计算器修正版

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.ArrayList;
import java.util.EmptyStackException;
import java.util.List;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JSeparator;
import javax.swing.JTextField;
import javax.swing.event.MenuEvent;
import javax.swing.event.MenuListener;

public class MyCaculatorUseStacks implements MenuListener, ActionListener {
	JPanel mainp,p1,p2,p3,p4;
	JTextField jt1;
	JTextField jt2;
	JMenuItem mnuCopy;
	JMenuItem mnuPaste;
	JButton bM;
	
	boolean isDouble = false;// 是否为实数
	double n3;
	MyStack<Integer> opPool = new MyStack<Integer>();//操作符堆栈
	MyStack<Double> opArg = new MyStack<Double>();
	
	StringBuffer tempsbf =new StringBuffer();
	StringBuffer buf = new StringBuffer();
	StringBuffer copyBoard = new StringBuffer(40);// 剪贴板
	StringBuffer memory = new StringBuffer(40);// M系列
	StringBuffer str = new StringBuffer();//缓冲器
	
	public MyCaculatorUseStacks()
	 {   
		p1=new JPanel();
		p1.setLayout(new GridLayout(2,1,10,10));
		JMenuBar mnuNotepad=new JMenuBar();
		JMenu mnuEdit=new JMenu("编辑(E)");
		mnuEdit.setMnemonic(KeyEvent.VK_E);
		JMenu mnuCheck=new JMenu("查看(V)");
		mnuCheck.setMnemonic(KeyEvent.VK_V);
		JMenu mnuHelp=new JMenu("帮助(H)");
		mnuCopy=new JMenuItem("复制(C)");
		mnuPaste=new JMenuItem("粘贴(P)");
	    JMenuItem mnuVisit=new JMenuItem("查看帮助(V)");
	    JMenuItem mnuAbout=new JMenuItem("关于计算器(A)");
	    
	    JSeparator sep=new JSeparator();
	    jt1=new JTextField("0.");
		jt1.setHorizontalAlignment(JTextField.RIGHT);
		jt1.setEnabled(false);
		
		jt2 = new JTextField("运算过程表达式");
		jt2.setHorizontalAlignment(JTextField.RIGHT);
		
		
		jt1.setSelectedTextColor(Color.yellow);
		jt1.setEditable(true);
		jt2.setSelectedTextColor(Color.red);
		jt2.setEditable(true);
		
		
		mnuEdit.addMenuListener(this);
		mnuCheck.addMenuListener(this);
		mnuHelp.addMenuListener(this);
		mnuCopy.addActionListener(this);
		mnuPaste.addActionListener(this);
		mnuVisit.addActionListener(this);
		mnuAbout.addActionListener(this);
		mnuNotepad.add(mnuEdit);
		mnuNotepad.add(mnuCheck);
		mnuNotepad.add(mnuHelp);
		mnuEdit.add(mnuCopy);
		mnuEdit.add(mnuPaste);
		mnuEdit.add(sep);
		mnuHelp.add(mnuVisit);
		mnuHelp.add(sep);
		mnuHelp.add(mnuAbout);
		
		p1.setLayout(new GridLayout(3,1));
		p1.add(mnuNotepad);
		p1.add(jt1);
		p1.add(jt2);
		
		p2=new JPanel();
		p2.setLayout(new FlowLayout(FlowLayout.CENTER));
		bM = new JButton(" ");
		bM.setEnabled(false);
		p2.add(bM);
		
		
		JButton b25=new JButton("Backspace");
		b25.addActionListener(this);
		JButton b26=new JButton("CE");
		b26.addActionListener(this);
		JButton b27=new JButton("C");
		b27.addActionListener(this);

		p2.add(b25);
		p2.add(b26);
		p2.add(b27);
		p3=new JPanel();
		p3.setLayout(new GridLayout(4,6));
		
