一、JDBC的使用步骤

1、注册数据库的驱动                 

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

 2、通过DriverManager获取数据库连接      

 //jdbc:subprotocol/subname
String url = "jdbc:mysql://127.0.0.1:3306/dbName?useUnicode=true&characterEncoding=utf8"; 
String user = "xxxx";
String password = "xxxx";
Connection connection = DriverManager.getConnection(url, user, password);

3、通过Connection对象获取Statement对象   

Statement state = connection.createStatement();

4、使用Statement执行SQL语句

 //return  java.sql interface
ResautSet rs =state.executeQuery(sql);

5、操作ResultSet结果集                 

String order=rs.getString("order");

6、回收数据库资源                  

if (state != null) {
    state.close();
}
state = null;

package cn.itcast.example01;


import java.sql.*;

/**
 * @author wangyue
 * @version 1.0
 * @date 2019/7/8 10:08
 * @describe: JDBC使用的步骤
 * 1. 注册数据库的驱动   Class.forName("com.mysql.jdbc.Driver");
 * 2.通过DriverManager获取数据库连接        connection = DriverManager.getConnection(url, user, password);
 * 3.通过Connection对象获取Statement对象    state = connection.createStatement();
 * 4.使用Statement执行SQL语句              rs =state.executeQuery(sql);
 * 5. 操作ResultSet结果集                  String order=rs.getString("order");
 * 6.回收数据库资源                        if (state != null) {
 *                                          state.close();
 *                                       }
 *                                       state = null;
 */
public class Example01 {
    public static void main(String[] args) throws SQLException {
        Connection connection = null;
        Statement state = null;
        ResultSet rs = null;
        try {
            //1. 注册数据库的驱动
            Class.forName("com.mysql.jdbc.Driver");
//            2.通过DriverManager获取数据库连接
            String url = "jdbc:mysql://127.0.0.1:3306/dbName?useUnicode=true&characterEncoding=utf8";  //jdbc:subprotocol/subname
            String user = "xxx";
            String password = "xxxxxx";
            connection = DriverManager.getConnection(url, user, password);
            //3.通过Connection对象获取Statement对象
            state = connection.createStatement();
            //4.使用Statement执行SQL语句
            String sql = "select * from pro_order";
            rs = state.executeQuery(sql); //return  java.sql interface

            //5. 操作ResultSet结果集
            while (rs.next()) {
                String lineName = rs.getString("lineName");
                String issueStatus = rs.getString("issueStatus");
                String order = rs.getString("order");
                String orderType = rs.getString("orderType");
                Date planStartTime = rs.getDate("planStartTime");
                System.out.println(lineName + " | " + issueStatus + " | " + order + " | " + orderType + " | " + planStartTime);

            }
            
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } finally {
            //6.回收数据库资源
            if (connection != null) {
                connection.close();
            }
            connection = null;

            if (state != null) {
                state.close();
            }
            state = null;

            if (rs != null) {
                rs.close();
            }
            rs = null;

        }
    }
}



输出
产线1 | 已下发 | WO01020301 | 正常 | 2019-03-01
产线1 | 已下发 | WO19020101 | 待再加工 | 2019-02-07
产线1 | 未下发 | WO19030101 | 待再加工 | 2019-03-02
产线1 | 已下发 | WO19030201 | 待再加工 | 2019-03-09
产线1 | 未下发 | WO19030301 | 正常 | 2019-03-21
产线1 | 未下发 | WO19032801 | 正常 | 2019-03-29
产线1 | 已下发 | WO19032901 | 正常 | 2019-03-30
产线1 | 未下发 | WO19042801 | 正常 | 2019-03-29
产线1 | 未下发 | WO19050101 | 待再加工 | 2019-03-02
产线1 | 未下发 | WO19050102 | 待再加工 | 2019-03-02
产线1 | 已下发 | WO19052301 | 正常 | 2019-06-01
产线1 | 未下发 | WO19052801 | 正常 | 2019-03-29