板，并为其取卡片名
cirPanel=new CirclePanel();
rectPanel=new RectPanel();
trianPanel = new TrianglePanel();
cyPanel = new CyPanel();
panelWest.add("0",cirPanel);
panelWest.add("1",rectPanel);
panelWest.add("2",trianPanel);
panelWest.add("3",cyPanel);
con.add(panelWest,BorderLayout.WEST);
//主窗口右侧面板中显示keyPanel，用于输入数字
JPanel panelEast = new JPanel();
panelEast.setPreferredSize(new Dimension(360, 0));
keypanel=new KeyPanel();
keypanel.setSelectedPanel(cirPanel); //设置启动时，显示的图形面板为cirPanel，通过参数传递给keypanel，用于接收输入
panelEast.add(keypanel);
con.add(panelEast,BorderLayout.EAST);
}
//ActionEvent事件处理，根据菜单选项，显示对应卡片
class Handle implements ActionListener{
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == menuExit){
System.exit(0);
}else if(e.getSource() == menuCircle){
card.show(panelWest, "0");
keypanel.setSelectedPanel(cirPanel);
}else if(e.getSource() == menuRect){
card.show(panelWest, "1");
keypanel.setSelectedPanel(rectPanel);
}else if(e.getSource() == menuTangle) {
card.show(panelWest, "2");
keypanel.setSelectedPanel(trianPanel);
}else if(e.getSource() == menuCyinder) {
card.show(panelWest, "3");
keypanel.setSelectedPanel(cyPanel);
}
}
}
}
运行结果
