listener.java

很完善的计算器哦

package calculator;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JOptionPane;


public class Listener implements ActionListener
{		
	
	private Calculator c;
	private Object source;		
	private char numberChar = ' ';
	
	public Listener(Calculator c)
	{
		this.c = c;
	}
	
	public void actionPerformed(ActionEvent e)
	{
		source = e.getSource();

		if( source == c.b[19] || source == c.b[20] || source == c.b[21] ||
			source == c.b[25] || source == c.b[26] || source == c.b[27] || 
		    source == c.b[31] || source == c.b[32] || source == c.b[33] )		    
			//添加数字1-9
			addNumberOrPoint();
		
		else if(source == c.b[37])//添加数字0
		{
			if(c.getStr1().length() > 40 || c.getStr2().length() > 40)
				return ;	
			
			if(c.getStr1().length() == 0)
    			c.setStr1(c.getStr1().append('0'));
			
            if(c.getStr1().length() > 1 && c.getStr1().indexOf("0") == 0 && c.getStr1().indexOf(".") == -1)
            	c.getStr1().deleteCharAt(0);

        	if(c.getStr1().length() != 0 && c.getStr2().length() == 0)
        	{
        		if(!c.getNewFlag())
        		{
        			if(!c.getPointFlag())
        		    	c.setStr1(c.getStr1().append('0'));
        			c.getDisplay().setText(c.getStr1().toString());
        		}
        		
        		else if(c.getDoubleOperatorFlag() != -1)
        		{
        			c.getDisplay().setText(c.getStr2().toString() + '0');
        			c.setStr2(c.getStr2().append('0'));
        		}
        	    	else
        		    	c.getDisplay().setText("0");
        	}
        	else if(c.getStr1().length() != 0 && c.getStr2().length() != 0)
        	{
        		c.getDisplay().setText(c.getStr2().toString() + '0');
    			c.setStr2(c.getStr2().append('0'));
        	}
		}
		
		else if(source == c.b[38])//正负号
	    {
			if (c.getStr1().length() == 0)
				return ;
			
			if(c.getDoubleOperatorFlag() != -1 && !c.getChangeFlag() && c.getStr2().length() == 0)
				return ;
			
			if (c.getStr1().length() != 0 && !c.getChangeFlag())				
			    	if(!c.getNewFlag())				
		        	{
			    		c.setStr1(c.getStr1().insert(0, '-'));						
						c.getDisplay().setText(c.getStr1().toString());
						c.setChangeFlag(true);
		        	}
		        	else if (c.getStr2().length() == 0)
		        			return ;
		        		 else 
		        		 {
		        			c.setStr2(c.getStr2().insert(0, '-'));	
		        			c.getDisplay().setText(c.getStr2().toString());
							c.setChangeFlag(true);
		        		 }								
			else if (c.getChangeFlag()) 				
			     	if (!c.getNewFlag())
		        	{
			     		if(c.getStr1().length() == 0)
			     			return ;
			     		c.setStr1(c.getStr1().deleteCharAt(0));
						c.getDisplay().setText(c.getStr1().toString());
						c.setChangeFlag(false);
		          	}
		        	else
		        	{
		        		if(c.getStr2().length() == 0)
			     			return ;
		        		c.setStr2(c.getStr2().deleteCharAt(0));
						c.getDisplay().setText(c.getStr2().toString());
						c.setChangeFlag(false);
		        	}
	    }	
		
		else if(source == c.b[39])//小数点
			if (!c.getNewFlag())
			{
				if (c.getStr1().length() != 0 && c.getPointFlag())				
					addNumberOrPoint();
				else
				{
					if (c.getStr1().length() == 0)
					{
						c.getStr1().append("0.");
						c.getDisplay().setText("0.");						
					}
				}
				c.setPointFlag(false);
			}
			else
			{
				if (c.getStr2().length() != 0 && c.getPointFlag() == true)
					addNumberOrPoint();
				else
				{
					if (c.getStr2().length() == 0)
					{
						c.getStr2().append("0.");
						c.getDisplay().setText("0.");
					}
				}
				c.setPointFlag(false);
			}	
					
        else if(source == c.b[7] || source == c.b[9] || source == c.b[15] || 
        		source == c.b[16] || source == c.b[17] || source == c.b[22] ||
				source == c.b[28] || source == c.b[34] || source == c.b[40])
			// 两个数运算
		{
        	if(c.getStr1().length() == 0)
        		c.getStr1().append(0);
        	if(c.getStr1().length() != 0 || c.getMemoryDisplayFlag())
			{
				doubleCalculate();
				evaluateDoubleOperator();
		    }
        }
		
        else if(source == c.b[0] || source == c.b[1] || source == c.b[2] || 
        		source == c.b[4] || source == c.b[5] || source == c.b[6] ||
        		source == c.b[8] || source == c.b[10] || source == c.b[11] || 
        		source == c.b[13] ||source == c.b[14] || source == c.b[23] ||
        		source == c.b[29] || source == c.b[35] )
        	//单个数运算
        {
        	if(c.getStr1().length() == 0)
        		c.getStr1().append(0);
        	if(!c.getNewFlag())
            	firstSingleCalculate();
        	else
        		secondSingleCalculate();
        }
        	
		
        else if(source == c.b[3])//PI
        {
        	c.getDisplay().setText(Double.toString(Math.PI));
        	if(!c.getNewFlag())
        	{       		
            	c.getStr1().setLength(0);
            	c.getStr1().append(Math.PI);
        	}
        	else
        	{
        		c.getStr2().setLength(0);
            	c.getStr2().append(Math.PI);
        	}
        	if(c.getMemoryPlusFlag())
        		c.setMemoryPlusFlag(false);
        	c.setPointFlag(true);
        }
		
