Proxool 与 Spring 真的水土不服么？

最近研究Spring的JDBC DataSource配置问题，看到proxool这个东西，根据网上大部分网友的评论，对proxool情有独钟。我于是去下载了一个最新版本：0.9.0RC2，你可以到http://proxool.sf.net/去下载。
我根据官方文档进行了Datasource的配置，但是发现了问题。像大多数网友反应的一样，出现了“参数无效的问题”。我根据源码进行了分析，终于发现了问题所在。

Proxool 指南里配置的例子如下：

5. Configuration example for Tomcat
Configuration method: ObjectFactory
Configure a resource with ProxoolDataSource as the factory in server.xml (or the other places a context element can exist):
                                                                                                <context>
                                                                              

                                                                                                    <Resource
                                                                              

                                                                                                        name="jdbc/mydatasource"
                                                                              

                                                                                                        auth="Container"
                                                                              

                                                                                                        type="javax.sql.DataSource"
                                                                              

                                                                                                        factory="org.logicalcobwebs.proxool.ProxoolDataSource"
                                                                              

                                                                                                        proxool.alias="hrs"
                                                                              

                                                                                                        user="joe"
                                                                              

                                                                                                        password="******"
                                                                              

                                                                                                        delegateProperties="foo=bar"
                                                                              

                                                                                                        proxool.driver-url="jdbc:oracle:thin:@127.0.0.1:1521:DB"
                                                                              

                                                                                                        proxool.driver-class="oracle.jdbc.driver.OracleDriver"/>
                                                                              

</context>




看完后照着例子做，写出简单的配置文件：

<? xml version = "1.0" encoding = "GBK" ?>
<! DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd" >
<!--
    描述: ProxoolSample 默认连接的数据源
    作者:悠游
    时间:2006-08-07
    备注:
         该类的诸多属性请参考Proxool文档.
  
-->

< beans >
    <!-- Proxool 默认连接的数据源 -->
    < bean id = "ProxoolSample"
        class = "org.logicalcobwebs.proxool.ProxoolDataSource" >
        < property name = "driver" >
            < value > ${oracle.121.driverClassName} </ value >
        </ property >
        < property name = "driverUrl" >
            < value > ${oracle.121.url} </ value >
        </ property >
        < property name = "user" >
            < value > ${oracle.121.userName} </ value >
        </ property >
        < property name = "password" >
            < value > ${oracle.121.passWord} </ value >
        </ property >
    </ bean >
  
    <!-- 配置属性文件 -->
    < import resource = "../resource/Properties.xml" />
</ beans >
 


测试，结果和预期一样，参数无效报错了。断点跟踪到最后发现这么一个问题：配置的用户名和密码丢失！

大家都知道以前自己在写连接池的时候最后一步是这个DriverManager.getConnection(url, info)方法。 url就是连接的url，info是属性类。里面最基本要存放两个属性，不用说就知道是user和password。但是断点跟踪到proxool最后一步的时候发现info是空的，所以就出现了上述参数无效的问题。

       回头看问题到底出现在哪里？info不就是一开始的时候注入到工厂里面的delegateProperties属性么？看他的源码如下：
    /**
     * Set any property that should be handed to the delegate driver.
     * E.g. <code>foo=1,bar=true</code>
     * @param properties a comma delimited list of name=value pairs
     * @see ConnectionPoolDefinitionIF#getDelegateProperties()
     */
    public void setDelegateProperties(String properties) {
        StringTokenizer stOuter = new StringTokenizer(properties, "," );
        while (stOuter.hasMoreTokens()) {
            StringTokenizer stInner = new StringTokenizer(stOuter.nextToken(), "=" );
            if (stInner.countTokens() != 2) {
                throw new IllegalArgumentException( "Unexpected delegateProperties value: '" + properties + "'. Expected 'name=value'" );
            }
            delegateProperties.put(stInner.nextToken().trim(), stInner.nextToken().trim());
        }
    }

       不用细看，大概就知道他希望如果有的话把foo=1,bar=true两个附加属性放进去了。那个用户名和密码怎么没放进去呢？自己放算了，于是我这样增加了点东西：

    < property name = "delegateProperties" >
      < value > user=${oracle.121.userName},password=${oracle.121.passWord} </ value >
    </ property >


       测试，结果通过，不过有点投机取巧。因为foo=1,bar=true和user=××,password=××都正好是两个属性。

    知道怎么回事了就行了，看来这是个BUG。经过解析，发现了最终原因：

类： ProxoolDataSource
方法：registerPool
问题:
  
            cpd.setAlias(getAlias());
             cpd.setDriver(getDriver());
            cpd.setFatalSqlExceptionsAsString(getFatalSqlExceptionsAsString());
            cpd.setFatalSqlExceptionWrapper(getFatalSqlExceptionWrapperClass());
            cpd.setHouseKeepingSleepTime(getHouseKeepingSleepTime());
            cpd.setHouseKeepingTestSql(getHouseKeepingTestSql());
            cpd.setMaximumActiveTime(getMaximumActiveTime());
            cpd.setMaximumConnectionCount(getMaximumConnectionCount());
            cpd.setMaximumConnectionLifetime(getMaximumConnectionLifetime());
            cpd.setMinimumConnectionCount(getMinimumConnectionCount());
            cpd.setPrototypeCount(getPrototypeCount());
            cpd.setPassword(getPassword());
            cpd.setRecentlyStartedThreshold(getRecentlyStartedThreshold());
            cpd.setSimultaneousBuildThrottle(getSimultaneousBuildThrottle());
            cpd.setUser(getUser());
            cpd.setStatistics(getStatistics());
            cpd.setStatisticsLogLevel( getStatisticsLogLevel ());
             cpd.setTrace(isTrace());
            cpd.setUrl(getDriverUrl());
            cpd.setVerbose(isVerbose());
            cpd.setJmx(isJmx());
            cpd.setJmxAgentId(getJmxAgentId());
            cpd.setTestAfterUse(isTestAfterUse());
            cpd.setTestBeforeUse(isTestBeforeUse());
            cpd.setDelegateProperties(delegateProperties);

  
cpd 对象里面有个properties属性。在cpd设置完成用户名和密码后，最后一步设置delegateProperties属性的时候把原来的属性给覆盖掉了，这个就是最终原因。改改：

            cpd.setDelegateProperties(delegateProperties);
            cpd.setUser(getUser());
             cpd.setPassword(getPassword());

  
重新bunid、测试、ok！