java jdbc----mysql的select、insert、update、delete

//-----------------------------------select----------------------------------

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

public class TestSelect{

 public static void main(String[] args) {

  Connection conn = null;

  Statement stmt = null;

  ResultSet rs = null;

  try {

   Class.forName("com.mysql.jdbc.Driver");

   conn = DriverManager

     .getConnection("jdbc:mySql://localhost/mydata?user=root&password=root");

   stmt = conn.createStatement();

   String sql = "select * from article";

   rs = stmt.executeQuery(sql);

   while (rs.next()) {

    System.out.println(rs.getInt("id"));

    System.out.println(rs.getString("title"));

   }

  } catch (Exception e) {

   e.printStackTrace();

  } finally {

   try {

    if (rs != null) {

     rs.close();

     rs = null;

    }

    if (stmt != null) {

     stmt.close();

     stmt = null;

    }

    if (conn != null) {

     conn.close();

     conn = null;

    }

   } catch (SQLException e) {

    e.printStackTrace();

   }

  }

 }

}

//-------------------------insert--------------------------

import java.sql.*;

public class TestInsert {

 public static void main(String[] args) {

  Connection conn = null;

  Statement stmt = null;

  try {

   Class.forName("com.mysql.jdbc.Driver");

   conn = DriverManager

     .getConnection("jdbc:mysql://localhost/mydata?user=root&password=root");

   stmt = conn.createStatement();

   String sql = "insert into article(title) values('fff')";

   stmt.executeUpdate(sql);

  } catch (Exception e) {

   e.printStackTrace();

  } finally {

   try {

    stmt.close();

    conn.close();

   } catch (SQLException e) {

    e.printStackTrace();

   }

  }

 }

}

//-----------------------------update----------------------------

import java.sql.*;

public class TestUpdate {

 public static void main(String[]args){

  Connection conn = null;

  Statement stmt = null;

  try{

   Class.forName("com.mysql.jdbc.Driver");

   conn = DriverManager.getConnection("jdbc:mysql://localhost/mydata?user=root&password=root");

   stmt = conn.createStatement();

   String sql = "update article set title ='ggg' where id=5";

   stmt.executeUpdate(sql);

  }catch(Exception e){

   e.printStackTrace();

  }finally{

   try {

    stmt.close();

    conn.close();

   } catch (SQLException e) {

    e.printStackTrace();

   }

  }

 }

}

//---------------------------delete-------------------------

import java.sql.*;

public class TestDelete {

 public static void main(String[]args){

  Connection conn = null;

  Statement stmt = null;

  try{

   Class.forName("com.mysql.jdbc.Driver");

   conn = DriverManager.getConnection("jdbc:mysql://localhost/mydata?user=root&password=root");

   stmt = conn.createStatement();

   stmt.execute("delete from article where title='fff'");

   

  }catch(Exception e){

   e.printStackTrace();

  }finally{

   try {

    conn.close();

    stmt.close();

   } catch (SQLException e) {

    e.printStackTrace();

   }

  }

  

 }

}