JDBC连接数据库并执行语句入门案例
时间：2021-07-01 10:21:17
帮助过：11人阅读
package com.yxfyg.test;
2
3 import java.sql.Connection;
4 import java.sql.DriverManager;
5 import java.sql.ResultSet;
6 import java.sql.SQLException;
7 import java.sql.Statement;
8
9 import com.yxfyg.util.JDBCUtil;
10
11 public class MainTest {
12
13 public static void main(String[] args) {
14
15 Connection conn =
null;
16 Statement st =
null;
17 ResultSet rs =
null;
18 try {
19 //1.注册驱动
20 DriverManager.registerDriver(
new com.mysql.jdbc.Driver());
21 //2.获取连接
22 conn = DriverManager.getConnection("jdbc:mysql://localhost/mydb?user=root&password=root"
);
23 //3.创建statement，跟数据库打交道，一定需要这个对象
24 st =
conn.createStatement();
25 //4.执行查询，得到结果集
26 String sql = "select * from student"
;
27 rs =
st.executeQuery(sql);
28 //5.遍历查询每一条记录
29 while(rs.next()) {
30 int sno = rs.getInt("sno"
);
31 String sname = rs.getString("sname"
);
32 String sex = rs.getString("ssex"
);
33 int sage = rs.getInt("sage"
);
34 String sdept = rs.getString("sdept"
);
35 System.out.println("sno="+ sno +",sname="+ sname +",sex="+ sex +",age="+ sage +",sdept=" +
sdept);
36 }
37 }
catch (SQLException e) {
38 e.printStackTrace();
39 }
finally {
40 //6.释放资源
41 JDBCUtil.release(rs, st, conn);
42 }
43 }
44 }
1 package com.yxfyg.util;
2
3 import java.sql.Connection;
4 import java.sql.ResultSet;
5 import java.sql.SQLException;
6 import java.sql.Statement;
7
8 public class JDBCUtil {
9
10 public static void release(ResultSet rs,Statement st,Connection conn) {
11 closeRs(rs);
12 closeSt(st);
13 closeConn(conn);
14 }
15
16 private static void closeRs(ResultSet rs) {
17 try {
18 if(rs != null) {
19 rs.close();
20 }
21 }catch(SQLException e) {
22 e.printStackTrace();
23 }finally {
24 rs = null;
25 }
26 }
27
28 private static void closeSt(Statement st) {
29 try {
30 if(st != null) {
31 st.close();
32 }
33 }catch(SQLException e) {
34 e.printStackTrace();
35 }finally {
36 st = null;
37 }
38 }
39
40 private static void closeConn(Connection conn) {
41 try {
42 if(conn != null) {
43 conn.close();
44 }
45 }catch(SQLException e) {
46 e.printStackTrace();
47 }finally {
48 conn = null;
49 }
50 }
51
52 }
JDBC连接数据库并执行语句入门案例
标签：except gets rom mysq driver sql pac static int
