java程序计算器带括号和异常处理的.doc

import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.event.*;import java.awt.List;import javax.script.ScriptEngine;import javax.script.ScriptEngineManager;import javax.script.ScriptException;public class MessageBoard extends Framepublic static void main(String args) final Frame jf = new Frame(计算器); jf.setSize(250,275); /设置窗口长宽jf.setResizable(false); /设置窗体大小不可更改 /*添加文本框*/jf.setLayout(null); /组件不会随窗口的大小而改变final JTextField jt1 = new JTextField();jt1.setHorizontalAlignment(JTextField.RIGHT); /设置文本框右对齐jt1.setEditable(false); /设置文本框不可编辑jt1.setBounds(10,50,233,20);jf.add(jt1);/*添加按钮*/设置0键final JButton b0 = new JButton(0);b0.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+0););/设置1键final JButton b1 = new JButton(1);b1.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e)jt1.setText(jt1.getText()+1); );/设置2键final JButton b2 = new JButton(2);b2.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+2); );/设置3键final JButton b3 = new JButton(3);b3.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) /监听器接口定义好的 ActionEvent类型 e是参数名 jt1.setText(jt1.getText()+3); );/设置4键final JButton b4 = new JButton(4);b4.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+4); );/设置5键final JButton b5 = new JButton(5);b5.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+5); );/设置6键final JButton b6 = new JButton(6);b6.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+6); );/设置7键final JButton b7 = new JButton(7);b7.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+7); );/设置8键final JButton b8 = new JButton(8);b8.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+8); );/设置9键final JButton b9 = new JButton(9);b9.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+9); );/设置加号键final JButton badd = new JButton(+);badd.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+); );/设置减号键final JButton bminus = new JButton(-);bminus.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+-); );/设置乘号键final JButton bmulti = new JButton(*);bmulti.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+*); );/设置除号键final JButton bdivide = new JButton(/);bdivide.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+/); );/设置等号键final JButton bequal = new JButton(=);bequal.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) ScriptEngineManager sem = new ScriptEngineManager(); ScriptEngine se = sem.getEngineByName(js);tryString reslut = se.eval(jt1.getText().toString();jt1.setText(reslut); catch (ScriptException evt)JOptionPane.showMessageDialog(null,表达式不合法！); );/设置小数点号键final JButton bpoint = new JButton(.);bpoint.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+.); );/设置左括号键final JButton bleft = new JButton();bleft.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+(); );/设置右括号键final JButton bright = new JButton();bright.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+); );/设置负号键final JButton bfuhao = new JButton(+-);bfuhao.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(jt1.getText()+-); );/设置清0键final JButton bce = new JButton(CE);bce.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) jt1.setText(); );/设置退格键final JButton bback = new JButton(Backspace);bback.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) String message;int leng=jt1.getText().length();message=jt1.getText();if(leng=0)JOptionPane.showMessageDialog(null, 以无输入内容); /当退格到没有输入是弹出消息框提示elsejt1.setText(message.substring(0,leng-1); /设置文本框的内容没点一次退格减一个数 );/按钮布局 b0.setBounds(10,228,45,35);b1.setBounds(10,190,45,35); /前2个代表x，y坐标 后面的是 宽和高b2.setBounds(57,190,45,35);b3.setBounds(104,190,45,35);b4.setBounds(10,151,45,35);b5.setBounds(57,151,45,35);b6.setBounds(104,151,45,35);b7.setBounds(10,112,45,35);b8.setBounds(57,112,45,35);b9.setBounds(104,112,45,35);badd.setBounds(151,228,45,35);bminus.setBounds(151,190,45,35);bmulti.setBounds(151,151,45,35);bdivide.setBounds(151,112,92,35);bequal.setBounds(198,228,45,35);bpoint.setBounds(104,228,45,35);bleft.setBounds(198,151,45,35);bright.setBounds(198,190,45,35);bfuhao.setBounds(57,228,45,35);bce.setBounds(128,75,115,35);bback.setBounds(10,75,115,35);/向jf中添加控件jf.add(b0);jf.add(b1);jf.add(b2);jf.add(b3);jf.add(b4);jf.add(b5);jf.add(b6);jf.add(b7);jf.add(b8);jf.add(b9);jf.