		JButton button1=new JButton("MC");
		button1.addActionListener(this);
		JButton button2=new JButton("7");
		button2.addActionListener(this);
		JButton button3=new JButton("8");
		button3.addActionListener(this);
		JButton button4=new JButton("9");
		button4.addActionListener(this);
		JButton button5=new JButton("/");
		button5.addActionListener(this);
		JButton button6=new JButton("sqrt");
		button6.addActionListener(this);
		JButton button7=new JButton("MR");
		button7.addActionListener(this);
		JButton button8=new JButton("4");
		button8.addActionListener(this);
		JButton button9=new JButton("5");
		button9.addActionListener(this);
		JButton button10=new JButton("6");
		button10.addActionListener(this);
		JButton button11=new JButton("*");
		button11.addActionListener(this);
		JButton button12=new JButton("%");
		button12.addActionListener(this);
		JButton button13=new JButton("MS");
		button13.addActionListener(this);
		JButton button14=new JButton("1");
		button14.addActionListener(this);
		JButton button15=new JButton("2");
		button15.addActionListener(this);
		JButton button16=new JButton("3");
		button16.addActionListener(this);
		JButton button17=new JButton("-");
		button17.addActionListener(this);
		JButton button18=new JButton("1/x");
		button18.addActionListener(this);
		JButton button19=new JButton("M+");
		button19.addActionListener(this);
		JButton button20=new JButton("0");
		button20.addActionListener(this);
		JButton button21=new JButton("+/-");
		button21.addActionListener(this);
		JButton button22=new JButton(".");
		button22.addActionListener(this);
		JButton button23=new JButton("+");
		button23.addActionListener(this);
		JButton button24=new JButton("=");
		button24.addActionListener(this);
		p3.add(button1);p3.add(button2);
		p3.add(button3);p3.add(button4);
		p3.add(button5);p3.add(button6);
		p3.add(button7);p3.add(button8);
		p3.add(button9);p3.add(button10);
		p3.add(button11);p3.add(button12);
		p3.add(button13);p3.add(button14);
		p3.add(button15);p3.add(button16);
		p3.add(button17);p3.add(button18);
		p3.add(button19);p3.add(button20);
		p3.add(button21);p3.add(button22);
		p3.add(button23);p3.add(button24);
		p3.setSize(250,250);
		mainp=new JPanel();
		mainp.setLayout(new GridLayout(3,1));
		mainp.add(p1);
		mainp.add(p2);
		mainp.add(p3);
		
		JFrame f = new JFrame();
		f.getContentPane().add(mainp);
		f.setTitle("计算器");
		f.setSize(350,350);
		f.setVisible(true);
		f.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				System.exit(0);
			}});
	}

	public void menuCanceled(MenuEvent e) {
		
	}

	public void menuDeselected(MenuEvent e) {
		
	}

	public void menuSelected(MenuEvent e) {
		
	}

	public void actionPerformed(ActionEvent e) {
		String s= e.getActionCommand();
		
		if(s.equals("复制(C)")){
			String temp = jt1.getText().trim();		
			copyBoard.replace(0, copyBoard.length(), temp);
		}
		
		else if(s.equals("粘贴(P)")){
			jt1.setText(copyBoard.toString());		
		}
		
		else if(s.equals("查看帮助(V)")){
			
		}
		
		else if(s.equals("关于计算器(A)")){
			JOptionPane.showMessageDialog(null, "designed by YJQ!");
		}
		
		else if(s.equals("Backspace")){
			if (!jt1.getText().trim().equals("0.")) {
				// 如果文本框中有内容
				
				str.setLength(0);
				str.append(jt1.getText().trim());
				if(str.indexOf(".") == (str.length()-1)){
					str.setLength(str.length()-1);
				}
				if (str.length() > 1){
					if(str.indexOf(".")!= -1){
						
						str.setLength(str.length() - 1);
						jt1.setText(str.toString());
						System.out.println(str.toString());
					}
					else
					{
						
						str.setLength(str.length()-1);
						jt1.setText(str.toString()+".");
						System.out.println(str.toString());
					}
				} 
				else {
					jt1.setText("0.");
					str.setLength(0);
				}
			}
		}
		else if(s.equals("CE")){
			jt1.setText("0.");
			jt1.setText("0.");
			
		}
		else if(s.equals("C")){
			init();
		}
		else if(s.equals("MC")){
			// 如果是MC则清除缓冲区
			memory.setLength(0);
			bM.setText(" "); 
		}
		else if(s.equals("MR")){
			// 如果按键为MR则恢复缓冲区的数到文本框
			jt1.setText(memory.toString());
		}
		else if(s.equals("MS")){
		// 如果按键为MS则将文本框的数存入缓冲区
			try{
				n3 = Double.parseDouble(jt1.getText().trim());
				memory.setLength(0);
				memory.append(n3);
				bM.setText("M");
			}
			catch(Exception ex){
				ex.printStackTrace();
				JOptionPane.showMessageDialog(null, "文本不是实数，不能被存储！");
			};
		}
		
		else if(s.equals("M+")){
			// 如果按键为MS则将文本框值与缓冲区的数相加但不显示结果
			String temp1 = jt1.getText().trim();
			double dtemp = Double.parseDouble(temp1);
			String temp2 = memory.toString();
			dtemp += Double.parseDouble(temp2);
			temp1 = String.valueOf(dtemp);
			memory.replace(0, memory.length(), temp1);			
			
