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Spring源套件spring3 + Hibernate4 + maven 3 + MySQL 5

问题内容：

我的应用程序出现错误，但是我不确定这意味着什么。我在下面发布了一些示例代码。这是我得到的错误：

> SEVERE: Exception sending context initialized event to listener
> instance of class
> org.springframework.web.context.ContextLoaderListener
> org.springframework.beans.factory.BeanCreationException: Error
> creating bean with name 'transactionManager' defined in ServletContext
> resource [/WEB-INF/spring/root-context.xml]: Invocation of init method
> failed; nested exception is
> org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to
> requested type [javax.sql.DataSource]     at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1455)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
>   at
> org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
>   at
> org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585)
>   at
> org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913)
>   at
> org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
>   at
> org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:384)
>   at
> org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:283)
>   at
> org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
>   at
> org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4779)
>   at
> org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5273)
>   at
> org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
>   at
> org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1566)
>   at
> org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1556)
>   at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
>   at java.util.concurrent.FutureTask.run(FutureTask.java:166)     at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
>   at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
>   at java.lang.Thread.run(Thread.java:722) Caused by:
> org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to
> requested type [javax.sql.DataSource]     at
> org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.unwrap(DriverManagerConnectionProviderImpl.java:91)
>   at
> org.springframework.orm.hibernate4.SessionFactoryUtils.getDataSource(SessionFactoryUtils.java:101)
>   at
> org.springframework.orm.hibernate4.HibernateTransactionManager.afterPropertiesSet(HibernateTransactionManager.java:264)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
>   ... 22 more
> 
> ERROR: org.springframework.web.context.ContextLoader - Context
> initialization failed
> org.springframework.beans.factory.BeanCreationException: Error
> creating bean with name 'transactionManager' defined in ServletContext
> resource [/WEB-INF/spring/root-context.xml]: Invocation of init method
> failed; nested exception is
> org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to
> requested type [javax.sql.DataSource]     at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1455)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
>   at
> org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
>   at
> org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
>   at
> org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585)
>   at
> org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913)
>   at
> org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
>   at
> org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:384)
>   at
> org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:283)
>   at
> org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
>   at
> org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4779)
>   at
> org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5273)
>   at
> org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
>   at
> org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1566)
>   at
> org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1556)
>   at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
>   at java.util.concurrent.FutureTask.run(FutureTask.java:166)     at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
>   at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
>   at java.lang.Thread.run(Thread.java:722) Caused by:
> org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to
> requested type [javax.sql.DataSource]     at
> org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.unwrap(DriverManagerConnectionProviderImpl.java:91)
>   at
> org.springframework.orm.hibernate4.SessionFactoryUtils.getDataSource(SessionFactoryUtils.java:101)
>   at
> org.springframework.orm.hibernate4.HibernateTransactionManager.afterPropertiesSet(HibernateTransactionManager.java:264)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
>   at
> org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
>   ... 22 more

这是我的pom文件：

<modelVersion>4.0.0</modelVersion>
<groupId>com.reservosity</groupId>
<artifactId>component</artifactId>
<name>Reservosity</name>
<packaging>war</packaging>
<version>1.0.0-BUILD-SNAPSHOT</version>
<properties>
    <java-version>1.6</java-version>
    <org.springframework-version>3.1.0.RELEASE</org.springframework-version>
    <org.aspectj-version>1.6.9</org.aspectj-version>
    <org.slf4j-version>1.5.10</org.slf4j-version>
</properties>
<dependencies>
    <!-- Spring -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${org.springframework-version}</version>
        <exclusions>
            <!-- Exclude Commons Logging in favor of SLF4j -->
            <exclusion>
                <groupId>commons-logging</groupId>
                <artifactId>commons-logging</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${org.springframework-version}</version>
    </dependency>

    <!-- AspectJ -->
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjrt</artifactId>
        <version>${org.aspectj-version}</version>
    </dependency>

    <!-- Logging -->
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${org.slf4j-version}</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>jcl-over-slf4j</artifactId>
        <version>${org.slf4j-version}</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${org.slf4j-version}</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.15</version>
        <exclusions>
            <exclusion>
                <groupId>javax.mail</groupId>
                <artifactId>mail</artifactId>
            </exclusion>
            <exclusion>
                <groupId>javax.jms</groupId>
                <artifactId>jms</artifactId>
            </exclusion>
            <exclusion>
                <groupId>com.sun.jdmk</groupId>
                <artifactId>jmxtools</artifactId>
            </exclusion>
            <exclusion>
                <groupId>com.sun.jmx</groupId>
                <artifactId>jmxri</artifactId>
            </exclusion>
        </exclusions>
        <scope>runtime</scope>
    </dependency>

