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An interceptor that copies all the properties of every object in the value stack to the currently executing object, except for any object that implements Unchainable. A collection of optional
excludes may be provided to control how and which parameters are copied. Only
excludes may be specified. Specifying both results in undefined behavior. See the javadocs for ReflectionProvider#copy(Object, Object, java.util.Map, java.util.Collection, java.util.Collection) for more information.
It is important to remember that this interceptor does nothing if there are no objects already on the stack. This means two things:
By default Errors, Field errors and Message aren't copied during chaining, to change the behaviour you can specify the below three constants in struts.properties or struts.xml:
struts.xwork.chaining.copyErrors- set to true to copy Action Errors
struts.xwork.chaining.copyFieldErrors- set to true to copy Field Errors
struts.xwork.chaining.copyMessages- set to true to copy Action Messages
excludes(optional) - the list of parameter names to exclude from copying (all others will be included)
includes(optional) - the list of parameter names to include when copying (all others will be excluded)
There are no known extension points to this interceptor.
Simple example how to chain two actions
This examples chains two actions but only one property from first action is copied to another