java - C3P0 + Hibernate ClassNotFoundException : com. mchange.v2.log.MLog

Question

我将 Java EE DAL 设置为 jar 库。我使用JPA + Hibernate + C3P0进行连接池管理。 EntityManager 类由以下 bean 生成

package my.dal;

import javax.enterprise.inject.Alternative;
import javax.enterprise.inject.Default;
import javax.enterprise.inject.Produces;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.PersistenceContext;

@Alternative
@Default
public class EntityManagerProvider {

    private EntityManager entityManager;

    @Default
    @Produces
    @PersistenceContext 
    public EntityManager getEntityManager() {
        if(entityManager == null) {
            EntityManagerFactory emf = Persistence.createEntityManagerFactory("DALPersistenceUnit");
            entityManager = emf.createEntityManager();
        }

        return entityManager;
    }

}

然后，DAO 类注入(inject) EntityManager 并使用它

package my.dal.dao;

@Default
public class UserDAO {

    @Inject private EntityManager entityManager;
    public User find(String username)
    {
        ...
    }

    ...
}

这些是在 pom.xml 中设置的 C3P0 依赖项

<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>c3p0</artifactId>
    <version>0.9.2.1</version>
</dependency>

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-c3p0</artifactId>
    <version>4.3.5.Final</version>
</dependency>

<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>mchange-commons-java</artifactId>
    <version>0.2.3.4</version>
</dependency>

我编写了一个测试类(名为DALUserTest)，它注入(inject) DAO 类并使用它在数据库上保存数据。问题是，每当我尝试运行测试时，应用程序都会在注入(inject)步骤停止并抛出以下异常堆栈

javax.enterprise.inject.CreationException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at org.jboss.weld.security.NewInstanceAction.run(NewInstanceAction.java:33)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.jboss.weld.injection.Exceptions.rethrowException(Exceptions.java:40)
    at org.jboss.weld.injection.Exceptions.rethrowException(Exceptions.java:78)
    at org.jboss.weld.injection.MethodInjectionPoint.invokeOnInstanceWithSpecialValue(MethodInjectionPoint.java:101)
    at org.jboss.weld.injection.MethodInjectionPoint.invokeOnInstance(MethodInjectionPoint.java:86)
    at org.jboss.weld.injection.producer.ProducerMethodProducer.produce(ProducerMethodProducer.java:96)
    at org.jboss.weld.injection.producer.AbstractMemberProducer.produce(AbstractMemberProducer.java:151)
    at org.jboss.weld.bean.AbstractProducerBean.create(AbstractProducerBean.java:183)
    at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:69)
    at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:733)
    at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:789)
    at org.jboss.weld.injection.FieldInjectionPoint.inject(FieldInjectionPoint.java:92)
    at org.jboss.weld.util.Beans.injectBoundFields(Beans.java:358)
    at org.jboss.weld.util.Beans.injectFieldsAndInitializers(Beans.java:369)
    at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:72)
    at org.jboss.weld.injection.producer.ResourceInjector.inject(ResourceInjector.java:60)
    at org.jboss.weld.injection.producer.DefaultInjector$1.proceed(DefaultInjector.java:66)
    at org.jboss.weld.injection.InjectionContextImpl.run(InjectionContextImpl.java:48)
    at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:64)
    at org.jboss.weld.injection.producer.BasicInjectionTarget.inject(BasicInjectionTarget.java:90)
    at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:150)
    at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:69)
    at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:733)
    at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:789)
    at org.jboss.weld.injection.FieldInjectionPoint.inject(FieldInjectionPoint.java:92)
    at org.jboss.weld.util.Beans.injectBoundFields(Beans.java:358)
    at org.jboss.weld.util.Beans.injectFieldsAndInitializers(Beans.java:369)
    at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:72)
    at org.jboss.weld.injection.producer.ResourceInjector.inject(ResourceInjector.java:60)
    at org.jboss.weld.injection.producer.DefaultInjector$1.proceed(DefaultInjector.java:66)
    at org.jboss.weld.injection.InjectionContextImpl.run(InjectionContextImpl.java:48)
    at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:64)
    at org.jboss.weld.injection.producer.BasicInjectionTarget.inject(BasicInjectionTarget.java:90)
    at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:150)
    at org.jboss.weld.context.AbstractContext.get(AbstractContext.java:96)
    at org.jboss.weld.bean.proxy.ContextBeanInstance.getInstance(ContextBeanInstance.java:98)
    at org.jboss.weld.bean.proxy.ProxyMethodHandler.invoke(ProxyMethodHandler.java:78)
    at my.dal.test.DALUserTest$Proxy$_$$_WeldClientProxy.testInsert(Unknown Source)
    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 org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.jglue.cdiunit.CdiRunner$2.evaluate(CdiRunner.java:139)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.NoClassDefFoundError: com/mchange/v2/log/MLog
    at com.mchange.v2.c3p0.DataSources.<clinit>(DataSources.java:72)
    at org.hibernate.c3p0.internal.C3P0ConnectionProvider.configure(C3P0ConnectionProvider.java:203)
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:89)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:206)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:178)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.buildJdbcConnectionAccess(JdbcServicesImpl.java:260)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:94)
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:89)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:206)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:178)
    at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1885)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1843)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
    at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:399)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
    at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:75)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:79)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:54)
    at my.dal.EntityManagerProvider.getEntityManager(EntityManagerProvider.java:22)
    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 org.jboss.weld.injection.MethodInjectionPoint.invokeOnInstanceWithSpecialValue(MethodInjectionPoint.java:93)
    ... 58 more
Caused by: java.lang.ClassNotFoundException: com.mchange.v2.log.MLog
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 83 more

我用谷歌搜索了很多，但没有任何帮助我解决这个问题。您认为问题可能出在哪里？

谢谢

Answer 1

下载mchange-commons-java-0.2.16.jar解决错误java.lang.NoClassDefFoundError: com/mchange/v2/log/MLog