spring-获取连接的工具类

 1 package learnFromBilibili.util;
 2 
 3 import javax.sql.DataSource;
 4 import java.sql.Connection;
 5 import java.sql.SQLException;
 6 
 7 /**
 8  * 连接的工具类，用于从数据源中获取一个连接，并且实现和线程的绑定
 9  * @author tony fan
10  */
11 public class ConnectionUtils {
12 
13     private ThreadLocal<Connection> threadLocal = new ThreadLocal<>();
14 
15     private DataSource dataSource;
16 
17     public void setDataSource(DataSource dataSource) {
18         this.dataSource = dataSource;
19     }
20 
21     /**
22      * 获取当前线程上的连接
23      */
24     public Connection getThreadConnection(){
25         try {
26             // 1、先从ThreadLocal上获取
27             Connection conn = threadLocal.get();
28             // 2、判断当前线程上是否有连接
29             if(conn == null){
30                 // 3、从数据源中获取一个连接，并且存入ThreadLocal中
31                 conn = dataSource.getConnection();
32                 threadLocal.set(conn);
33             }
34             // 4、返回当前线程上的连接
35             return conn;
36         } catch (SQLException e) {
37             throw new RuntimeException();
38         }
39     }
40 
41     /**
42      * 把连接和线程解绑
43      */
44     public void removeConnection(){
45         threadLocal.remove();
46     }
47     
48 }