我在計算MySQL錯誤日誌時遇到了很多問題

Question

我使用JSF，MySQL和NetBeans（web-app template-design）製作了一個web應用程序。

這裏的誤差跟蹤我得到：http://adelazzam.com/errorTrace.htm

javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException 
Internal Exception: java.sql.SQLException: Error in allocating a connection. Cause: null 
Error Code: 0 
    at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:397) 
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.getServerSession(EntityManagerFactoryImpl.java:151) 
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManagerImpl(EntityManagerFactoryImpl.java:207) 
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:202) 
    at com.sun.enterprise.container.common.impl.EntityManagerWrapper._getDelegate(EntityManagerWrapper.java:207) 
    at com.sun.enterprise.container.common.impl.EntityManagerWrapper.getCriteriaBuilder(EntityManagerWrapper.java:883) 
    at jpa.session.AbstractFacade.count(AbstractFacade.java:56) 
    at jsf.ToolController.getPagingInfo(ToolController.java:45) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 
    at java.lang.reflect.Method.invoke(Method.java:597) 
    at javax.el.BeanELResolver.getValue(BeanELResolver.java:302) 
    at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:175) 
    at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:72) 
    at com.sun.el.parser.AstValue.getValue(AstValue.java:116) 
    at com.sun.el.parser.AstValue.getValue(AstValue.java:163) 
    at com.sun.el.parser.AstEqual.getValue(AstEqual.java:54) 
    at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219) 
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:190) 
    at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:416) 
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1607) 
    at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) 
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:848) 
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1613) 
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1616) 
    at com.sun.faces.application.view.JspViewHandlingStrategy.doRenderView(JspViewHandlingStrategy.java:420) 
    at com.sun.faces.application.view.JspViewHandlingStrategy.renderView(JspViewHandlingStrategy.java:209) 
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:126) 
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:127) 
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) 
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139) 
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313) 
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188) 
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641) 
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97) 
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185) 
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:325) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:226) 
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165) 
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791) 
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693) 
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954) 
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170) 
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135) 
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102) 
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88) 
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76) 
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53) 
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57) 
    at com.sun.grizzly.ContextTask.run(ContextTask.java:69) 
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330) 
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309) 
    at java.lang.Thread.run(Thread.java:619) 
Caused by: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException 
Internal Exception: java.sql.SQLException: Error in allocating a connection. Cause: null 
Error Code: 0 
    at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:309) 
    at org.eclipse.persistence.sessions.JNDIConnector.connect(JNDIConnector.java:138) 
    at org.eclipse.persistence.sessions.JNDIConnector.connect(JNDIConnector.java:94) 
    at org.eclipse.persistence.sessions.DatasourceLogin.connectToDatasource(DatasourceLogin.java:162) 
    at org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.loginAndDetectDatasource(DatabaseSessionImpl.java:584) 
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryProvider.login(EntityManagerFactoryProvider.java:228) 
    at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:369) 
    ... 56 more 
Caused by: java.sql.SQLException: Error in allocating a connection. Cause: null 
    at com.sun.gjc.spi.base.DataSource.getConnection(DataSource.java:112) 
    at org.eclipse.persistence.sessions.JNDIConnector.connect(JNDIConnector.java:126) 
    ... 61 more 

的原因是什麼，我該如何解決？

Answer 1

在大型蹤跡的情況下，總是朝向對lastmost一個真正的根源：

造成的：java.sql.SQLException中：錯誤分配的連接。原因：null

因此，無法從數據源獲取連接。顯然，數據源本身是null。你需要在Glassfish中創建一個MySQL數據源。有幾種方法：

• 通過GlassFish管理控制檯：http://www.albeesonline.com/blog/2008/08/06/creating-and-configuring-a-mysql-datasource-in-glassfish-application-server/

• 通過命令行：http://weblogs.java.net/blog/felipegaucho/archive/2010/03/04/glassfish-v3-resources-administration-cli-tool-asadmin

• 通過XML配置文件：http://pooriamellati.wordpress.com/2010/05/21/configure-mysql-pool-and-resource-in-glassfish-v3/