java版计算器 源代码

/******************************************* * * 程序四：计算器 * Calculator.java * * Author: Hejie 20044440219 * ********************************************/ //简易计算器，实现+、-、*、/四个功能，原理非常简单，只是工作量大 import java.awt.*; import javax.swing.*; import java.awt.event.*; public class Calculator extends JFrame { Container ct=this.getContentPane(); JTextField text=new JTextField("0.0"); String source1=null; String source2=null; String opera=null; boolean flag1; boolean flag2; boolean flag3; JPanel pane=new JPanel(); JPanel pane1=new JPanel(); JButton b1=new JButton("1"); JButton b2=new JButton("2"); JButton b3=new JButton("3"); JButton b4=new JButton("4"); JButton b5=new JButton("5"); JButton b6=new JButton("6"); JButton b7=new JButton("7"); JButton b8=new JButton("8"); JButton b9=new JButton("9"); JButton b0=new JButton("0"); JButton b11=new JButton("+"); JButton b12=new JButton("-"); JButton b13=new JButton("*"); JButton b14=new JButton("/"); JButton b15=new JButton("."); JButton b16=new JButton("="); JButton b17=new JButton("clean"); JButton b18=new JButton("exit"); Calculator() { //初始化程序界面 super("-杰哥牌计算器-"); setBounds(200,200,200,200); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setResizable(false); text.setHorizontalAlignment(JTextField.RIGHT); text.setEditable(false); pane1.setLayout(new GridLayout(1,2,2,2)); pane.setLayout(new GridLayout(4,4,2,2)); pane.add(b1); pane.add(b2); pane.add(b3); pane.add(b11); pane.add(b4); pane.add(b5); pane.add(b6); pane.add(b12); pane.add(b7); pane.add(b8); pane.add(b9); pane.add(b13); pane.add(b0); pane.add(b15); pane.add(b16); pane.add(b14); pane1.add(b17); pane1.add(b18); b11.setForeground(Color.red); b12.setForeground(Color.red); b13.setForeground(Color.red); b14.setForeground(Color.red); b15.setForeground(Color.red); b16.setForeground(Color.red); b17.setForeground(Color.red); b18.setForeground(Color.red); ct.add(text,"North"); text.setForeground(Color.red); ct.add(pane,"Center"); ct.add(pane1,"South"); setVisible(true); Listen1 l1=new Listen1(); Listen2 l2=new Listen2(); Listen3 l3=new Listen3(); Listen4 l4=new Listen4(); b1.addActionListener(l1); b2.addActionListener(l1); b3.addActionListener(l1); b4.addActionListener(l1); b5.addActionListener(l1); b6.addActionListener(l1); b7.addActionListener(l1); b8.addActionListener(l1); b9.addActionListener(l1); b0.addActionListener(l1); b11.addActionListener(l2); b12.addActionListener(l2); b13.addActionListener(l2); b14.addActionListener(l2); b15.addActionListener(l2); b16.addActionListener(l3); b17.addActionListener(l4); b18.addActionListener(l4); } class Listen1 implements ActionListener { public void actionPerformed(ActionEvent e) { String text1=text.getText(); String text2=e.getActionCommand(); if(text1.equals("0.0")||text1.equals("+")||text1.equals("-")||text1.equals("*")||text1.equals("/")) { opera=new String(text1); text.setText(text2); } else text.setText(text1+text2); } } class Listen2 implements ActionListener { public void actionPerformed(ActionEvent e) { String text1=text.getText(); String text2=e.getActionCommand(); if(!(text1.equals("0.0")||text1.equals("+")||text1.equals("-")||text1.equals("*")||text1.equals("/"))) { source1=new String(text1); text.setText(text2); } } } class Listen3 implements ActionListener { public void actionPerformed(ActionEvent e) { String text1=text.getText(); if(!(text1.equals("+")||text1.equals("-")||text1.equals("*")||text1.equals("/"))) { source2=new String(text1); double s1=Double.parseDouble(source1); double s2=Double.parseDouble(source2); double answer; if(opera.equals("+")) answer=s1+s2; else if(opera.equals("-")) answer=s1-s2; else if(opera.equals("*")) answer=s1*s2; else//(opera.equals("/")) { if(s2==0.0) { System.out.println("除数不能为0！"); answer=0.0; } else answer=s1/s2; } text.setText(Double.toString(answer)); } } } class Listen4 implements ActionListener { public void actionPerformed(ActionEvent e) { Object butt=e.getSource(); if(butt==b17) { source1=source2=null; text.setText("0.0"); } else if(butt==b18) { System.exit(0); } } } public static void main(String [] args) { try { UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName()); } catch (Exception e) { System.err.println("Couldn't use the system look and feel:"+e); } //让程序界面呈现系统当前外观 //JFrame.setDefaultLookAndFeelDecorated(true); Calculator calculator=new Calculator(); } }