    <!-- @Inject -->
    <dependency>
        <groupId>javax.inject</groupId>
        <artifactId>javax.inject</artifactId>
        <version>1</version>
    </dependency>

    <!-- Servlet -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>jsp-api</artifactId>
        <version>2.1</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>4.1.3.Final</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>4.1.1.Final</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>3.1.1.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>cglib</groupId>
        <artifactId>cglib</artifactId>
        <version>2.2.2</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.hibernate.common</groupId>
        <artifactId>hibernate-commons-annotations</artifactId>
        <version>4.0.1.Final</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.20</version>
    </dependency>
    <dependency>
        <groupId>org.javassist</groupId>
        <artifactId>javassist</artifactId>
        <version>3.15.0-GA</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate.javax.persistence</groupId>
        <artifactId>hibernate-jpa-2.0-api</artifactId>
        <version>1.0.1.Final</version>
    </dependency>

    <!-- Test -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.7</version>
        <scope>test</scope>
    </dependency>
</dependencies>
<build>
    <plugins>
        <plugin>
            <artifactId>maven-eclipse-plugin</artifactId>
            <version>2.9</version>
            <configuration>
                <additionalProjectnatures>
                    <projectnature>org.springframework.ide.eclipse.core.springnature</projectnature>
                </additionalProjectnatures>
                <additionalBuildcommands>
                    <buildcommand>org.springframework.ide.eclipse.core.springbuilder</buildcommand>
                </additionalBuildcommands>
                <downloadSources>true</downloadSources>
                <downloadJavadocs>true</downloadJavadocs>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.3.2</version>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
                <compilerArgument>-Xlint:all</compilerArgument>
                <showWarnings>true</showWarnings>
                <showDeprecation>true</showDeprecation>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>exec-maven-plugin</artifactId>
            <version>1.2.1</version>
            <configuration>
                <mainClass>org.test.int1.Main</mainClass>
            </configuration>
        </plugin>
    </plugins>
</build>

服务上下文：

<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->

<!-- Enables the Spring MVC @Controller programming model -->
<annotation-driven />

<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />

<!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <beans:property name="prefix" value="/WEB-INF/views/" />
    <beans:property name="suffix" value=".jsp" />
</beans:bean>

<context:component-scan base-package="com.reservosity.component.controller" />

root-context.xml：

<!-- Root Context: defines shared resources visible to all other web components -->


<bean id="sessionFactory"
    class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="configLocation">
        <value>classpath:hibernate.cfg.xml</value>
    </property>
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />

<bean id="transactionManager"    class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

hibernate.cfg.xml：

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC 
"-//Hibernate/Hibernate Configuration DTD//EN"
 "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
 <hibernate-configuration>
<session-factory>
    <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/******</property>
    <property name="hibernate.connection.username">***</property>
    <property name="hibernate.connection.password">***</property>
    <property name="hibernate.connection.pool_size">10</property>
    <property name="show_sql">true</property>
    <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="hibernate.current_session_context_class">thread</property>
    <mapping class="com.company.component.domain.Company" />
</session-factory>

如果删除bean transactionManager，它可以正常工作，但是当我再次添加它时，会出现看上去很脏的错误。不知道为什么。

    <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

我是春天的hibernate新手，确实可以提供一些帮助！

谢谢

安德鲁


问题答案：

我有完全一样的问题。KyelJmD 在这里建议缺少连接池，看来他是正确的，但是他没有发布解决方案。

因此，我花了一些时间并最终使它工作。要解决此问题，您应该做两件事：

  1. 将这些行添加到hibernate.cfg.xml文件中（可能不需要全部）：
        <property name="hibernate.c3p0.min_size">5</property>
    <property name="hibernate.c3p0.max_size">20</property>
    <property name="hibernate.c3p0.timeout">300</property>
    <property name="hibernate.c3p0.max_statements">50</property>
    <property name="hibernate.c3p0.idle_test_period">3000</property>
  1. 在pom.xml中添加以下依赖项：
        <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-c3p0</artifactId>
        <version>4.1.9.Final</version>
    </dependency>

