newjframe.java

这个压缩包给出了用JAVA来编写计算器的原程序

/*
 * NewJFrame.java
 *
 * Created on 2005年11月4日, 上午10:47
 */

package javaapplication1;
import java.awt.event.*;
/**
 *
 * @author  Administrator
 */
public class NewJFrame extends javax.swing.JFrame implements ActionListener{
    /** Creates new form NewJFrame */
    public NewJFrame() {
        initComponents();
        jButton1.addActionListener(this);
        jButton2.addActionListener(this);
        jButton3.addActionListener(this);
        jButton4.addActionListener(this);
        jButton5.addActionListener(this);
        jButton6.addActionListener(this);
        jButton7.addActionListener(this);
        jButton8.addActionListener(this);
        jButton9.addActionListener(this);
        jButton10.addActionListener(this);
        jButton11.addActionListener(this);
        jButton12.addActionListener(this);
        jButton13.addActionListener(this);
        jButton14.addActionListener(this);
        jButton15.addActionListener(this);
        jButton16.addActionListener(this);
        jButton17.addActionListener(this);
        jButton18.addActionListener(this);
    }
    private int action=-1;					//动作标志
    private String lastValue="";		//最后的值
    private boolean pressedOp=false;//是否按下运算符按钮
    public void actionPerformed(ActionEvent e){
        String s=e.getActionCommand();
        if(s=="."){
            if (jTextField1.getText().indexOf(".")<0) //没有小数点的数据
                jTextField1.setText(jTextField1.getText()+s);
        }
        else if (s=="BackSpace"){
            if (jTextField1.getText().length()>0)     //数据长度>0
                jTextField1.setText(jTextField1.getText().substring(0,jTextField1.getText().length()-1));
        }
        else if (s=="Clear"){
                lastValue="";
                action=-1;
                jTextField1.setText("");
                pressedOp=false;
        }
        else if (s=="1" || s=="2" ||s=="3" ||s=="4" || s=="5" ||s=="6" ||s=="7" || s=="8" ||s=="9" ||s=="0"){
            if (pressedOp){	//在此按钮之前按下了运算符，应保存文本框内容
                lastValue=jTextField1.getText();
                jTextField1.setText(s);
                pressedOp=false;	//清除运算符按下标志
            }
            else	//没有按下运算符按钮，所以在文本框内容后面追加按钮文字
                jTextField1.setText(jTextField1.getText()+s);
        }
        else{     //点击了加减乘除运算符
            if (pressedOp) return;  //连续点击运算符，不处理
            pressedOp=true;         //设置点击运算符标志
            if (lastValue!=""){     //只有两个数据都存在，才进行运算
                String currentValue=jTextField1.getText();	//当前数据
                if (lastValue.indexOf(".")>=0 || currentValue.indexOf(".")>=0){	//有小数点，应进行浮点运算
                    double v1=Double.parseDouble(lastValue);
                    double v2=Double.parseDouble(currentValue);
                    double result=0;
                    switch(action){
                        case 1:
                            result=v1+v2;
                            break;
                        case 2:
                            result=v1-v2;
                            break;
                        case 3:
                            result=v1*v2;
                            break;
                        case 4:        
                            result=(double)v1/v2;
                            break;
                    }
                    jTextField1.setText(""+result);
                }
                else{		//进行整数运算
                    int v1=Integer.parseInt(lastValue);	
                    int v2=Integer.parseInt(currentValue);
                    int result1=0;
                    double result2=0;
                    switch(action){
                        case 1:
                            result1=v1+v2;
                            break;
                        case 2:
                            result1=v1-v2;
                            break;
                        case 3:
                            result1=v1*v2;
                            break;
                        case 4:        
                            result2=(double)v1/v2;
                            break;
                    }
                    if (action==4)	//显示除法产生的浮点结果
                       jTextField1.setText(""+result2);
                    else						//显示其它运算产生的整数结果
                       jTextField1.setText(""+result1);
                }
            }
            if (s=="+") action=1;
            else if (s=="-") action=2;
            else if (s=="*") action=3;
            else if (s=="/") action=4;
       }
    }
    
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    private void initComponents() {//GEN-BEGIN:initComponents
        jTextField1 = new javax.swing.JTextField();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();
        jButton5 = new javax.swing.JButton();
        jButton6 = new javax.swing.JButton();
        jButton7 = new javax.swing.JButton();
        jButton8 = new javax.swing.JButton();
        jButton9 = new javax.swing.JButton();
        jButton10 = new javax.swing.JButton();
        jButton11 = new javax.swing.JButton();
        jButton12 = new javax.swing.JButton();
        jButton13 = new javax.swing.JButton();
        jButton14 = new javax.swing.JButton();
        jButton15 = new javax.swing.JButton();
        jButton16 = new javax.swing.JButton();
        jButton17 = new javax.swing.JButton();
        jButton18 = new javax.swing.JButton();

        getContentPane().setLayout(null);

