当前位置:Gxlcms > 数据库问题 > JDBC开发步骤

JDBC开发步骤

时间:2021-07-01 10:21:17 帮助过:8人阅读

java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.sql.Statement; public class Demo01 { public static void main(String[] args) throws ClassNotFoundException, SQLException { //1.注册驱动 Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库(获取连接对象) String url="jdbc:mysql://127.0.0.1:3306/java 1018?characterEncoding=UTF-8"; String user="root"; String password="123456"; Connection con = DriverManager.getConnection(url,user,password); //System.out.println(con); //3.获得语句执行对象 Statement sta = con.createStatement(); String sql = "insert into sort(sname) values(‘小裙子‘)"; //4.执行sql语句 int row= sta.executeUpdate(sql); System.out.println(row); //5.释放资源(先开的后关) sta.close(); } }

 2.try……catch……

package com.oracle.demo01;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;



public class Demo05 {
    public static void main(String[] args) {
        PreparedStatement pst=null;
        Connection con=null;
        //1.注册驱动
        try {
            Class.forName("com.mysql.jdbc.Driver");
            //2.获取连接对象
            String url="jdbc:mysql://127.0.0.1:3306/java 1018?characterEncoding=UTF-8";
            String user="root";
            String password="123456";
            con = DriverManager.getConnection(url,user,password);
            //3.获取语句执行对象
            String sql="update sort set sname=? where sid=?";
            pst=con.prepareStatement(sql);
            pst.setInt(2, 5);
            pst.setString(1, "小裙子");
            //4.执行sql语句
            int row =pst.executeUpdate();
            System.out.println(row);
        } catch (ClassNotFoundException | SQLException e) {
            
            e.printStackTrace();
        }finally {
            //5.释放资源
            try {
                pst.close();
                con.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
    }
}

3.封装为静态类

package com.oracle.demo01;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class JDBCUtils {
    //获取connection对象的方法
    public static Connection getconn() {
        //1.注册驱动
        Connection conn=null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            //2.连接数据库(获取连接对象)
            String url="jdbc:mysql://127.0.0.1:3306/java 1018?characterEncoding=UTF-8";
            String user="root";
            String password="123456";
            conn = DriverManager.getConnection(url,user,password);
        } catch (ClassNotFoundException | SQLException e) {
            
            e.printStackTrace();
        }
        return conn;
        
    }
}

4.静态类调用

package com.oracle.demo01;

import java.sql.PreparedStatement;
import java.sql.SQLException;

public class Demo06 {
    public static void main(String[] args) {
        String sql="insert into sort values(?,?)";
        
        PreparedStatement pst=null;
        try {
            pst=JDBCUtils.getconn().prepareStatement(sql);
            pst.setInt(1, 4);
            pst.setString(2, "小裙子");
            
            int row =pst.executeUpdate();
            System.out.println(row);
        } catch (SQLException e) {
            
            e.printStackTrace();
        }finally {
            try {
                pst.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
    }
  
    //增、删、改 释放资源
    public static void close(Statement pst,Connection conn) {
        if (pst!=null) {
            try {
                pst.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
        if (conn!=null) {
            try {
                conn.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
    }
    //查询 释放资源
    public static void close(ResultSet rs,Statement pst,Connection conn) {
        if (rs!=null) {
            try {
                rs.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
        if (pst!=null) {
            try {
                pst.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
        if (conn!=null) {
            try {
                conn.close();
            } catch (SQLException e) {
                
                e.printStackTrace();
            }
        }
    }
}

.

JDBC开发步骤

标签:code   调用   trace   catch   upd   res   acl   drive   into   

人气教程排行