java swing 一元二次方程.doc

AWrongException.javapackage fangcheng;public class AWrongException extends Exception public AWrongException(String s) super(s);Rootx1x2.javapackage fangcheng;import java.awt.BorderLayout;import java.awt.Color;import java.awt.Font;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.JTextField;public class Rootx1x2 extends JFrame implements RootInterface,ActionListener /实现RootInterfacedouble a,b,c, b24ac, x1,x2;String y1,y2;JTextField textA,textB,textC; /数据对象的视图JTextArea roottext;JTextArea showArea; /数据对象的视图JButton button1,button2,button3; /控制器对象 Root root;public Rootx1x2(String astr,String bstr,String cstr) throws AWrongException, ExceptionsetTitle(求一元二次方程根);setBounds(300,300,150,300);init();setResizable(false);setVisible(true);setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);void init() throws AWrongException, Exceptionroot =new Root(0, 0, 0);textA=new JTextField(5);textB=new JTextField(5);textC=new JTextField(5);textA.setText(0);textB.setText(0);textC.setText(0);showArea=new JTextArea();button1= new JButton(求根);button2= new JButton(清空);button3= new JButton(退出);JPanel jp= new JPanel();jp.add(new JLabel(求一元二次方程根);jp.add(new JLabel(请输入系数a);jp.add(textA);jp.add(new JLabel(请输入系数b);jp.add(textB);jp.add(new JLabel(请输入系数c);jp.add(textC);jp.add(new JLabel(计08-5班 X S L);jp.setFont(new Font(Serif,Font.PLAIN,25);jp.setForeground(Color.pink);roottext = new JTextArea(4,15);String a=null,b=null,c=null;a=textA.getText();b=textB.getText();c=textC.getText();jp.add(button1);jp.add(button2);jp.add(button3);jp.add(roottext);add(jp);button1.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) if(Double.valueOf(textA.getText()=0)roottext.setForeground(Color.red);roottext.setText(二次项系数不能为零！);else if(root.b24ac(Double.valueOf(textA.getText(),Double.valueOf(textB.getText(),Double.valueOf(textC.getText()root.root_x1x2(Double.valueOf(textA.getText(),Double.valueOf(textB.getText(),Double.valueOf(textC.getText();roottext.setForeground(new Color(0,50,0);roottext.setText(一元二次方程根为：+root.getx1()+ , +root.getx2();elseroot.root_x1x2(Double.valueOf(textA.getText(),Double.valueOf(textB.getText(),Double.valueOf(textC.getText();roottext.setForeground(new Color(255,0,0);roottext.setForeground(Color.black);roottext.setText(一元二次方程根为：+root.gety1()+root.gety2()+i););button2.addActionListener(new ActionListener()public void actionPerformed(ActionEvent e)textA.setText(0);textB.setText(0);textC.setText(0);roottext.setText(null); roottext.setForeground(Color.black);); button3.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) System.exit(0); ); button1.addActionListener(this); button2.addActionListener(this); button3.addActionListener(this); public static void main(String args) throws AWrongException, ExceptionRootx1x2 r =new Rootx1x2(1,1,1);public void inputABC(String astr, String bstr, String cstr) throws AWrongException, Exception / TODO 自动生成方法存根public boolean b24ac(double a, double b, double c) / TODO 自动生成方法存根return false;public void root_x1x2(double a, double b, double c) / TODO 自动生成方法存根public void actionPerformed(ActionEvent e) / TODO 自动生成方法存根RootInterface.javapackage fangcheng;public interface RootInterfacepublic void inputABC(String astr,String bstr,String cstr) throws AWrongException, Exception;public boolean b24ac(double a,double b,double c); /求b*b-4*a*cpublic void root_x1x2(double a,double b,double c); /求根Root.javapackage fangcheng;import java.text.DecimalFormat;public class Root implements RootInterface /实现RootInterfacedouble a,b,c, b24ac, x1,x2;String y1,y2;public Root(String astr, String bstr, String cstr) throws AWrongException, ExceptioninputABC(astr,bstr,cstr);root_x1x2(a,b,c);public double getx1()return x1;public double getx2()return x2;public String gety1()return y1;public String gety2()return y2;public void inputABC(String astr,String bstr,String cstr) throws AWrongException, Exceptiona=Double.valueOf(astr);b=Double.valueOf(bstr);c=Double.valueOf(cstr); public boolean b24ac(double a,double b,double c)b24ac=b*b-4*a*c;if(b24ac=0&a!=0)return true;elsereturn false;public void root_x1x2(double a,double b,double c)DecimalFormat df = new java.text.DecimalFormat(0.00);if( b24ac=0&a!=0)x1=Double.valueOf(df.format(-1*b+Math.sqrt(b*b-4*a*c)/(2*a); x2=Do