proxool连接池的实现

作为开源的连接池Proxool有以下优点
透明性   可以明的添加接连池而不影响你原来的项目的JDBC代码；
开放性 你可以方便的与其它的开源产品进行整合。如hibernate  中自带的这个Proxool
标准性 它是在J2SE下开出来的。你可以放心的开发
易用性  非常容易 的进行配置。
proxool是一个非常强大的连接池工具包，我觉得相比dbcp、c3p0这两个连接池包都要好用，我用loadrunner测试过，这三个连接池的从性能上排名如下：proxool>c3p0>dbcp，特别是dbcp在大并发的情况下总是出现各种异常。

下面是实现proxool的几种方式：

JDBC连接方法：
首先建一个proxool的配置文件proxool.xml

proxool.xml 代码

Xml代码

1. xml version="1.0" encoding="UTF-8"?>       
2.      
3.        
4.      
5. <something-else-entirely>     
6.     <proxool>     
7.              
8.         <alias>DBPoolalias>     
9.              
10.         <driver-url>jdbc:oracle:thin:@192.168.0.40:1521:drcomdriver-url>     
11.              
12.         <driver-class>oracle.jdbc.driver.OracleDriverdriver-class>     
13.         <driver-properties>     
14.             <property name="user" value="drcom"/>     
15.             <property name="password" value="drcom"/>     
16.         driver-properties>     
17.              
18.         <house-keeping-sleep-time>90000house-keeping-sleep-time>     
19.                
20.         <maximum-new-connections>150maximum-new-connections>     
21.                
22.         <prototype-count>3prototype-count>     
23.                
24.         <maximum-connection-count>100maximum-connection-count>     
25.              
26.         <minimum-connection-count>3minimum-connection-count>     
27.     proxool>     
28. something-else-entirely>     

xml version="1.0" encoding="UTF-8"?>     
   
     
   
   
    <proxool>   
           
        DBPool   
           
        jdbc:oracle:thin:@192.168.0.40:1521:drcom   
           
        oracle.jdbc.driver.OracleDriver   
           
               
               
           
           
        90000   
             
        150   
             
        3   
             
        100   
           
        3   
    proxool>   
   

再在web.xml中进行配置，其中的ServletConfigurator是装载WEB-INF目录下的proxool.xml,并设置为Tomcat启动时就加载。Admin这个Servlet是proxool提供的察看连接池的信息的工具，


web.xml 代码

Xml代码

1. xml version="1.0" encoding="UTF-8"?>     
2. <web-app version="2.4" xmlns=""     
3.     xmlns:xsi="http:///2001/XMLSchema-instance"     
4.     xsi:schemaLocation="       
5.     /web-app_2_4.xsd">     
6.     <servlet>     
7.         <servlet-name>ServletConfiguratorservlet-name>     
8.         <servlet-class>     
9.             org.logicalcobwebs.proxool.configuration.ServletConfigurator       
10.         servlet-class>     
11.         <init-param>     
12.             <param-name>xmlFileparam-name>     
13.             <param-value>WEB-INF/proxool.xmlparam-value>     
14.         init-param>     
15.         <load-on-startup>1load-on-startup>     
16.     servlet>     
17.     <servlet>     
18.         <servlet-name>Adminservlet-name>     
19.         <servlet-class>     
20.             org.logicalcobwebs.proxool.admin.servlet.AdminServlet       
21.         servlet-class>     
22.     servlet>     
23.     <servlet-mapping>     
24.         <servlet-name>Adminservlet-name>     
25.         <url-pattern>/adminurl-pattern>     
26.     servlet-mapping>     
27.     <servlet>     
28.         <servlet-name>TestServletservlet-name>     
29.         <servlet-class>     
30.             selfservice.TestServlet       
31.         servlet-class>     
32.     servlet>     
33.     <servlet-mapping>     
34.         <servlet-name>TestServletservlet-name>     
35.         <url-pattern>/TestServleturl-pattern>     
36.     servlet-mapping>     
37. web-app>     

xml version="1.0" encoding="UTF-8"?>   
   
       
        ServletConfigurator   
           
            org.logicalcobwebs.proxool.configuration.ServletConfigurator     
           
           
            xml   
            WEB-INF/proxool.xml   
           
        1   
       
       
        Admin   
           
            org.logicalcobwebs.proxool.admin.servlet.AdminServlet     
           
       
       
