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package db;
 
import java.io.File;
import java.io.IOException;
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 
import java.sql.SQLException; 
import java.sql.Statement; 
import java.util.Scanner;
 
public class jdbcmysql2
{ 
  private Connection con = null; //Database objects 
  //連接object 
  private Statement stat = null; 
  //執行,傳入之sql為完整字串 
  private ResultSet rs = null; 
  //結果集 
  private PreparedStatement pst = null; 
  //執行,傳入之sql為預儲之字申,需要傳入變數之位置 
  //先利用?來做標示 
  
  private String dropdbSQL = "DROP TABLE udp2 "; 
  
  private String createdbSQL = "CREATE TABLE udp2 ("+"item VARCHAR(15)"+",lifetime VARCHAR(255)"+",count INTEGER)"; 
  
  private String insertdbSQL = "insert into udp2(item,lifetime,count) VALUES(?,?,?) from udp2 "; 
  
  private String selectSQL = "select * from udp2 "; 
  
  public jdbcmysql2() 
  { 
    try 
    { 
      Class.forName("com.mysql.jdbc.Driver"); 
      //註冊driver 
      con = DriverManager.getConnection( 
          "jdbc:mysql://localhost/udp?useUnicode=true&characterEncoding=Big5","root","test"); 
      //取得connection
 
      //jdbc:mysql://localhost/test?useUnicode=true&characterEncoding=Big5
      //localhost是主機名,test是database名
      //useUnicode=true&characterEncoding=Big5使用的編碼 
      
    } 
    catch(ClassNotFoundException e) 
    { 
      System.out.println("DriverClassNotFound :"+e.toString()); 
    }//有可能會產生sqlexception 
    catch(SQLException x) 
    { 
      System.out.println("Exception :"+x.toString()); 
    } 
    
  } 
  //建立table的方式 
  //可以看看Statement的使用方式 
  public void createTable() 
  { 
    try 
    { 
      stat = con.createStatement(); 
      stat.executeUpdate(createdbSQL); 
    } 
    catch(SQLException e) 
    { 
      System.out.println("CreateDB Exception :" + e.toString()); 
    } 
    finally 
    { 
      Close(); 
    } 
  } 
  //新增資料 
  //可以看看PrepareStatement的使用方式 
  public void insertTable(String item, String lifetime, String count) 
  { 
    try 
    { 
      pst = con.prepareStatement(insertdbSQL); 
      
      pst.setString(0, item); 
      pst.setString(1, lifetime); 
      pst.setString(2, count); 
      pst.executeUpdate(); 
    } 
    catch(SQLException e) 
    { 
      System.out.println("InsertDB Exception :" + e.toString()); 
    } 
    finally 
    { 
      Close(); 
    } 
  } 
  //刪除Table, 
  //跟建立table很像 
  public void dropTable() 
  { 
    try 
    { 
      stat = con.createStatement(); 
      stat.executeUpdate(dropdbSQL); 
    } 
    catch(SQLException e) 
    { 
      System.out.println("DropDB Exception :" + e.toString()); 
    } 
    finally 
    { 
      Close(); 
    } 
  } 
  //查詢資料 
  //可以看看回傳結果集及取得資料方式 
  public void SelectTable() 
  { 
    try 
    { 
      stat = con.createStatement(); 
      rs = stat.executeQuery(selectSQL); 
      System.out.println("Item\t\tLifetime\t\tCount"); 
      while(rs.next()) 
      { 
        System.out.println(rs.getInt("item")+"\t\t"+ 
            rs.getString("lifetime")+"\t\t"+ rs.getString("count")); 
      } 
    } 
    catch(SQLException e) 
    { 
      System.out.println("DropDB Exception :" + e.toString()); 
    } 
    finally 
    { 
      Close(); 
    } 
  } 
  //完整使用完資料庫後,記得要關閉所有Object 
  //否則在等待Timeout時,可能會有Connection poor的狀況 
  private void Close() 
  { 
    try 
    { 
      if(rs!=null) 
      { 
        rs.close(); 
        rs = null; 
      } 
      if(stat!=null) 
      { 
        stat.close(); 
        stat = null; 
      } 
      if(pst!=null) 
      { 
        pst.close(); 
        pst = null; 
      } 
    } 
    catch(SQLException e) 
    { 
      System.out.println("Close Exception :" + e.toString()); 
    } 
  } 
  
 
  public static void main(String[] args) throws IOException 
  { 
    //測看看是否正常 
    jdbcmysql2 test = new jdbcmysql2(); 
    test.dropTable(); 
    test.createTable(); 
    
    Scanner scan = new Scanner(new File("test.txt"));
    while (scan.hasNext())
    {
      String perLine = scan.nextLine().trim();
      String[] dataAry = perLine.split(", ");
      test.insertTable(dataAry[0], dataAry[1], dataAry[2]); 
      test.SelectTable();
        
    }  
  } 
}

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pst.setString(1, item); 
pst.setString(2, lifetime); 
pst.setString(3, count); 

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public void insertTable(String item, String lifetime, int count) 
  { 
    try 
    { 
      pst = con.prepareStatement(insertdbSQL); 
      
      pst.setString(1, item); 
      pst.setString(2, lifetime); 
      pst.setInt(3, count); 
      pst.executeUpdate(); 
    } 
    catch(SQLException e) 
    { 
      System.out.println("InsertDB Exception :" + e.toString()); 
    } 
    finally 
    { 
      Close(); 
    } 
  }