- package com.hanchao.jdbc;
- import java.sql.Connection;
- import java.sql.DriverManager;
- import java.sql.PreparedStatement;
- import java.sql.ResultSet;
- /**
- * jdbc学习总结二
- * @author hanlw
- * 2012-07-09
- */
- public class TestJdbcNew {
- /**
- * 上一篇文章,我们对JDBC有了初步的了解,并且知道了如何使用JDBC了。
- * 但是,那只是JDBC的了解性操作实例。实际开发中,我们是不能那么玩的!!
- *
- * ★下面我们学习一下:JDBC的占位符的使用,以后写程序建议都要这么玩的!!
- *
- * 注意事项:我们的异常应该捕获;而不是抛出来啊!!
- *
- * SQLException是非运行时异常,必须要捕获或者向上抛出!!★
- */
- public static void main(String[] args) throws Exception {
- /**
- * 1.jdbc对Mysql的insert操作
- */
- // insert("cherry","shanghai");
- /**
- * 2.jdbc对mysql的update操作
- */
- // update("update",12);
- /**
- * 3.jdbc对mysql的delete操作
- */
- // delete(12);
- /**
- * 4.jdbc对mysql的retrieve 操作
- */
- retrieve(15);
- }
- /**
- * jdbc对mysql的insert操作
- *
- * @param username 用户名
- * @param address 地址
- */
- public static void insert(String username,String address) throws Exception {
- Class.forName("com.mysql.jdbc.Driver");
- Connection con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/mydb","root","root");
- //注意下面几行★
- String sql = "insert into t_user(username,address) values(?,?)"; //★
- PreparedStatement sta = con.prepareStatement(sql);
- sta.setString(1, username);
- sta.setString(2, address);
- int rows = sta.executeUpdate();
- if(rows > 0) {
- System.out.println("operate successfully!");
- }
- sta.close();
- con.close();
- }
- /**
- * jdbc对mysql的update操作
- *
- * @param address 地址
- * @param id 主键值
- * @throws Exception
- */
- public static void update(String address,int id) throws Exception {
- Class.forName("com.mysql.jdbc.Driver");
- Connection con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/mydb","root","root");
- //★注意下面几行代码
- String sql = "update t_user set address=? where id=?";
- PreparedStatement sta = con.prepareStatement(sql);
- sta.setString(1, address);
- sta.setInt(2, id);
- int rows = sta.executeUpdate();
- if(rows > 0) {
- System.out.println("operate successfully");
- }
- sta.close();
- con.close();
- }
- /**
- * jdbc对mysql的删除操作
- *
- * @param id
- * @throws Exception
- */
- public static void delete(int id) throws Exception {
- Class.forName("com.mysql.jdbc.Driver");
- Connection con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/mydb","root","root");
- //★注意点
- String sql = "delete from t_user where id=?";
- PreparedStatement sta = con.prepareStatement(sql);
- sta.setInt(1, id);
- int rows = sta.executeUpdate();
- if(rows > 0) {
- System.out.println("operate successfully!!");
- }
- sta.close();
- con.close();
- }
- /**
- * jdbc对mysql的retrieve操作
- *
- * @param id
- * @throws Exception
- */
- public static void retrieve(int id) throws Exception {
- Class.forName("com.mysql.jdbc.Driver");
- Connection con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/mydb","root","root");
- //注意★
- String sql = "select id,username,address from t_user where id=?";
- PreparedStatement sta = con.prepareStatement(sql);
- sta.setInt(1, id);
- ResultSet rs = sta.executeQuery();
- //注意:当现实一条记录时:while可以换成if。★
- if(rs.next()) {
- int did = rs.getInt("id");
- String username = rs.getString("username");
- String address = rs.getString("address");
- System.out.println(did + "\t" + username + "\t" + address);
- }
- rs.close();
- sta.close();
- con.close();
- }
- }
作者:communicate_ 发表于2013-1-10 0:36:13 原文链接
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