		}
		else if(s.equals("sqrt")){
			
			String temp = jt1.getText().trim();
			double dtemp = Double.parseDouble(temp);
			if(dtemp >= 0){
				tempsbf.replace(0, tempsbf.length(),("sqrt("+tempsbf+")"));
				dtemp = Math.sqrt(dtemp);
				str.setLength(0);
				str.append(dtemp);
				
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
			}
			else{
				JOptionPane.showMessageDialog(null, "sqrt的操作数不能为负数");
			};
		}
		
		else if(s.equals("+/-")){
			String temp = jt1.getText().trim();
			double dtemp = Double.parseDouble(temp);
			tempsbf.replace(0, tempsbf.length(),("(-"+tempsbf+")"));
			dtemp = -dtemp;
			str.setLength(0);
			str.append(""+dtemp);
			jt1.setText(str.toString());
			if(str.substring(str.length()-2, str.length()).equals(".0")){
				str.setLength(str.length()-1);
			}
			jt1.setText(str.toString());
		}
		
		else if(s.equals("%")){
			if(isDouble){
			double dtemp = Double.parseDouble(jt1.getText().trim())*100;
			jt1.setText(""+dtemp+"%");
			}
		}
		
		else if(s.equals("1/x")){
			String temp = jt1.getText().trim();
			double dtemp = Double.parseDouble(temp);
			if(dtemp != 0){
				tempsbf.replace(0, tempsbf.length(),"1/("+tempsbf+")");
				dtemp = 1/dtemp;
				str.setLength(0);
				str.append(""+dtemp);
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
			}
			else{
				JOptionPane.showMessageDialog(null, "1/x的操作数不能为0");
			}
		}
		
		else if(s.equals("+")){
			buf.replace(0, buf.length(),""+buf + tempsbf + "+");
			tempsbf.setLength(0);
			if(str.length()!=0){
				String temp = str.toString().trim();
				double dtemp = Double.parseDouble(temp);
					opArg.push(dtemp);
					if (opPool.isEmpty()||opArg.getStackSize()< 2){
						if(opPool.isEmpty()){
							opArg.clear();
							opArg.push(dtemp);
							opPool.push(1);
						}
						else {
							opPool.clear();
						}
						jt1.setText("" + opArg.getTopObjcet());
					}
				else {
					operate(opPool,opArg);
					opPool.push(1);
				
				}
				
				str.replace(0,str.length(),""+opArg.getTopObjcet());
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
				str.setLength(0);
			}
		}
		else if(s.equals("-")){
			buf.replace(0, buf.length(),""+buf+tempsbf + "-");
			tempsbf.setLength(0);
			if(str.length()!= 0){
				String temp = str.toString().trim();
				double dtemp = Double.parseDouble(temp);
				if(opArg.getStackSize()<2){
					opArg.push(dtemp);
				}
				if (opPool.isEmpty()||opArg.getStackSize()==1){
					opPool.clear();
					opPool.push(2);
					jt1.setText("" + opArg.getTopObjcet());
				}
				else {
					operate(opPool,opArg);
					opPool.push(2);
					
				}
				str.replace(0,str.length(),""+opArg.getTopObjcet());
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
				str.setLength(0);
			}
			
		}
		else if(s.equals("*")){
			buf.replace(0, buf.length(),"("+buf+ tempsbf +")"+"*");
			tempsbf.setLength(0);
			if(str.length() != 0){
				String temp = str.toString().trim();
				double dtemp = Double.parseDouble(temp);
				if(opArg.getStackSize()<2){
					opArg.push(dtemp);
				}
				if (opPool.isEmpty()||opArg.getStackSize()==1){
					opPool.clear();
					opPool.push(3);
					jt1.setText("" + opArg.getTopObjcet());
				}
				else {
					operate(opPool,opArg);
					opPool.push(3);
					
