IllegalStateException:无法覆盖Guava map.put中的原因

Question

我使用创建一个地图

new MapMaker().softValues().maximumSize(cacheSize).makeMap();

这似乎工作正常,但是,在服务器上部署并将新元素放入地图后,我有时会获得以下异常:

java.lang.IllegalStateException: Can't overwrite cause
  at java.lang.Throwable.initCause(Throwable.java:320)
  at org.jboss.mx.loading.RepositoryClassLoader.findClass(RepositoryClassLoader.java:624)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
  at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:474)
  at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:415)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
  at com.google.common.collect.CustomConcurrentHashMap$2.iterator(CustomConcurrentHashMap.java:828)
  at java.util.AbstractCollection.remove(AbstractCollection.java:241)
  at com.google.common.collect.CustomConcurrentHashMap$Segment.removeFromChain(CustomConcurrentHashMap.java:2599)
  at com.google.common.collect.CustomConcurrentHashMap$Segment.processPendingCleanup(CustomConcurrentHashMap.java:2772)
  at com.google.common.collect.CustomConcurrentHashMap$Segment.runLockedCleanup(CustomConcurrentHashMap.java:2860)
  at com.google.common.collect.CustomConcurrentHashMap$Segment.preWriteCleanup(CustomConcurrentHashMap.java:2806)
  at com.google.common.collect.CustomConcurrentHashMap$Segment.put(CustomConcurrentHashMap.java:2374)
  at com.google.common.collect.CustomConcurrentHashMap.put(CustomConcurrentHashMap.java:3346)
  at my.app.cache.CacheImplGoogleGuava.put(CacheImplGoogleGuava.java:36)
...

可能是什么原因？

- - 更新:

JBoss版本是5.

在Throwable.initCause中设置断点, 并显示ClassNotFoundException消息: Invalid use of destroyed classloader for com.google.common.collect.Iterators, UCL destroyed at:和Stacktrace

ClassNotFoundException(Throwable).initCause(Throwable):320
UnifiedClassLoader3(RepositoryClassLoader).findClass(String):628
...
UnifiedClassLoader3(ClassLoader).loadClass(String):248
CustomConcurrentHashMap$2.iterator():828
CustomConcurrentHashMap$2(AbstractCollection<E>).remove(Object):241
CustomConcurrentHashMap$Segment.enqueueCleanup(...):2738
CustomConcurrentHashMap$Segment.unsetValue(...):2662
CustomConcurrentHashMap<K, V>.reclaimValue(...)
CustomConcurrentHashMap$SoftValueReference<K, V>.finalizeReferent():1637
...
Method.invoke:574
Finalizer.claenUp:154
Finalizer.run:127

从堆栈跟踪中,似乎地图中的对象最终确定无法加载finalizeReferent类中的对象com.google.common.collect.Iterators.

Answer 1

你的问题似乎与MapMaker一般的番石榴无关.

您只看到处理另一个异常时发生的异常(不幸的是).

Throwable.initCause()在调用当前已经为当前指定的原因Throwable(通过方法或构造函数`)时抛出异常.

该RepositoryClassLoader.findClass()方法似乎正在处理一些它期望没有原因的异常,但实际上它已经有一个原因集,它触发了这个异常.

不幸的是,你在这里看到的异常隐藏了实际的异常(这对于解决问题可能更为重要).

尝试Throwable.initCause()在第320行或RepositoryClassLoader.findClass()第624行(第624行)放置一个breakpoit 并重现问题(希望)在IDE的局部变量视图中看到"真实"异常.