This project exists to demonstrate the problem outlined in https://stackoverflow.com/questions/36885891/jpa-eclipselink-understanding-classloader-issues
The test only passes if the classloader for JPA is set to the DataSource's classloader.
To reproduce run mvn clean verify. The test is copied into two variants so that one passes and one fails due to the classloader setting.
The application only starts on Tomcat if
- DBCP is used (for both classloader variants), or
- the Tomcat connection pool is used and JPA uses the original classloader and the app is deployed on a real Tomcat server (so not using
mvn tomcat7:run)
To reproduce, you need to be able to connect to some (local?) PostgreSQL instance. For this, configure the credentials in the JSON string below (https://jsonformatter.curiousconcept.com/ might help with the formatting) and export the two values as environment variables. I appreciate any input on how this can be simplified, for example by using H2 with the connection pool variants.
VCAP_APPLICATION={}
VCAP_SERVICES={"postgresql-9.3":[{"name":"postgresql-lite","label":"postgresql-9.3","credentials":{"dbname":"test","hostname":"127.0.0.1","password":"test123!","port":"5432","uri":"postgres://testuser:test123!@localhost:5432/test","username":"testuser"},"tags":["relational","postgresql"],"plan":"free"}]}
Then, run mvn clean tomcat7:run.
The configuration as in this commit re-orders the connection pool implementations tried by spring-cloud, so that DBCP is used.
PM org.springframework.cloud.service.relational.BasicDbcpPooledDataSourceCreator create
INFO: Found DBCP2 on the classpath. Using it for DataSource connection pooling.
If you change this configuration by registering CloudDatabaseConfig instead of CloudDatabaseConfigDbcp in ContextListener#getClassesToRegister, then Tomcat is unable to start:
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:753)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538)
at com.test.ContextListener.<init>(ContextListener.java:23)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at java.lang.Class.newInstance(Class.java:442)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:143)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4854)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: javax.persistence.PersistenceException: Exception [EclipseLink-28019] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.EntityManagerSetupException
Exception Description: Deployment of PersistenceUnit [b] failed. Close all factories for this PersistenceUnit.
Internal Exception: Exception [EclipseLink-7156] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.ValidationException
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.createDeployFailedPersistenceException(EntityManagerSetupImpl.java:869)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:809)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getAbstractSession(EntityManagerFactoryDelegate.java:205)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getMetamodel(EntityManagerFactoryDelegate.java:646)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.getMetamodel(EntityManagerFactoryImpl.java:549)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.invokeProxyMethod(AbstractEntityManagerFactoryBean.java:388)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean$ManagedEntityManagerFactoryInvocationHandler.invoke(AbstractEntityManagerFactoryBean.java:541)
at com.sun.proxy.$Proxy36.getMetamodel(Unknown Source)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.getMetamodels(JpaMetamodelMappingContextFactoryBean.java:90)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:56)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:26)
at org.springframework.beans.factory.config.AbstractFactoryBean.afterPropertiesSet(AbstractFactoryBean.java:134)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
... 25 more
Caused by: Exception [EclipseLink-28019] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.EntityManagerSetupException
Exception Description: Deployment of PersistenceUnit [b] failed. Close all factories for this PersistenceUnit.
