org.aspectj.weaver.bcel
Class BcelWeakClassLoaderReference

java.lang.Object
  org.aspectj.weaver.WeakClassLoaderReference
      org.aspectj.weaver.bcel.BcelWeakClassLoaderReference

All Implemented Interfaces:

ClassLoaderReference

public class BcelWeakClassLoaderReference
extends WeakClassLoaderReference
implements ClassLoaderReference

Wraps a reference to a classloader inside a WeakReference. This should be used where we do not want the existence of a classloader reference to prevent garbage collection of that classloader (and possibly an associated weaver instance in the case of load time weaving).

In more detail:
When load time weaving, the class Aj maintains a WeakHashMap from the classloader instance to a weaver instance. The aim is that the weaver is around as long as the classloader is and should the classloader be dereferenced then the weaver can also be garbage collected. The problem is that if there are many references to the classloader from within the weaver, these are considered hard references and cause the classloader to be long lived - even if the user of the classloader has dereferenced it in their code. The solution is that the weaver should use instances of WeakClassLoaderReference objects - so that when the users hard reference to the classloader goes, nothing in the weaver will cause it to hang around. There is a big assertion here that the WeakClassLoaderReference instances will not 'lose' their ClassLoader references until the top level ClassLoader reference is null'd. This means there is no need to check for the null case on get() in this WeakReference logic below, because we shouldn't be using this weaver if its associated ClassLoader has been collected. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=210470

Field Summary

Fields inherited from class org.aspectj.weaver.WeakClassLoaderReference

hashcode

Constructor Summary

BcelWeakClassLoaderReference(java.lang.ClassLoader loader)

Method Summary

boolean

equals(java.lang.Object obj)

Methods inherited from class org.aspectj.weaver.WeakClassLoaderReference

getClassLoader, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.aspectj.apache.bcel.util.ClassLoaderReference

getClassLoader

Constructor Detail

BcelWeakClassLoaderReference

public BcelWeakClassLoaderReference(java.lang.ClassLoader loader)

Method Detail

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class WeakClassLoaderReference