    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-ehcache</artifactId>
        <version>4.1.9.Final</version>
    </dependency>

没有Maven依赖，Hibernate只会默默地忽略C3P0配置。

通过以上配置，我不再遇到UnknownUnwrapTypeException异常，现在看来它可以正常工作。

我的设置是：Spring 3.2.1，Hibernate 4.1.9，Tomcat 7.0.35。

免责声明：如本问题所述，您不应该使用hibernate.cfg.xml文件。请改用dataSourcebean，因为例如，以后可以将其用于JdbcTemplate。

编辑：

我回答这个问题已经有一段时间了。这似乎是正确的，但我从来不喜欢它，因为这是一种猜测，我们应该避免。

因此，因为我发现了这个问题，并且无法在Hibernate 4.1文档中找到任何内容，所以我试图证明我的评论者和其他评论者“猜测”。

这是一个分步过程，可能对解决其他库中的其他怪异问题也很有用。事实证明，这次确实很容易，发生了什么。

  1. 创建一个Maven项目（或使用现有项目），将Hibernate添加到依赖项中（hibernate-entitymanager，我使用的是此版本4.1.7）。将其导入可以自动附加源代码的IDE（我使用Intellij）
  2. 在堆栈跟踪中，找到UnknownUnwrapTypeException引发了异常（）的类（DriverManagerConnectionProviderImpl），然后在其中进行导航（CTRL-N并键入类名），单击“下载源代码”。
  3. 查找DriverManagerConnectionProviderImpl（ALT + F7）的用法
  4. 瞧！事实证明，只有一种用法DriverManagerConnectionProviderImpl-它是其中的一种initiateService(...)方法ConnectionProviderInitiator- ConnectionProvider在回退到之前，或多或少-尝试了几个实现，DriverManagerConnectionProviderImpl在我们的情况下这是行不通的，并且抛出UnknownUnwrapTypeException。

从Hibernate的ConnectionProviderInitiator.java中：

            ConnectionProvider connectionProvider = null;
        String providerClassName = getConfiguredConnectionProviderName( configurationValues );
        if ( providerClassName != null ) {
            connectionProvider = instantiateExplicitConnectionProvider( providerClassName, classLoaderService );
        }
        else if ( configurationValues.get( Environment.DATASOURCE ) != null ) {
            connectionProvider = new DatasourceConnectionProviderImpl();
        }

        if ( connectionProvider == null ) {
            if ( c3p0ConfigDefined( configurationValues ) && c3p0ProviderPresent( classLoaderService ) ) {
                connectionProvider = instantiateExplicitConnectionProvider( C3P0_PROVIDER_CLASS_NAME,
                        classLoaderService
                );
            }
        }

        if ( connectionProvider == null ) {
            if ( proxoolConfigDefined( configurationValues ) && proxoolProviderPresent( classLoaderService ) ) {
                connectionProvider = instantiateExplicitConnectionProvider( PROXOOL_PROVIDER_CLASS_NAME,
                        classLoaderService
                );
            }
        }

        if ( connectionProvider == null ) {
            if ( configurationValues.get( Environment.URL ) != null ) {
                connectionProvider = new DriverManagerConnectionProviderImpl();
            }
        }

        if ( connectionProvider == null ) {
            LOG.noAppropriateConnectionProvider();
            connectionProvider = new UserSuppliedConnectionProviderImpl();
        }

该代码大致显示：

  1. 如果Environment.DATASOURCE设置了（hibernate.connection.datasource），则DatasourceConnectionProviderImpl使用;
  2. 如果存在c3p0，则实例化C3P0 Provider
  3. 检查了其他提供者（PROXOOL_PROVIDER_CLASS_NAME）
  4. 然后，如果存在Environment.URL（hibernate.connection.url），则使用DriverManagerConnectionProviderImpl。

就是这样。这解释了为什么我们将C3P0添加为Maven Dependency或定义DataSource可以解决问题。

另一个问题是为什么DriverManagerConnectionProviderImpl抛出UnknownUnwrapTypeException-
不管它是否是错误-无论如何，我看不到Hibernate 4.2.0甚至4.3.0.Beta中的代码有任何更改。