1 import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.SQLException;
 4 import java.sql.Statement;
 5 
 6 /**
 7  * 创建一张学生表
 8  */
 9 public class Demo {
10     public static void main(String[] args) {
11         //1. 创建连接
12         Connection conn = null;
13         Statement statement = null;
14         try {
15             conn = DriverManager.getConnection("jdbc:mysql:///school", "root", "root");
16             //2. 通过连接对象得到语句对象
17             statement = conn.createStatement();
18             //3. 通过语句对象发送 SQL 语句给服务器
19             //4. 执行 SQL
20             statement.executeUpdate("create table student (id int PRIMARY key auto_increment, " +
21                     "name varchar(20) not null, gender boolean, birthday date)");
22             //5. 返回影响行数(DDL 没有返回值)
23             System.out.println("创建表成功");
24         } catch (SQLException e) {
25             e.printStackTrace();
26         }
27             //6. 释放资源
28         finally {
29             //关闭之前要先判断
30             if (statement != null) {
31                 try {
32                     statement.close();
33                 } catch (SQLException e) {
34                     e.printStackTrace();
35                 }
36             }
37             if (conn != null) {
38                 try {
39                     conn.close();
40                 } catch (SQLException e) {
41                     e.printStackTrace();
42                 }
43             }
44         }
45     }
46 }

 1 import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.SQLException;
 4 import java.sql.Statement;
 5 
 6 /**
 7  * 向学生表中添加 4 条记录，主键是自动增长
 8  */
 9 public class Demo {
10     public static void main(String[] args) throws SQLException {
11         // 1) 创建连接对象
12         Connection connection = DriverManager.getConnection("jdbc:mysql:///school", "root",
13                 "root");
14         // 2) 创建 Statement 语句对象
15         Statement statement = connection.createStatement();
16         // 3) 执行 SQL 语句： executeUpdate(sql)
17         int count = 0;
18         // 4) 返回影响的行数
19         count += statement.executeUpdate("insert into student values(null, '孙悟空', 1, '1993-03-24')");
20         count += statement.executeUpdate("insert into student values(null, '白骨精', 0, '1995-03-24')");
21         count += statement.executeUpdate("insert into student values(null, '猪八戒', 1, '1903-03-24')");
22         count += statement.executeUpdate("insert into student values(null, '嫦娥', 0, '1993-03-11')");
23         System.out.println("插入了" + count + "条记录");
24         // 5) 释放资源
25         statement.close();
26         connection.close();
27     }
28 }

 1 import java.sql.*;
 2 
 3 /**
 4  * 查询所有的学生信息
 5  */
 6 public class Demo5 {
 7     public static void main(String[] args) throws SQLException {
 8         //1) 得到连接对象
 9         Connection connection =
10                 DriverManager.getConnection("jdbc:mysql://localhost:3306/school","root","root");
11         //2) 得到语句对象
12         Statement statement = connection.createStatement();
13         //3) 执行 SQL 语句得到结果集 ResultSet 对象
14         ResultSet rs = statement.executeQuery("select * from student");
15         //4) 循环遍历取出每一条记录
16         while(rs.next()) {
17             int id = rs.getInt("id");
18             String name = rs.getString("name");
19             boolean gender = rs.getBoolean("gender");
20             Date birthday = rs.getDate("birthday");
21             //5) 输出的控制台上
22             System.out.println("编号： " + id + ", 姓名： " + name + ", 性别： " + gender + ", 生日： " +
23                     birthday);
24         }
25         //6) 释放资源
26         rs.close();
27         statement.close();
28         connection.close();
29     }
30 }

 1 import cn.ks.utils.JDBCUtils;
 2 import java.sql.Connection;
 3 import java.sql.PreparedStatement;
 4 import java.sql.SQLException;
 5 public class Demo6 {
 6     //没有异常，提交事务，出现异常回滚事务
 7     public static void main(String[] args) {
 8         //1) 注册驱动
 9         Connection connection = null;
10         PreparedStatement ps = null;
11         try {
12             //2) 获取连接
13             connection = JDBCUtils.getConnection();
14             //3) 开启事务
15             connection.setAutoCommit(false);
16             //4) 获取到 PreparedStatement
17             //从 jack 扣钱
18             ps = connection.prepareStatement("update account set balance = balance - ? where name=?");
19             ps.setInt(1, 500);
20             ps.setString(2,"Jack");
21             ps.executeUpdate();
22             //出现异常
23             System.out.println(100 / 0);
24             //给 rose 加钱
25             ps = connection.prepareStatement("update account set balance = balance + ? where name=?");
26             ps.setInt(1, 500);
27             ps.setString(2,"Rose");
28             ps.executeUpdate();
29             //提交事务
30             connection.commit();
31             System.out.println("转账成功");
32         } catch (Exception e) {
33             e.printStackTrace();
34             try {
35             //事务的回滚
36                 connection.rollback();
37             } catch (SQLException e1) {
38                 e1.printStackTrace();
39             }
40             System.out.println("转账失败");
41         }
42         finally {
43         //7) 关闭资源
44             JDBCUtils.close(ps,connection);
45         }
46     }
47 }