[ https://jira.jboss.org/jira/browse/JBSEAM-3925?page=com.atlassian.jira.pl... ] Takayoshi Kimura updated JBSEAM-3925: ------------------------------------- Fix Version/s: (was: 2.0.0.GA) Affects Version/s: 2.0.0.GA Description: The ProxyFactory#createClass() method is not thread safe and causes LinkageError under heavy load. This is same problem as JASSIST-28: https://jira.jboss.org/jira/browse/JASSIST-28 Seam has a little bit modified version of ProxyFactory taken from Javassist 3.3. This race condition issue has been fixed in Javassist 3.4. In Javassist 3.4 this method has a synchronized block and also weak ref based cache mechanism has been added. The ProxyFactory#createClass() is not thread safe and called from the following 3 methods: 1. Component#getProxyFactory(), this method is a synchronized method 2. ClientSideInterceptor#readResolve() 3. JavaBeanInterceptor#readResolve() 1 and (2 or 3) can run at the same time. Possible options: * Re-sync ProxyFacotory source code with 3.4 or later version * Add a synchronized modifier/block to the ProxyFacotory#createClass() method Exception stack trace: Caused by: org.jboss.seam.InstantiationException: Could not instantiate Seam component: test at org.jboss.seam.Component.newInstance(Component.java:1986) at org.jboss.seam.Component.getInstance(Component.java:1876) at org.jboss.seam.Component.getInstance(Component.java:1843) at org.jboss.seam.Component.getInstanceInAllNamespaces(Component.java:2192) at org.jboss.seam.Component.getValueToInject(Component.java:2144) at org.jboss.seam.Component.injectAttributes(Component.java:1601) at org.jboss.seam.Component.inject(Component.java:1419) at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:45) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:42) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.persistence.EntityManagerProxyInterceptor.aroundInvoke(EntityManagerProxyInterceptor.java:26) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.persistence.HibernateSessionProxyInterceptor.aroundInvoke(HibernateSessionProxyInterceptor.java:27) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) at org.jboss.seam.intercept.SessionBeanInterceptor.aroundInvoke(SessionBeanInterceptor.java:50) 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:585) at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:118) at org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke(EJB3InterceptorsInterceptor.java:63) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.ejb3.entity.TransactionScopedEntityManagerInterceptor.invoke(TransactionScopedEntityManagerInterceptor.java:54) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOperationsInterceptor.java:47) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:79) ... 184 more Caused by: java.lang.RuntimeException: by java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at org.jboss.seam.util.ProxyFactory.createClass(ProxyFactory.java:190) at org.jboss.seam.Component.createProxyFactory(Component.java:2270) at org.jboss.seam.Component.getProxyFactory(Component.java:1378) at org.jboss.seam.Component.wrap(Component.java:1369) at org.jboss.seam.Component.instantiateSessionBean(Component.java:1291) at org.jboss.seam.Component.instantiate(Component.java:1276) at org.jboss.seam.Component.newInstance(Component.java:1970) ... 212 more Caused by: javassist.CannotCompileException: by java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:165) at org.jboss.seam.util.ProxyFactory.createClass(ProxyFactory.java:186) ... 218 more Caused by: java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:620) at sun.reflect.GeneratedMethodAccessor50.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at javassist.util.proxy.FactoryHelper.toClass2(FactoryHelper.java:177) at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:159) ... 219 more was: java.lang.LinkageError: duplicate class definition in ProxyFactory The ProxyFactory#createClass() method is not thread safe and causes LinkageError under heavy load. This is same problem as JASSIST-28: https://jira.jboss.org/jira/browse/JASSIST-28 Seam has a little bit modified version of ProxyFactory taken from Javassist 3.3. This race condition issue has been fixed in Javassist 3.4. In Javassist 3.4 this method has a synchronized block and also weak ref based cache mechanism has been added. The ProxyFactory#createClass() is not thread safe and called from the following 3 methods: 1. Component#getProxyFactory(), this method is a synchronized method 2. ClientSideInterceptor#readResolve() 3. JavaBeanInterceptor#readResolve() 1 and (2 or 3) can run at the same time. Possible options: * Re-sync ProxyFacotory source code with 3.4 or later version * Add a synchronized modifier/block to the ProxyFacotory#createClass() method Exception stack trace: Caused by: org.jboss.seam.InstantiationException: Could not instantiate Seam component: test at org.jboss.seam.Component.newInstance(Component.java:1986) at org.jboss.seam.Component.getInstance(Component.java:1876) at org.jboss.seam.Component.getInstance(Component.java:1843) at org.jboss.seam.Component.getInstanceInAllNamespaces(Component.java:2192) at org.jboss.seam.Component.getValueToInject(Component.java:2144) at org.jboss.seam.Component.injectAttributes(Component.java:1601) at org.jboss.seam.Component.inject(Component.java:1419) at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:45) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:42) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.persistence.EntityManagerProxyInterceptor.aroundInvoke(EntityManagerProxyInterceptor.java:26) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.persistence.HibernateSessionProxyInterceptor.aroundInvoke(HibernateSessionProxyInterceptor.java:27) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) at org.jboss.seam.intercept.SessionBeanInterceptor.aroundInvoke(SessionBeanInterceptor.java:50) 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:585) at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(InvocationContextImpl.java:118) at org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke(EJB3InterceptorsInterceptor.java:63) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.ejb3.entity.TransactionScopedEntityManagerInterceptor.invoke(TransactionScopedEntityManagerInterceptor.java:54) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOperationsInterceptor.java:47) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101) at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:79) ... 184 more Caused by: java.lang.RuntimeException: by java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at org.jboss.seam.util.ProxyFactory.createClass(ProxyFactory.java:190) at org.jboss.seam.Component.createProxyFactory(Component.java:2270) at org.jboss.seam.Component.getProxyFactory(Component.java:1378) at org.jboss.seam.Component.wrap(Component.java:1369) at org.jboss.seam.Component.instantiateSessionBean(Component.java:1291) at org.jboss.seam.Component.instantiate(Component.java:1276) at org.jboss.seam.Component.newInstance(Component.java:1970) ... 212 more Caused by: javassist.CannotCompileException: by java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:165) at org.jboss.seam.util.ProxyFactory.createClass(ProxyFactory.java:186) ... 218 more Caused by: java.lang.LinkageError: duplicate class definition: org/javassist/tmp/java/lang/Object_$$_javassist_95 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:620) at sun.reflect.GeneratedMethodAccessor50.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at javassist.util.proxy.FactoryHelper.toClass2(FactoryHelper.java:177) at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:159) ... 219 more -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira

[ https://jira.jboss.org/jira/browse/JBSEAM-3925?page=com.atlassian.jira.pl... ] Takayoshi Kimura commented on JBSEAM-3925: ------------------------------------------ One more possible problem, the ProxyFactory uses same proxy naming as javassist in the make() method, so these could generate same class name at the same time. // generate a proxy name. classname = classname + "_$$_javassist_" + counter++; Probably it's safe to change something in this class name. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira

[ https://jira.jboss.org/jira/browse/JBSEAM-3925?page=com.atlassian.jira.pl... ] Takayoshi Kimura commented on JBSEAM-3925: ------------------------------------------ Norman, Thanks for quick fix. Any comments/thoughts on my additional comment BTW? I've checked trunk and it still uses same class name format. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira