配置以通过JNDI数据源连接到数据库

小编典典

配置以通过JNDI数据源连接到数据库

hibernate

大家好，我使用Hibernate + Struts2 + Tomcat6 +
Mysql作为我的J2EE框架。我一直在使用hibernate的内置连接池机制，但事实证明，在8小时后mysql关闭其连接的地方，这是一个问题。无论如何，我在Google上搜索了一下，发现我应该通过JNDI数据源获得连接，但是我无法获得关于此的完整的教程。我应该采取什么步骤呢？请提供足够的详细信息，对此我有点陌生。这是我的hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>

    <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">
            jdbc:mysql://localhost/hposg?characterEncoding=UTF-8
    </property>
    <property name="connection.username">root</property>
    <property name="connection.password"></property>
    <property name="show_sql">true</property>
    <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="current_session_context_class">thread</property>
    <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
    <property name="hbm2ddl.auto">update</property>

    <property name="hibernate.max_fetch_depth">3</property>

    <property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
    <property name="hibernate.c3p0.acquire_increment">2</property>
    <property name="hibernate.c3p0.idle_test_period">300</property>
    <property name="hibernate.c3p0.timeout">1800</property>
    <property name="hibernate.c3p0.max_size">25</property>
    <property name="hibernate.c3p0.min_size" >3</property>
    <property name="hibernate.c3p0.max_statement">0</property>
    <property name="hibernate.c3p0.preferredTestQuery">select 1;</property>
    <property name="hibernate.c3p0.testConnectionOnCheckout">true</property>
    <property name="hibernate.c3p0.validate">true</property>

      <!-- Mapping files -->

      <mapping resource="com/hposg/hibernate/resources/Player.hbm.xml"/>
      <mapping resource="com/hposg/hibernate/resources/Game.hbm.xml"/>
      ...

  </session-factory>
</hibernate-configuration>

我也尝试过此方法，但没有成功：在WebContent / META-INF中创建一个context.xml，其中包含：

<Context path="" docBase="../RSGames" debug="0" reloadable="true">
    <Resource name="jdbc/RSGames" auth="Container" type="javax.sql.DataSource"
         username="root"
         password=""
         driverClassName="com.mysql.jdbc.Driver"
         url="jdbc:mysql://localhost:3306/hposg?autoReconnect=true&amp;useUnicode=true&amp;characterEncoding=utf8"
         maxActive="15"
         maxIdle="7"
         validationQuery="Select 1" />
</Context>

将其放在web.xml中：

<resource-ref>
    <description>Connection Pool</description>
    <res-ref-name>jdbc/RSGames</res-ref-name>
    <res-type>javax.sql.Datasource</res-type>
    <res-auth>Container</res-auth>
</resource-ref>

并修改hibernate配置，如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
  ...
    <property name="connection.datasource">java:comp/env/jdbc/RSGames</property>
  ...
  </session-factory>
</hibernate-configuration>

正如我之前提到的，它不会以这种方式连接到数据库。有任何想法吗？

[编辑]执行应用程序时，出现以下异常：

Mar 16, 2011 12:29:13 AM com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
WARNING: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1f18cbe -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
java.lang.NullPointerException
    at sun.jdbc.odbc.JdbcOdbcDriver.getProtocol(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.knownURL(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.acceptsURL(Unknown Source)
    at java.sql.DriverManager.getDriver(Unknown Source)
    at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:224)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:120)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:143)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:132)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Mar 16, 2011 12:29:13 AM com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
WARNING: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@14f1726 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
java.lang.NullPointerException
    at sun.jdbc.odbc.JdbcOdbcDriver.getProtocol(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.knownURL(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.acceptsURL(Unknown Source)
    at java.sql.DriverManager.getDriver(Unknown Source)
    at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:224)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:120)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:143)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:132)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Mar 16, 2011 12:29:13 AM com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
WARNING: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@cad437 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
java.lang.NullPointerException
    at sun.jdbc.odbc.JdbcOdbcDriver.getProtocol(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.knownURL(Unknown Source)
    at sun.jdbc.odbc.JdbcOdbcDriver.acceptsURL(Unknown Source)
    at java.sql.DriverManager.getDriver(Unknown Source)
    at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:224)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:120)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:143)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:132)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
29994 [http-8081-3] WARN org.hibernate.cfg.SettingsFactory - Could not obtain connection to query metadata
java.sql.SQLException: Connections could not be acquired from the underlying database!
    at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:529)
    at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
    at org.hibernate.connection.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:78)
    at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:114)
    at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2163)
    at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2159)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1383)
    at com.hposg.hibernate.util.HibernateUtil.buildSessionFactory(HibernateUtil.java:12)
    at com.hposg.hibernate.util.HibernateUtil.<clinit>(HibernateUtil.java:7)
    at com.hposg.login.LoginFactory.doLogin(LoginFactory.java:25)
    at com.hposg.controller.struts.LoginAction.execute(LoginAction.java:59)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:441)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:280)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:243)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:252)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:130)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:165)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488)
    at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
    at java.lang.Thread.run(Unknown Source)
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
    at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1319)
    at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:557)
    at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:477)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:525)
    ... 74 more

阅读 276

2020-06-20

共1个答案

小编典典

显然，您做对了。但是，这里列出了您需要的东西以及正在运行的应用程序中的示例：

1）META-INF中的context.xml文件，指定您的数据源：

<Context>
    <Resource 
        name="jdbc/DsWebAppDB" 
        auth="Container" 
        type="javax.sql.DataSource" 
        username="sa" 
        password="" 
        driverClassName="org.h2.Driver" 
        url="jdbc:h2:mem:target/test/db/h2/hibernate" 
        maxActive="8" 
        maxIdle="4"/>
</Context>

2）web.xml告诉容器您正在使用此资源：

<resource-env-ref>
    <resource-env-ref-name>jdbc/DsWebAppDB</resource-env-ref-name>
    <resource-env-ref-type>javax.sql.DataSource</resource-env-ref-type>
</resource-env-ref>

3）使用数据源的hibernate配置。在这种情况下，它是一个persistence.xml，但在hibernate.cfg.xml

<persistence-unit name="dswebapp">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <properties>
        <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect" />
        <property name="hibernate.connection.datasource" value="java:comp/env/jdbc/DsWebAppDB"/>
    </properties>
</persistence-unit>

2020-06-20