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Scopes in WARs

Justin Chu
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Joined: Apr 19, 2002
Posts: 209
Is it ok to have different versions of the same class in different WARs?
If I implement a singleton object, will they be the same object when called from different WARS?
Junaid Bhatra
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Joined: Jun 27, 2000
Posts: 213
Generally different .wars are loaded by separate classloaders. Hence there will be multiple (and incompatible) copies of any common classes present in those wars. For eg, a singleton won't really be a singleton, and each war will load it's own copy of the class.
If you truly want, say a singleton, it should be present up the classloader hierarchy. This can be achieved by placing it in the classpath. This is generally how containers load classes, although there's no guarantee.
I agree. Here's the link:
subject: Scopes in WARs