实现加载驱动、得到数据库对象、关闭资源的代码复用，将代码提取到相应的工具包里边。优化程序

实现加载驱动、得到数据库对象、关闭资源的代码复用，将代码提取到相应的工具包里边。优化程序

工具包

package com.xxx;

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

/**
 * 工具类
 * 
 */

public class Connectiontools {

    public static Connection getConn() {
        Connection conn = null;
        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            String url = "jdbc:sqlserver://localhost:1433;databaseName=test";
            String username = "zheng";
            String pwd = "123";
            conn = DriverManager.getConnection(url, username, pwd);
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return conn;
    }

    // 关闭修改操作
    public static void close(Statement stmt, Connection conn) {
        try {
            if (stmt != null) {
                stmt.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    // 关闭插入、插入等操作
    public static void close(Statement stmt, ResultSet rs, Connection conn) {
        try {
            if (stmt != null) {
                stmt.close();
            }
            if (rs != null) {
                rs.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

    }

}

实现的操作

package com.xxx;

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

public class StatementDemo1 {

    private Connection conn = null;
    private Statement stmt = null;
    private ResultSet result = null;

    // 查询员工信息
    public void query() {
        // 1、加载驱动
        try {
            conn = Connectiontools.getConn();
            stmt = conn.createStatement();
            // 查询信息
            String selectstr = "select *from info";
            result = stmt.executeQuery(selectstr);
            // 4、处理结果集
            System.out.println("员工编号：\t员工姓名：\t工作：");
            while (result.next()) {
                System.out.println(result.getString("id") + "\t" + result.getString("name") + "\t" + "\t"
                        + result.getString("job"));
            }

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            // 释放资源
            Connectiontools.close(stmt, result, conn);
        }

    }

    // 修改信息
    public void update() {
        try {
            // 1、加载驱动
            conn = Connectiontools.getConn();
            // 2、创建statement
            stmt = conn.createStatement();
            // 3、创建sql语句
            String updatestr = "update info set job='教授 ' where id='001'";
            int result = stmt.executeUpdate(updatestr);
            // 4、处理结果集
            if (result > 0) {
                System.out.println("更新成功！！！");
            } else {
                System.out.println("更新失败！！！");
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            Connectiontools.close(stmt, conn);
        }

    }

    public static void main(String[] args) {
        StatementDemo1 c = new StatementDemo1();
        c.query();
    }

}