				}
				str.replace(0,str.length(),""+opArg.getTopObjcet());
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
				str.setLength(0);
			}
		}
		else if(s.equals("/")){
			buf.replace(0, buf.length(), "("+buf+tempsbf+")/");
			tempsbf.setLength(0);
			if(str.length() != 0){
				String temp = str.toString().trim();
				double dtemp = Double.parseDouble(temp);
				if(opArg.getStackSize()<2){
					opArg.push(dtemp);
				}
				if (opPool.isEmpty()||opArg.getStackSize()==1){
					opPool.clear();
					opPool.push(4);
					jt1.setText("" + opArg.getTopObjcet());
				}
				else {
					operate(opPool,opArg);
					opPool.push(4);
					
				}
				
				str.replace(0,str.length(),""+opArg.getTopObjcet());
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
					
				}
				jt1.setText(str.toString());
				str.setLength(0);
			}
		}
		else if(s.equals(".")){
			if(str.length()!= 0 && str.toString().trim().indexOf(".") == -1 ){
					str.append(s);
					tempsbf.append(s);
					jt1.setText(str.toString());
					
			}
			else if(str.length()== 0){
				str.append("0"+s);
				tempsbf.append("0"+s);
			}
			isDouble = true;
		}
		
		else if(s.equals("=")){
			if(str.length()!= 0){
				double dtemp = Double.parseDouble(str.toString().trim());
					opArg.push(dtemp);
				if (opPool.isEmpty()||opArg.getStackSize()< 2){
					if(opPool.isEmpty()){
						opArg.clear();
						opArg.push(dtemp);
					}
					opPool.clear();
					jt1.setText("" + opArg.getTopObjcet());
				}
				else {
					operate(opPool,opArg);
				}
				buf.append(tempsbf.toString().trim());
				tempsbf.setLength(0);
				System.out.println(buf+"="+opArg.getTopObjcet());
				jt2.setText(buf.toString()+ "="+opArg.getTopObjcet());
				buf.setLength(0);
				str.replace(0,str.length(),""+opArg.getTopObjcet());
				if(str.substring(str.length()-2, str.length()).equals(".0")){
					str.setLength(str.length()-1);
				}
				jt1.setText(str.toString());
				
				str.setLength(0);
			}
			
		}
		// 如果选择的是"0"这个数字键
		else if (s.equals("0")){ 
			
			if (str.length()== 0){
				str.append(s);
				tempsbf.append(s);
			}
			else if(str.toString().equals("0")){
				
			}
			else if(str.toString().equals("0.")){
				if(isDouble){ //为浮点数时  0加到   str 中去
					jt1.setText(str.append(s).toString());
					tempsbf.append(s);
				}
			}
			else{
				jt1.setText(str.append(s).toString());
				tempsbf.append(s);
			}
		}
		
		else{
			str.append(s);
			tempsbf.append(s);
			if(str.toString().indexOf(".") != -1){
				jt1.setText(str.toString());
			}
			else jt1.setText(str.toString()+".");
			
		}
	}
	private void operate(MyStack<Integer> opPool,MyStack<Double> opArg){
		
		double opRight = opArg.pop();
		double opLeft = opArg.pop();
		
		switch (opPool.pop()) {
		case 1:
			opLeft += opRight;
			
			break;
		case 2:
			opLeft -= opRight;
			break;
		case 3:
			opLeft *= opRight;
			break;
		case 4:
			if(opRight != 0) opLeft /= opRight;
			else JOptionPane.showMessageDialog(null, "除数不能为0");
			break;
		}
		opArg.push(opLeft);
		
	}
	private void init() {
		isDouble = false;
		jt1.setText("0.");
		jt2.setText("0.");
		str.setLength(0);
		buf.setLength(0);
		tempsbf.setLength(0);
		opPool.clear();
		opArg.clear();
	}

	public static void main(String args[]){
		new MyCaculatorUseStacks();
	}
	
	private class MyStack<Object>{
		private List<Object> pool= new ArrayList<Object>();
		
		public MyStack(){
			
		}
		
		public void clear() {   
			pool.clear();   
		} 
		
		public boolean isEmpty(){
			return pool.isEmpty();   
		}
		
		/**  
		 * 获取栈顶元素
		 * */
		public Object  getTopObjcet() {
			if (isEmpty()) return null;
			else return pool.get(0);
		}
		
		/**  
		 * 弹出栈操作  
		 * */
		public Object pop(){
			 if (isEmpty()) {throw new EmptyStackException();} 
			 return pool.remove(pool.size() - 1);
		}
		
		/**  
		 * 压入栈操作  
		 * */
		public void push(Object i){
			pool.add(i);
		}
		/**  
		* 获取当前栈大小  
		* */  
		public int getStackSize(){
			if (isEmpty()) return 0;
			else return pool.size();
		}
	}
}