        Adminservlet-name>   
        /adminurl-pattern>   
       
       
        TestServlet   
           
            selfservice.TestServlet     
           
       
       
        TestServlet   
        /TestServlet   
       
   

以上配置完成后，第三步就可以创建一个连接池的类了

Java代码

1. package selfservice;           
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 org.logicalcobwebs.proxool.ProxoolException;           
10. import org.logicalcobwebs.proxool.ProxoolFacade;           
11. import org.logicalcobwebs.proxool.admin.SnapshotIF;           
12.          
13.          
14. public class PoolManager {           
15.                
16.     private static int activeCount = 0;           
17.                
18.                
19.     public PoolManager(){           
20.                    
21.     }             
22.     /**        
23.      * 获取连接        
24.      * getConnection        
25.      * @param name        
26.      * @return        
27.      */         
28.     public Connection getConnection() {           
29.         try{           
30.             Class.forName("org.logicalcobwebs.proxool.ProxoolDriver");//proxool驱动类           
31.             Connection conn = DriverManager.getConnection("proxool.DBPool");       
32.            //此处的DBPool是在proxool.xml中配置的连接池别名         
33.             showSnapshotInfo();           
34.                        
35.             return conn;           
36.         }catch(Exception ex){           
37.             ex.printStackTrace();           
38.         }           
39.         return null;           
40.     }           
41.     /**        
42.      * 此方法可以得到连接池的信息        
43.      * showSnapshotInfo        
44.      */         
45.     private void showSnapshotInfo(){           
46.         try{           
47.             SnapshotIF snapshot = ProxoolFacade.getSnapshot("DBPool", true);           
48.             int curActiveCount=snapshot.getActiveConnectionCount();//获得活动连接数           
49.             int availableCount=snapshot.getAvailableConnectionCount();//获得可得到的连接数           
50.             int maxCount=snapshot.getMaximumConnectionCount() ;//获得总连接数           
51.             if(curActiveCount!=activeCount)//当活动连接数变化时输出的信息           
52.             {           
53.              System.out.println("活动连接数:"+curActiveCount+"(active)  可得到的连接数:"+availableCount+"(available)  总连接数:"+maxCount+"(max)");                       
54.              activeCount=curActiveCount;           
55.             }           
56.         }catch(ProxoolException e){           
57.             e.printStackTrace();           
58.         }           
59.     }           
60.     /**        
61.      * 获取连接        
62.      * getConnection        
63.      * @param name        
64.      * @return        
65.      */         
66.     public Connection getConnection(String name){           
67.         return getConnection();           
68.     }           
69.     /**        
70.      * 释放连接        
71.      * freeConnection        
72.      * @param conn        
73.      */         
74.     public void freeConnection(Connection conn){           
75.         if(conn!=null){           
76.             try {           
77.                 conn.close();           
78.             } catch (SQLException e) {                         
79.                 e.printStackTrace();           
80.             }           
81.         }           
82.     }           
83.     /**        
84.      * 释放连接        
85.      * freeConnection        
86.      * @param name        
87.      * @param con        
88.      */         
89.     public void freeConnection (String name,Connection con){           
90.         freeConnection(con);           
91.     }           
92.                
93.     public void getQuery() {                   
94.         try {           
95.             Connection conn = getConnection();           
96.             if(conn != null){           
97.                 Statement statement = conn.createStatement();           
98.                 ResultSet rs = statement.executeQuery("select * from tblgxinterface");           
99.                 int c = rs.getMetaData().getColumnCount();           
100.                 while(rs.next()){                             
101.                     System.out.println();           
102.                     for(int i=1;i<=c;i++){           
103.                         System.out.print(rs.getObject(i));           
104.                     }           
105.                 }           
106.                 rs.close();           
107.             }           
108.             freeConnection(conn);           
109.         } catch (SQLException e) {                     
110.             e.printStackTrace();           
111.         }           
112.          
113.     }           
114.          
115. }         

package selfservice;         
       
import java.sql.Connection;         
import java.sql.DriverManager;         
import java.sql.ResultSet;         
import java.sql.SQLException;         
import java.sql.Statement;         
       
import org.logicalcobwebs.proxool.ProxoolException;         
import org.logicalcobwebs.proxool.ProxoolFacade;         
import org.logicalcobwebs.proxool.admin.SnapshotIF;         
       
       
public class PoolManager {         
             
    private static int activeCount = 0;         
             