Internal Exception: Exception [EclipseLink-7156] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.ValidationException
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.eclipse.persistence.exceptions.EntityManagerSetupException.deployFailed(EntityManagerSetupException.java:239)
... 43 more
Caused by: Exception [EclipseLink-7156] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.ValidationException
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.eclipse.persistence.exceptions.ValidationException.unableToLoadClass(ValidationException.java:2007)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityListenerMetadata.getClass(EntityListenerMetadata.java:227)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityClassListenerMetadata.process(EntityClassListenerMetadata.java:81)
at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.processListeners(EntityAccessor.java:1226)
at org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.addEntityListeners(MetadataProcessor.java:140)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:637)
... 41 more
Caused by: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.eclipse.persistence.internal.security.PrivilegedAccessHelper.getClassForName(PrivilegedAccessHelper.java:139)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityListenerMetadata.getClass(EntityListenerMetadata.java:224)
... 45 more
I get another error when I start using mvn tomcat7:run, use Tomcat's connection pool (CloudDatabaseConfig) and do not re-configure the classloder (JpaConfig):
EDIT: Solved, see http://stackoverflow.com/a/37196365/947526
SEVERE: Error configuring application listener of class com.test.ContextListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: org.postgresql.Driver
Error Code: 0
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:753)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538)
at com.test.ContextListener.<init>(ContextListener.java:23)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at java.lang.Class.newInstance(Class.java:442)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:143)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4854)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: org.postgresql.Driver
Error Code: 0
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:815)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getAbstractSession(EntityManagerFactoryDelegate.java:205)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getMetamodel(EntityManagerFactoryDelegate.java:646)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.getMetamodel(EntityManagerFactoryImpl.java:549)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.invokeProxyMethod(AbstractEntityManagerFactoryBean.java:388)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean$ManagedEntityManagerFactoryInvocationHandler.invoke(AbstractEntityManagerFactoryBean.java:541)
at com.sun.proxy.$Proxy36.getMetamodel(Unknown Source)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.getMetamodels(JpaMetamodelMappingContextFactoryBean.java:90)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:56)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:26)
at org.springframework.beans.factory.config.AbstractFactoryBean.afterPropertiesSet(AbstractFactoryBean.java:134)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
... 25 more
Caused by: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: org.postgresql.Driver
Error Code: 0
at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:316)
at org.eclipse.persistence.sessions.JNDIConnector.connect(JNDIConnector.java:147)
at org.eclipse.persistence.sessions.DatasourceLogin.connectToDatasource(DatasourceLogin.java:162)
at org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.setOrDetectDatasource(DatabaseSessionImpl.java:207)
at org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.loginAndDetectDatasource(DatabaseSessionImpl.java:760)
at org.eclipse.persistence.internal.jpa.EntityManagerFactoryProvider.login(EntityManagerFactoryProvider.java:265)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:731)
... 41 more
Caused by: java.sql.SQLException: org.postgresql.Driver
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254)
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:701)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:635)
at org.apache.tomcat.jdbc.pool.ConnectionPool.getConnection(ConnectionPool.java:188)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:127)
at org.eclipse.persistence.sessions.JNDIConnector.connect(JNDIConnector.java:135)
... 46 more
Caused by: java.lang.ClassNotFoundException: org.postgresql.Driver
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:246)
... 52 more
With a real Tomcat the application starts when I do not re-configure the classpath. With the DataSource's classpath I get:
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.eclipse.persistence.exceptions.EntityManagerSetupException.deployFailed(EntityManagerSetupException.java:239)
... 79 more
Caused by: Exception [EclipseLink-7156] (Eclipse Persistence Services - 2.6.2.v20151217-774c696): org.eclipse.persistence.exceptions.ValidationException
Exception Description: Unable to find the class named [com.test.BaseEntity]. Ensure the class name/path is correct and available to the classloader.
Internal Exception: java.lang.ClassNotFoundException: com.test.BaseEntity
at org.eclipse.persistence.exceptions.ValidationException.unableToLoadClass(ValidationException.java:2007)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityListenerMetadata.getClass(EntityListenerMetadata.java:227)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityClassListenerMetadata.process(EntityClassListenerMetadata.java:81)
at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.processListeners(EntityAccessor.java:1226)
at org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.addEntityListeners(MetadataProcessor.java:140)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:637)
... 77 more
Caused by: java.lang.ClassNotFoundException: com.test.BaseEntity
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.eclipse.persistence.internal.security.PrivilegedAccessHelper.getClassForName(PrivilegedAccessHelper.java:139)
at org.eclipse.persistence.internal.jpa.metadata.listeners.EntityListenerMetadata.getClass(EntityListenerMetadata.java:224)
... 81 more
You can also experiment with the classloader to use for JPA by registering JpaConfig instead of JpaConfigWithDatasourceClassloader.