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String key=\ if(table.containsKey(key)) {

String m=\删除\年\月\日的日志吗?\ int ok=JOptionPane.showConfirmDialog(this,m,\询问\

JOptionPane.QUESTION_MESSAGE);

if(ok==JOptionPane.YES_OPTION) { try {

FileInputStream inOne=new FileInputStream(file); ObjectInputStream inTwo=new ObjectInputStream(inOne); table=(Hashtable)inTwo.readObject(); inOne.close(); inTwo.close(); table.remove(key);

FileOutputStream out=new FileOutputStream(file); ObjectOutputStream objectOut=new ObjectOutputStream(out); objectOut.writeObject(table); objectOut.close(); out.close();

text.setText(null); }

catch(Exception ee) { } } } else {

String m=\年\月\无日志记录\ JOptionPane.showMessageDialog(this,m,\提示\ARNING_MESSAGE); }

//删除数据库记录

DBAccess db = new DBAccess(); if(db.createConn()) {

// 根据name组成删除SQL，执行删除

String sql = \

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db.update(sql); db.closeStm(); db.closeConn(); } } }

//提取当前的年月日时分秒，时钟 package javaapplication13;

import java.awt.Canvas; import java.awt.Color; import java.awt.Font; import java.awt.Graphics;

import java.text.SimpleDateFormat; import java.util.Calendar;

class Clock extends Canvas implements Runnable{

private static final long serialVersionUID = 3660124045489727166L; CalendarPad mf;

Thread t;//Multi-Thread(斜体) String time;

public Clock(CalendarPad mf){ this.mf=mf; setSize(280,40); setBackground(Color.white); t=new Thread(this); //实例化线程 t.start(); //调用线程 }

public void run(){ while(true){ try{

Thread.sleep(1000); //休眠1秒钟 }catch(InterruptedException e){ System.out.println(\异常\ }

this.repaint(100); //重画屏幕 } }

/*public abstract void drawString(AttributedCharacterIterator iterator, int x,

int y)依据 TextAttribute 类的规范应用指定

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迭代器的属性，呈现迭代器的文本。

最左侧字符的基线位于此图形上下文坐标系的 (x, y) 位置处。 */

//对paint函数进行重写(多态) public void paint(Graphics g){ Font f=new Font(\宋体\

SimpleDateFormat SDF=new SimpleDateFormat(\ yyyy'年'MM'月'dd'日'HH:mm:ss\格式化时间显示类型 Calendar now=Calendar.getInstance(); time=SDF.format(now.getTime()); //得到当前日期和时间 g.setFont(f); g.setColor(Color.RED); g.drawString(time,25,25); } }

//用Oracle的方式连接数据库 package javaapplication13;

import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet;

import java.sql.SQLException; import java.sql.Statement;

//JDBC 数据库连接，直连，利用Oracle(双下划线) public class DBAccess { public static String drv = \ public static String url = \ public static String usr = \ public static String pwd = \ private Connection conn = null; private Statement stm = null; private ResultSet rs = null; public boolean createConn() { boolean b = false; try { Class.forName(drv).newInstance(); conn = DriverManager.getConnection(url, usr, pwd); b = true; } catch (SQLException e) {

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}

} catch (ClassNotFoundException e) { } catch (InstantiationException e) { } catch (IllegalAccessException e) { }

return b;

public boolean update(String sql) { boolean b = false; try { stm = conn.createStatement(); stm.execute(sql); b = true; } catch (Exception e) { System.out.println(e.toString()); } return b; }

public void query(String sql) { try { stm = conn.createStatement(); rs = stm.executeQuery(sql); } catch (Exception e) { } }

public boolean next() { boolean b = false; try { if(rs.next())b = true; } catch (Exception e) { } return b; }

public String getValue(String field) { String value = \ try { if(rs!=null)value = rs.getString(field); } catch (Exception e) { e.printStackTrace(); } if (value == null) value = \