             
    public PoolManager(){         
                 
    }           
    /**       
     * 获取连接       
     * getConnection       
     * @param name       
     * @return       
     */       
    public Connection getConnection() {         
        try{         
            Class.forName("org.logicalcobwebs.proxool.ProxoolDriver");//proxool驱动类         
            Connection conn = DriverManager.getConnection("proxool.DBPool");     
           //此处的DBPool是在proxool.xml中配置的连接池别名       
            showSnapshotInfo();         
                     
            return conn;         
        }catch(Exception ex){         
            ex.printStackTrace();         
        }         
        return null;         
    }         
    /**       
     * 此方法可以得到连接池的信息       
     * showSnapshotInfo       
     */       
    private void showSnapshotInfo(){         
        try{         
            SnapshotIF snapshot = ProxoolFacade.getSnapshot("DBPool", true);         
            int curActiveCount=snapshot.getActiveConnectionCount();//获得活动连接数         
            int availableCount=snapshot.getAvailableConnectionCount();//获得可得到的连接数         
            int maxCount=snapshot.getMaximumConnectionCount() ;//获得总连接数         
            if(curActiveCount!=activeCount)//当活动连接数变化时输出的信息         
            {         
             System.out.println("活动连接数:"+curActiveCount+"(active)  可得到的连接数:"+availableCount+"(available)  总连接数:"+maxCount+"(max)");                     
             activeCount=curActiveCount;         
            }         
        }catch(ProxoolException e){         
            e.printStackTrace();         
        }         
    }         
    /**       
     * 获取连接       
     * getConnection       
     * @param name       
     * @return       
     */       
    public Connection getConnection(String name){         
        return getConnection();         
    }         
    /**       
     * 释放连接       
     * freeConnection       
     * @param conn       
     */       
    public void freeConnection(Connection conn){         
        if(conn!=null){         
            try {         
                conn.close();         
            } catch (SQLException e) {                       
                e.printStackTrace();         
            }         
        }         
    }         
    /**       
     * 释放连接       
     * freeConnection       
     * @param name       
     * @param con       
     */       
    public void freeConnection (String name,Connection con){         
        freeConnection(con);         
    }         
             
    public void getQuery() {                 
        try {         
            Connection conn = getConnection();         
            if(conn != null){         
                Statement statement = conn.createStatement();         
                ResultSet rs = statement.executeQuery("select * from tblgxinterface");         
                int c = rs.getMetaData().getColumnCount();         
                while(rs.next()){                           
                    System.out.println();         
                    for(int i=1;i<=c;i++){         
                        System.out.print(rs.getObject(i));         
                    }         
                }         
                rs.close();         
            }         
            freeConnection(conn);         
        } catch (SQLException e) {                   
            e.printStackTrace();         
        }         
       
    }         
       
}       

就这样我们完成了一个连接池的功能。proxool的连接池我用loadrunner进行大并发的测试，性能还是很好的。

Hibernate中proxool连接池的方式：

首先步骤跟JDBC的连接池一样，也是新建一个proxool.xml配置文件，再在web.xml中配置，具体参考上面。
第二步在hibernate的配置文件hibernate.cfg.xml中配置proxool连接设置：


hibernate.cfg.xml代码

Xml代码

1. <property name="hibernate.connection.provider_class">org.hibernate.connection.ProxoolConnectionProviderproperty>     
2.             <property name="hibernate.proxool.pool_alias">DBPoolproperty>     
3.             <property name="hibernate.proxool.xml">proxoolconf.xmlproperty>  

org.hibernate.connection.ProxoolConnectionProvider   
            DBPool   
            proxoolconf.xml

Spring中proxool连接池的方式

首先布骤与JDBC的连接池一样，先建一个proxool.xml配置文件，再在web.xml中配置，具体参考上面的。
第二步在spring配置文件applicationContext.xml中配置proxool连接设置

applicationContext.xml代码 

Xml代码

1. <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource" singleton="true">     
2.         <property name="driverClassName" value="org.logicalcobwebs.proxool.ProxoolDriver"/>     
3.         <property name="url" value="proxool.StatDBPool"/>     
4.     bean>     
5.     <bean id="transactionManager"       
6.         class="org.springframework.jdbc.datasource.DataSourceTransactionManager">     
7.         <property name="dataSource">     
8.             <ref local="dataSource" />     
9.         property>     
10.     bean>  

     


这样spring就能得到一个dataSource的数据源。