jdbc连接数据库

来源：互联网发布：mac虚拟机 360优化编辑：程序博客网时间：2024/05/21 23:47

import java.sql.*;public class TestJDBC{public static void main(String[] args){ResultSet rs=null;Statement stmt=null;Connection conn=null;        try{    Class.forName("com.mysql.jdbc.Driver");    conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/my_database","root","mima");    stmt=conn.createStatement();    rs=stmt.executeQuery("select * from student");    while(rs.next()){    System.out.println(rs.getInt("id"));    System.out.println(rs.getString("name"));    }    }catch(ClassNotFoundException e){    System.out.println("class not found");    e.printStackTrace();    }catch(SQLException e){    e.printStackTrace();    }finally{    try{        if(rs!=null){        rs.close();        rs=null;        }        if(stmt!=null){        stmt.close();        stmt.close();        }        if(conn!=null){        conn.close();        conn=null;        }    }catch(SQLException e){    e.printStackTrace();    }    }}}

package com.hibernate.model;import java.sql.*;public class TestJDBC {public static void main(String[] args) {if (args.length != 3) {System.out.println("paraments is not right");System.exit(-1);}int id = 0;try {id = Integer.parseInt(args[0]);} catch (NumberFormatException e) {System.out.println("id should be number format");System.exit(-1);}String name = args[1];String loc = args[2];Statement stmt = null;Connection conn = null;try {Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/my_database", "root","fangqiang");stmt = conn.createStatement();String sql = "insert into student values (" + id + ",'" + name+ ",'" + loc + "')";  //数值不加单引号，字符串加单引号System.out.println(sql);stmt.executeUpdate(sql);} catch (ClassNotFoundException e) {System.out.println("class not found");e.printStackTrace();} catch (SQLException e) {e.printStackTrace();} finally {try {if (stmt != null) {stmt.close();stmt.close();}if (conn != null) {conn.close();conn = null;}} catch (SQLException e) {e.printStackTrace();}}}}

package com.hibernate.model;import java.sql.*;public class TestJDBC {public static void main(String[] args) {if (args.length != 3) {System.out.println("paraments is not right");System.exit(-1);}int id = 0;try {id = Integer.parseInt(args[0]);} catch (NumberFormatException e) {System.out.println("id should be number format");System.exit(-1);}String name = args[1];String loc = args[2];PreparedStatement pstmt = null;Connection conn = null;try {Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/my_database", "root","fangqiang");pstmt = conn.prepareStatement("insert into student values (?,?,?)");pstmt.setInt(1, id);pstmt.setString(2, name);pstmt.setString(3, loc);pstmt.executeUpdate();} catch (ClassNotFoundException e) {System.out.println("class not found");e.printStackTrace();} catch (SQLException e) {e.printStackTrace();} finally {try {if (pstmt != null) {pstmt.close();pstmt.close();}if (conn != null) {conn.close();conn = null;}} catch (SQLException e) {e.printStackTrace();}}}}

0 0