        else if(source == c.b[12])//e
        {
        	c.getDisplay().setText(Double.toString(Math.E));
        	if(!c.getNewFlag())
        	{       		
            	c.getStr1().setLength(0);
            	c.getStr1().append(Math.E);
        	}
        	else
        	{
        		c.getStr2().setLength(0);
            	c.getStr2().append(Math.E);
        	}
        	if(c.getMemoryPlusFlag())
        		c.setMemoryPlusFlag(false);
        	c.setPointFlag(true);
        }
		
        else if(source == c.b[41])//等于
        {
        	doubleCalculate();
        	c.setRefreshFlag(true);
        }
		
        else if(source == c.b[42])//about
        {
        	JOptionPane.showMessageDialog
        	(null, "                            欢迎使用 \n" +
        			"               多功能计算器 v1.0 Beta\n" +     			
        			"有问题或需要更多帮助请查看 readme.txt");
        }
		
        else if(source == c.b[43])//退格
        {
        	if(!c.getNewFlag())
        	{
        		if(c.getStr1().length() < 1)
        			return ;
        		c.getStr1().setLength(c.getStr1().length() - 1);
        		c.getDisplay().setText(c.getStr1().toString());
        	}
        	else
        	{
        		if(c.getStr2().length() < 1)
        			return ;
        		c.getStr2().setLength(c.getStr2().length() - 1);
        		c.getDisplay().setText(c.getStr2().toString());
        	}        		
        }
		
        else if(source == c.b[44])//CE
        {
        	if(!c.getNewFlag())
        	{
        		c.getStr1().setLength(0);     		
        		c.setDivZeroFlag(false);
        		c.setDoubleOperatorFlag(-1);
        		c.setSingleOperatorFlag(-1);       		
        	}
        	else
        	{
        		c.getStr2().setLength(0);
        	}
        	c.getDisplay().setText("0");  
        	c.setPointFlag(true);
    		c.setChangeFlag(false);
        }
		
        else if(source == c.b[45])//C
        {
        	c.getDisplay().setText("0");
        	c.setNewFlag(false);
        	c.setPointFlag(true);
        	c.setChangeFlag(false);
        	c.setDivZeroFlag(false);
        	c.setDoubleOperatorFlag(-1);
        	c.setSingleOperatorFlag(-1);
        	c.getStr1().setLength(0);
        	c.getStr2().setLength(0);
        }
		
        else if(source == c.b[36])//M+ - 储存器的值 = 显示屏的值+储存器的值      	
        {
        	if(c.getMemoryPlusFlag())
        		return ;
        	c.getMemory().setText(" M");
        	c.setMemoryValue(c.getMemoryValue() + Double.parseDouble(c.getDisplay().getText()));
        	c.setMemoryFlag(true);
        	c.setMemoryPlusFlag(true);
        }
		
        else if(source == c.b[30])//MS - 储存显示屏的值,并覆盖储存器原值
        {
        	c.getMemory().setText(" M");
        	c.setMemoryValue(Double.parseDouble(c.getDisplay().getText()));
        	c.setMemoryFlag(true);       	
        }
		
        else if(source == c.b[24])//MR - 显示储存器的值
        {
        	if(!c.getMemoryFlag())
        		return ;
        	c.getDisplay().setText(Double.toString(c.getMemoryValue()));  
        	c.setMemoryDisplayFlag(true);
        }
		
        else if(source == c.b[18])//MC - 重置储存器的值
        {
        	c.getMemory().setText("");
        	c.setMemoryValue(0);
        	c.setMemoryFlag(false);  
        	c.setMemoryDisplayFlag(false);
        }
		
	}//46个键监听完成									
	
	private void addNumberOrPoint()
	{
		if(c.getMemoryPlusFlag())
		{
			c.getDisplay().setText("");
			c.getStr1().setLength(0);
			c.setMemoryPlusFlag(false);
		}
		
		if(c.getRefreshFlag())//当运算结束时,再按下数字键要清空
		{
			if(!c.getNewFlag())
			{
				c.getStr1().setLength(0);
				c.getDisplay().setText("");
				if(source == c.b[39])//刷新后,第一个按下的是".",则先增加"0"
					c.getStr1().append(0);

			}
			else 
			{
				c.getStr2().setLength(0);
				c.getDisplay().setText("");
			}
			c.setRefreshFlag(false);
		}

		if(source == c.b[19])
			numberChar = '7';
		else if(source == c.b[20])
			numberChar = '8';
		else if(source == c.b[21])
			numberChar = '9';
		else if(source == c.b[25])
			numberChar = '4';
		else if(source == c.b[26])
			numberChar = '5';
		else if(source == c.b[27])
			numberChar = '6';
		else if(source == c.b[31])
			numberChar = '1';
		else if(source == c.b[32])
			numberChar = '2';
		else if(source == c.b[33])
			numberChar = '3';	
		else if(source == c.b[39])
			numberChar = '.';
		if(!c.getNewFlag())
		{
			if(c.getStr1().length() > 40 || c.getStr1().indexOf(".") != -1 && source == c.b[39])//长度小于40
				return ;
			c.getDisplay().setText(c.getStr1().toString() + numberChar);
			c.setStr1(c.getStr1().append(numberChar));
		}
		else
		{		
			if(c.getStr2().length() > 40 || c.getStr2().indexOf(".") != -1 && source == c.b[39])
				return ;