I think Struts Action class is not Thread Safe
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Thanks

as my nowladge Actionclass is thread safe.

Struts 1 Actions are singletons and must be thread-safe
since there will only be one instance of a class to handle
all requests for that Action. The singleton strategy places
restrictions on what can be done with Struts 1 Actions and
requires extra care to develop. Action resources must be
thread-safe or synchronized.


Struts 2 Action objects are instantiated for each request,
so there are no thread-safety issues. (In practice, servlet
containers generate many throw-away objects per request, and
one more object does not impose a performance penalty or
impact garbage collection.)

Yes struts is not only thread safe but also thread 
dependent.Because its run in light weigth component and 
from the orignial action class.

Yes struts is threadsafe. and light weight component also