package?caesar;

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

public?class?CaesarArithmetic?{
	public?static?void?main（String?args[]）?{
		//搭建基本窗口
		Jframe?f?=?new?Jframe（“凱撒密碼“）;
		final?JTextField?t1?=?new?JTextField（17）;
		final?JTextField?t2?=?new?JTextField（20）;
		final?JTextField?t3?=?new?JTextField（20）;
		final?JTextField?t4?=?new?JTextField（26）;
		JButton?b1?=?new?JButton（“密鑰（1~25）“）;
		JButton?b2?=?new?JButton（“加密“）;
		JButton?b3?=?new?JButton（“解密“）;
		//加密解密部分
		JPanel?p?=?new?JPanel（）;
		p.add（t1）;
		p.add（b1）;
		p.add（t2）;
		p.add（b2）;
		p.add（t3）;
		p.add（b3）;
		p.add（t4）;
		f.add（p）;
		//設置窗口大小及顯示
		f.setBounds（400?150?400?180）;
		f.setVisible（true）;
		
		//具體加密過程
		b2.addActionListener（new?ActionListener（）?{
			public?void?actionPerformed（ActionEvent?e）?{
				String?k?=?t1.getText（）;
				String?s?=?t2.getText（）;
				String?ss?=?new?String（）;
				int?kk?=?Integer.parseInt（k）;
				if（k?!=?null?&&?s?!=?null）?{
					Caesar?c1?=?new?Caesar（）;
					ss?=?c1.encrypt（s?kk）.toString（）;
					t4.setText（ss）;
				}
	????????}
	????}）;
		
		//具體解密過程
		b3.addActionListener（new?ActionListener（）?{
			public?void?actionPerformed（ActionEvent?e）?{
				String?k?=?t1.getText（）;
				String?s?=?t3.getText（）;
				String?ss?=?new?String（）;
				int?kk?=?Integer.parseInt（k）;
				if（k?!=?null?&&?s?!=?null）?{
					Caesar?c2?=?new?Caesar（）;
					ss?=?c2.decrypt（s?kk）.toString（）;
					t4.setText（ss）;
				}
	????????}
	????}）;
	}
}

//凱撒密碼算法
class?Caesar?{
	//加密算法
	public?StringBuffer?encrypt（String?s?int?k）?{
		int?i;
		StringBuffer?ss?=?new?StringBuffer（）;
		s?=?s.toLowerCase（）;
		int?l?=?s.length（）;
		char[]?s1?=?s.toCharArray（）;
		for（i=0;i			if（（s1[i]-97）?>=?0?&&?（s1[i]-97）?<=?25?&&?k?>=?1?&&?k?<=?25）?{
				ss.append（（char）（（s1[i]-97+k）%26+65））;
			}
			else?if（k??25?||?s?==?null）{
				JOptionPane.showMessageDialog（null?“內容或密鑰錯誤，請重新輸入！“）;
			}
		}
		return?ss;
	}
	//解密算法
	public?StringBuffer?decrypt（String?s?int?k）?{
		int?i;
		StringBuffer?ss?=?new?StringBuffer（）;
		s?=?s.toUpperCase（）;
		int?l?=?s.length（）;
		char[]?s1?=?s.toCharArray（）;
		for（i=0;i			if（（s1[i]-65）?>=?0?&&?（s1[i]-65）?<=?25?&&?k?>=?1?&&?k?<=?25）?{
				ss.append（（char）（（s1[i]-65-k+26）%26+97））;	
			}
			else?if（k??25?||?s?==?null）{
				JOptionPane.showMessageDialog（null?“內容或密鑰錯誤，請重新輸入！“）;
			}
		}
		return?ss;
	}
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\
?????文件?????????103??2017-12-16?09:36??3115005372_楊宇杰_信息安全\.git\COMMIT_EDITMSG
?????文件??????????23??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\HEAD
?????文件?????????227??2017-12-21?21:05??3115005372_楊宇杰_信息安全\.git\config
?????文件??????????73??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\description
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\hooks\
?????文件?????????478??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\applypatch-msg.sample
?????文件?????????896??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\commit-msg.sample
?????文件????????3505??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\fsmonitor-watchman.sample
?????文件?????????189??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\post-update.sample
?????文件?????????424??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\pre-applypatch.sample
?????文件????????1642??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\pre-commit.sample
?????文件????????1348??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\pre-push.sample
?????文件????????4898??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\pre-rebase.sample
?????文件?????????544??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\pre-receive.sample
?????文件????????1492??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\prepare-commit-msg.sample
?????文件????????3610??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\hooks\update.sample
?????文件????????3924??2017-12-21?21:05??3115005372_楊宇杰_信息安全\.git\index
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\info\
?????文件?????????240??2017-12-15?18:53??3115005372_楊宇杰_信息安全\.git\info\exclude
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\logs\
?????文件????????6345??2017-12-21?21:05??3115005372_楊宇杰_信息安全\.git\logs\HEAD
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\logs\refs\
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\logs\refs\heads\
?????文件????????6345??2017-12-21?21:05??3115005372_楊宇杰_信息安全\.git\logs\refs\heads\master
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\objects\
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\objects\00\
?????文件????????1746??2017-12-16?08:24??3115005372_楊宇杰_信息安全\.git\objects\00\d32c1f668681269d0c4b0090f4eee4450ad67a
?????文件?????????108??2017-12-16?00:16??3115005372_楊宇杰_信息安全\.git\objects\00\db951bfeb8c830c7627d8ffa3e6bfed494da23
?????目錄???????????0??2018-01-23?09:49??3115005372_楊宇杰_信息安全\.git\objects\02\
............此處省略847個文件信息