java实现绘制矩形和椭圆并计算面积和周长.doc

/*本文件由开伟同学亲情提供请将以下代码复制到编译器中，此文档完全免费*/import java.awt.*; import java.awt.event.*; import javax.swing.*; public class PCJFrame extends JFrame implements ActionListener private JRadioButton radio_Rec,radio_Ell; private JButton button_paint; private JTextField text_perimeter,text_area; public JTextField text_length,text_width; public int l,w; private RectangleCanvas Rectangle; private EllipseCanvas Ellipse; public PCJFrame() super(绘制平面图形并计算周长和面积); this.setSize(600,300); this.setLocation(200,100); this.setBackground(Color.white); this.setDefaultCloseOperation(EXIT_ON_CLOSE); JPanel panel1=new JPanel(new FlowLayout(1); this.getContentPane().add(panel1,North); ButtonGroup bgroup=new ButtonGroup(); radio_Rec=new JRadioButton(矩形,true);panel1.add(radio_Rec); bgroup.add(radio_Rec); radio_Ell=new JRadioButton(椭圆,true); panel1.add(radio_Ell); bgroup.add(radio_Ell);panel1.add(new Label(长度/长轴); text_length=new JTextField(10); panel1.add(text_length); panel1.add(new Label(宽度/短轴); text_width=new JTextField(10); panel1.add(text_width);button_paint=new JButton(绘图);button_paint.addActionListener(this);panel1.add(button_paint); JPanel panel2=new JPanel(new FlowLayout(1); this.getContentPane().add(panel2,South); text_perimeter=new JTextField(20); panel2.add(new Label(周长); panel2.add(text_perimeter); text_area=new JTextField(20); panel2.add(new Label(面积); panel2.add(text_area); this.setVisible(true); public void actionPerformed(ActionEvent e) double length=Double.parseDouble(text_length.getText(); double width=Double.parseDouble(text_width.getText(); l=(int)length; w=(int)width; if (Rectangle != null) getContentPane().remove(Rectangle); if (Ellipse != null) getContentPane().remove(Ellipse); Rectangle=new RectangleCanvas(l,w); Ellipse=new EllipseCanvas(l,w); if(length0&width0) if(e.getSource()=button_paint) if(radio_Rec.isSelected() double perimeter=(width+length)*2; double area=length*width; text_perimeter.setText(+perimeter);/周长 text_area.setText(+area); this.getContentPane().add(Rectangle,Center); if(radio_Ell.isSelected() double perimeter=3.14*(1.5*(length+width)-Math.sqrt(length*width); double area=3.14*length*width; text_perimeter.setText(+perimeter); text_area.setText(+area); this.getContentPane().add(Ellipse,Center); this.setVisible(true); public static void main(String args) new PCJFrame(); class RectangleCanvas extends Canvas private Color color; private int length,width; public RectangleCanvas(int l,int w) this.color=Color.blue; this.length=l; this.width=w; public void paint(Graphics g) g.setColor(color); g.drawRect(150,50,this.length,this.width); g.fillRect(150,50,this.length,this.width); class EllipseCanvas extends Canvas private Color color; private int length,width; public EllipseCanvas(int l,int w) this.color=Color.green; this.length=l; thi