package?com.ares.util;

import?java.awt.*;
import?java.awt.event.*;
import?javax.swing.*;

/**
?*?Calculator類，實現計算器界面版
?*?@author?Ares
?*?@version?1.0
?*?@see?GBC.java
?*/
public?class?Calculator?implements?ActionListener{
	/**用來標識所有按鍵*/
	final?String[]?KEYS?=?{?“CE“?“C“?“←“?“÷“?“7“?“8“?“9“?“ד?“4““5“?“6“?“-“?“1“?“2“?“3“?“+“?“0“?“.“?“=“?};
	/**將所有按鈕用Button數組實現*/
	JButton[]?keys?=?new?JButton[KEYS.length];
	/**用來顯示結果區域*/
	JTextField?resultText?=?new?JTextField（“0“）;
	/**標志按的是表達式第一個數字，還是運算符后的第一個數字*/
	private?boolean?firstDigit?=?true;???
	/**中間結果*/
	private?double?resultNum?=?0.0;?
	/**當前運算的運算符??*/
????private?String?operator?=?“=“;???
????/**判斷操作是否合法*/
	private?boolean?operateValidFlag?=?true;?
	
	/**
	?*?向面板中添加組件
	?*?@param?pane?用來添加組件的面板
	?*/
	public?void?addComponentsToPane（Container?pane）?{
		GridBagLayout?layout?=?new?GridBagLayout（）;
		pane.setLayout（layout）;
		resultText.setFont（new?Font（“Century?Schoolbook“?Font.PLAIN?14））;
		resultText.setEditable（false）;
		resultText.setHorizontalAlignment（SwingConstants.RIGHT）;
		pane.add（resultTextnew?GBC（0?0?4?1）.setIpad（400?50）.setWeight（0.5?0.5）.setFill（GridBagConstraints.BOTH））;
		for?（int?i?=?0;?i?			keys[i]?=?new?JButton（KEYS[i]）;
			if（i?==?keys.length-3）{
				pane.add（keys[i]new?GBC（i?%?4?i?/?4?+?121）.setIpad（0?12）.setInsets（1）.setFill（GridBagConstraints.BOTH）.setWeight（0.5?0.5））;
			}else?if?（i?==?keys.length-2?||?i?==?keys.length-1）?{
				pane.add（keys[i]new?GBC（i?%?4+1?i?/?4?+?1）.setIpad（0?12）.setInsets（1）.setFill（GridBagConstraints.BOTH）.setWeight（0.5?0.5））;
			}else?{
				pane.add（keys[i]?new?GBC（i?%?4?i?/?4?+?1）.setIpad（0?12）.setInsets（1）.setFill（GridBagConstraints.BOTH）.setWeight（0.5?0.5））;
			}
		}
		for?（int?i?=?0;?i?????????????keys[i].addActionListener（this）;??
????????}?
	}
	
	/**
	?*?創建和顯示界面
	?*/
	public?void?createAndShowGUI（）?{
		Jframe?frame?=?new?Jframe（“Calculator“）;
		frame.setDefaultCloseOperation（Jframe.EXIT_ON_CLOSE）;
		addComponentsToPane（frame.getContentPane（））;
		frame.pack（）;
		frame.setVisible（true）;
	}
	
	/**
	?*?執行點擊按鈕出發的動作
	?*?@override?
	?*?@see?java.awt.event.actionPerformed
	?*/
	public?void?actionPerformed（ActionEvent?e）?{
		String?label?=?e.getActionCommand（）;
		if（label.equals（KEYS[0]））{
			resultText.setText（“0“）;
		}else?if?（label.equals（KEYS[1]））?{
			handleC（）;
		}else?if?（label.equals（KEYS[2]））?{
			handleBackspace（）;
		}else?if?（“0123456789.“.indexOf（label）?>=?0）?{
			handleNumber（label）;
		}else{
			handleOperator（label）;
		}
	}

	/**
	?*?處理撤銷建
	?*/
	private?void?handleBackspace（）?{??
????????String?text?=?resultText.getText（）;??
????????int?i?=?text.length（）;??
????????if?（i?>?0）?{??
????????????text?=?text.substring（0?i?-?1）;??
????????????if?（text.length（）?==?0）?{??
????????????????resultText.setText（“0“）;??
????????????????firstDigit?=?true;??
????????????????operator?

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2015-05-24?15:04??Calculator\
?????文件?????????232??2015-05-19?14:29??Calculator\.classpath
?????文件?????????386??2015-05-19?14:29??Calculator\.project
?????目錄???????????0??2015-06-12?11:13??Calculator\bin\
?????目錄???????????0??2015-06-12?11:13??Calculator\bin\com\
?????目錄???????????0??2015-06-12?11:13??Calculator\bin\com\ares\
?????目錄???????????0??2015-06-25?21:44??Calculator\bin\com\ares\util\
?????文件?????????554??2015-06-12?11:13??Calculator\bin\com\ares\util\Calculator$1.class
?????文件????????5300??2015-06-12?11:13??Calculator\bin\com\ares\util\Calculator.class
?????文件????????1499??2015-06-12?11:13??Calculator\bin\com\ares\util\GBC.class
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\
?????文件?????????748??2015-05-24?20:45??Calculator\doc\allclasses-frame.html
?????文件?????????708??2015-05-24?20:45??Calculator\doc\allclasses-noframe.html
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\com\
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\com\ares\
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\com\ares\util\
?????文件???????11422??2015-05-24?20:45??Calculator\doc\com\ares\util\Calculator.html
?????文件???????16905??2015-05-24?20:45??Calculator\doc\com\ares\util\GBC.html
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\com\ares\util\class-use\
?????文件????????4110??2015-05-24?20:45??Calculator\doc\com\ares\util\class-use\Calculator.html
?????文件????????7453??2015-05-24?20:45??Calculator\doc\com\ares\util\class-use\GBC.html
?????文件?????????865??2015-05-24?20:45??Calculator\doc\com\ares\util\package-frame.html
?????文件????????4704??2015-05-24?20:45??Calculator\doc\com\ares\util\package-summary.html
?????文件????????4310??2015-05-24?20:45??Calculator\doc\com\ares\util\package-tree.html
?????文件????????4602??2015-05-24?20:45??Calculator\doc\com\ares\util\package-use.html
?????文件????????3586??2015-05-24?20:45??Calculator\doc\constant-values.html
?????文件????????3574??2015-05-24?20:45??Calculator\doc\deprecated-list.html
?????文件????????7208??2015-05-24?20:45??Calculator\doc\help-doc.html
?????目錄???????????0??2015-05-24?15:04??Calculator\doc\index-files\
?????文件????????4655??2015-05-24?20:45??Calculator\doc\index-files\index-1.html
?????文件????????4972??2015-05-24?20:45??Calculator\doc\index-files\index-2.html
............此處省略15個文件信息