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Java\u7b80\u6613\u8ba1\u7b97\u5668");
        jTextField1.setFont(new java.awt.Font("宋体", 1, 24));
        jTextField1.setHorizontalAlignment(javax.swing.JTextField.RIGHT);
        getContentPane().add(jTextField1);
        jTextField1.setBounds(20, 30, 450, 30);

        jButton1.setFont(new java.awt.Font("宋体", 1, 24));
        jButton1.setText("1");
        getContentPane().add(jButton1);
        jButton1.setBounds(20, 70, 90, 40);

        jButton2.setFont(new java.awt.Font("宋体", 1, 24));
        jButton2.setText("2");
        getContentPane().add(jButton2);
        jButton2.setBounds(140, 70, 90, 40);

        jButton3.setFont(new java.awt.Font("宋体", 1, 24));
        jButton3.setText("3");
        getContentPane().add(jButton3);
        jButton3.setBounds(260, 70, 90, 40);

        jButton4.setFont(new java.awt.Font("宋体", 1, 24));
        jButton4.setText("4");
        getContentPane().add(jButton4);
        jButton4.setBounds(380, 70, 90, 40);

        jButton5.setFont(new java.awt.Font("宋体", 1, 24));
        jButton5.setText("5");
        getContentPane().add(jButton5);
        jButton5.setBounds(20, 120, 90, 40);

        jButton6.setFont(new java.awt.Font("宋体", 1, 24));
        jButton6.setText("6");
        getContentPane().add(jButton6);
        jButton6.setBounds(140, 120, 90, 40);

        jButton7.setFont(new java.awt.Font("宋体", 1, 24));
        jButton7.setText("7");
        getContentPane().add(jButton7);
        jButton7.setBounds(260, 120, 90, 40);

        jButton8.setFont(new java.awt.Font("宋体", 1, 24));
        jButton8.setText("8");
        getContentPane().add(jButton8);
        jButton8.setBounds(380, 120, 90, 40);

        jButton9.setFont(new java.awt.Font("宋体", 1, 24));
        jButton9.setText("9");
        getContentPane().add(jButton9);
        jButton9.setBounds(20, 170, 90, 40);

        jButton10.setFont(new java.awt.Font("宋体", 1, 24));
        jButton10.setText("0");
        getContentPane().add(jButton10);
        jButton10.setBounds(140, 170, 90, 40);

        jButton11.setFont(new java.awt.Font("宋体", 1, 24));
        jButton11.setText(".");
        getContentPane().add(jButton11);
        jButton11.setBounds(260, 170, 90, 40);

        jButton12.setFont(new java.awt.Font("宋体", 1, 24));
        jButton12.setText("Clear");
        getContentPane().add(jButton12);
        jButton12.setBounds(20, 270, 210, 40);

        jButton13.setFont(new java.awt.Font("宋体", 1, 24));
        jButton13.setText("+");
        getContentPane().add(jButton13);
        jButton13.setBounds(20, 220, 90, 40);

        jButton14.setFont(new java.awt.Font("宋体", 1, 24));
        jButton14.setText("-");
        getContentPane().add(jButton14);
        jButton14.setBounds(140, 220, 90, 40);

        jButton15.setFont(new java.awt.Font("宋体", 1, 24));
        jButton15.setText("*");
        getContentPane().add(jButton15);
        jButton15.setBounds(260, 220, 90, 40);

        jButton16.setFont(new java.awt.Font("宋体", 1, 24));
        jButton16.setText("/");
        getContentPane().add(jButton16);
        jButton16.setBounds(380, 220, 90, 40);

        jButton17.setFont(new java.awt.Font("宋体", 1, 24));
        jButton17.setText("=");
        getContentPane().add(jButton17);
        jButton17.setBounds(380, 170, 90, 40);

        jButton18.setFont(new java.awt.Font("宋体", 1, 24));
        jButton18.setText("BackSpace");
        getContentPane().add(jButton18);
        jButton18.setBounds(260, 270, 210, 40);

        java.awt.Dimension screenSize = java.awt.Toolkit.getDefaultToolkit().getScreenSize();
        setBounds((screenSize.width-492)/2, (screenSize.height-359)/2, 492, 359);
    }//GEN-END:initComponents
    
    
    // 变量声明 - 不进行修改//GEN-BEGIN:variables
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton10;
    private javax.swing.JButton jButton11;
    private javax.swing.JButton jButton12;
    private javax.swing.JButton jButton13;
    private javax.swing.JButton jButton14;
    private javax.swing.JButton jButton15;
    private javax.swing.JButton jButton16;
    private javax.swing.JButton jButton17;
    private javax.swing.JButton jButton18;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JButton jButton5;
    private javax.swing.JButton jButton6;
    private javax.swing.JButton jButton7;
    private javax.swing.JButton jButton8;
    private javax.swing.JButton jButton9;
    private javax.swing.JTextField jTextField1;
    // 变量声明结束//GEN-END:variables
    
}