JDBC 工具类优化

package com.lin;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ResourceBundle;

/**
 * jdbc 工具类
 */
public class jdbcUtil {
    private static String driver ;
    private static String jdbcUrl ;
    private static String userName ;
    private static String password ;

    static {
        //读取properties文件
        ResourceBundle jdbc = ResourceBundle.getBundle("jdbc");
        driver = jdbc.getString("driver");
        jdbcUrl =jdbc.getString("jdbcUrl");
        userName=jdbc.getString("userName");
        password=jdbc.getString("userName");

        try {
            Class.forName("driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    //获取Connection 对象
    public static Connection getConnection() {
        Connection connection = null;
        try {
            connection = DriverManager.getConnection(jdbcUrl, userName, password);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return connection;
    }

    //关闭Statement
    public static void closeStatement(Statement statement) {
        if (statement != null) {
            try {
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    //关闭Connection
    public static void closeConnection(Connection connection) {
        if (connection != null) {
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    //关闭所有资源
    public static void closeResource(Statement statement, Connection connection) {
        closeStatement(statement);
        closeConnection(connection);
    }

}

package com.lin;

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

/**
 * 使用工具类进行jdbc操作
 */
public class jdbcTest1 {


        //向Departments 表中添加一个数据
        public void insertDepartments(String department_name,int location_id) {
            Connection connection = null;
            Statement statement = null;
            try {
                //1.注册驱动
                connection = jdbcUtil.getConnection();
                //编辑sql语句
                String sql = "insert into departments values(default,'" + department_name + "','" + location_id + "')";
                //创建Statement对象用于发送数据
                statement = connection.createStatement();
                int flag = statement.executeUpdate(sql);
                System.out.println(flag);

            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                jdbcUtil.closeStatement(statement);
                jdbcUtil.closeConnection(connection);
            }



        }

        //更新departments 表中的department_di 为6 的数据 部门名称修改为java研发部 location_id改为6
        public void updateDepartments( String department_id,String department_name, int location_id){
            Connection connection = null;
            Statement statement = null;

            try {
              connection= jdbcUtil.getConnection();
                //创建Statement对象用于发送数据
                statement =connection.createStatement();
                //创建SQL语句
                String sql =  "update departments d set d.department_name = '"+department_name+"',d.location_id = "+location_id+" where d.department_id ="+department_id;
                int falg = statement.executeUpdate(sql);
                if (falg ==1){
                    System.out.println("修改成功");
                }else {
                    System.out.println("修改失败");
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {

                jdbcUtil.closeResource(statement,connection);
            }


        }


        public static void main(String[] args) {
            com.lin.jdbcTest jdbcTest = new com.lin.jdbcTest();
            jdbcTest.insertDepartments("采购部",12);
          //  jdbcTest.updateDepartments("7","推广销售部",7);

        }
 }