从网络数据库中下载数据，备份到文本文件中

<script type="text/javascript" src="http://pagead2.googlesyndication.com/pagead/show_ads.js"> </script> import java.io.*; import java.awt.*; import java.awt.event.*; import java.util.*; import java.net.URL; import java.sql.*; import java.net.*; class Window extends Frame implements ActionListener { TextArea text; Panel panel; TextField year; TextField qihao; StringBuffer text1; Button button1; BufferedWriter out; ResultSet rs; Connection cn; String fname; String[] fenbu; String qisu; String yearnum; Choice choice1; int fenbusu; Window() { super("test!"); setLayout(new BorderLayout()); setBackground(Color.cyan); setBounds(150,150,300,120); setVisible(true); text=new TextArea(); button1=new Button("确定"); year=new TextField("2003",5); qihao=new TextField(5); panel=new Panel(); panel.add(new Label("选择分部：")); choice1=new Choice(); choice1.addItem("北京"); choice1.addItem("成都"); choice1.addItem("上海"); choice1.addItem("广州"); choice1.addItem("全部"); panel.add(choice1); panel.add(new Label("输入年份：")); panel.add(year); panel.add(new Label("输入期号：")); panel.add(qihao); panel.add(button1); add("North",panel); add(text,"Center"); button1.addActionListener(this); addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { setVisible(false); System.exit(0); } }); } public void actionPerformed(ActionEvent e) { qisu=qihao.getText().trim(); yearnum=year.getText().trim(); if(e.getSource()==button1) { if(choice1.getSelectedIndex()==0) { fname=("beijing.txt"); text.setText("beginning!!!!"); text1=new StringBuffer(); try{ ListData("lbeijing"); ListData("lheilongjiang"); ListData("ljilin"); ListData("lhenan"); ListData("lliaoning"); text1=new StringBuffer(); cn.close(); } catch(SQLException eee){} catch(IOException ie){} text.setText("finished!!!!!"); } else if(choice1.getSelectedIndex()==1) { fname=("chendu.txt"); text.setText("beginning!!!!!!"); text1=new StringBuffer(); try{ ListData("lchongqing"); ListData("lhubei"); ListData("lsichuan"); ListData("lxinjiang"); ListData("lguizhou"); ListData("lyunnan"); ListData("lshanxiq"); ListData("lgansu"); ListData("lshanxij"); text1=new StringBuffer(); cn.close(); } catch(SQLException eee){} catch(IOException ie){} text.setText("finished!!!!!!!!!!"); } else if(choice1.getSelectedIndex()==2) { text1=new StringBuffer(); text.setText("beginning!!!!!!!!!"); fname=("shanghai.txt"); try { ListData("lshanghai"); ListData("ljiangsu"); ListData("lshandong"); ListData("lzhejiang"); ListData("lanhui"); text1=new StringBuffer(); cn.close(); } catch(SQLException eee){} catch(IOException ie){} text.setText("finished!!!!!!!!"); } else if(choice1.getSelectedIndex()==3) { text1=new StringBuffer(); text.setText("beginning!!!!!!!!!"); fname=("guangdong.txt"); try{ ListData("lguangdong"); ListData("lshenzhen"); ListData("lfujian"); ListData("lguangxi"); ListData("lhunan"); text1=new StringBuffer(); cn.close(); } catch(SQLException eee){} catch(IOException ie){} text.setText("finished!!!!!!!!!"); } else if(choice1.getSelectedIndex()==4) { text1=new StringBuffer(); text.setText("beginning!!!!!!!!!"); fname=(qisu ".txt"); try{ ListData("lbeijing"); ListData("lheilongjiang"); ListData("ljilin"); ListData("lhenan"); ListData("lliaoning"); ListData("lchongqing"); ListData("lhubei"); ListData("lsichuan"); ListData("lxinjiang"); ListData("lguizhou"); ListData("lyunnan"); ListData("lshanxiq"); ListData("lgansu"); ListData("lshanxij"); ListData("lshanghai"); ListData("ljiangsu"); ListData("lshandong"); ListData("lzhejiang"); ListData("lanhui"); ListData("lguangdong"); ListData("lshenzhen"); ListData("lfujian"); ListData("lguangxi"); ListData("lhunan"); text1=new StringBuffer(); cn.close(); } catch(SQLException eee){} catch(IOException ie){} text.setText("finished!!!!!!!!!"); } } } public void ListData(String fb) throws SQLException,IOException { String lfb=fb; String txt=new String(""); try{ Class.forName("org.gjt.mm.mysql.Driver"); }catch(ClassNotFoundException e){} cn=DriverManager.getConnection("jdbc:mysql://172.143.41.216:3306/fxbdb","username","password"); Statement st=cn.createStatement(); rs=st.executeQuery("select * from " lfb " where issuenumber=" qisu " and issueyear=" yearnum); while(rs.next()){ text1.append(rs.getString(2) "|" rs.getString(3) "|" rs.getString(4) "|" rs.getString(5) "|" rs.getString(6) "|" rs.getString(7) "|" rs.getString(8) "|" rs.getString(9) "|" rs.getString(10) "|" rs.getString(11) "|" rs.getString(12) "|" rs.getString(13) "|" rs.getString(14) "|" rs.getString(18) "|" "/n"); } txt=text1.toString(); try{ out=new BufferedWriter(new FileWriter(fname)); } catch(FileNotFoundException p) {} try{ out.write(txt,0,txt.length()); out.flush(); } catch(IOException exp) { System.out.println("have problem!"); } } } public class DownData { public static void main(String args[]) { Window window=new Window(); window.pack(); } }