| A service which can assemble an implementation based on a command interface, and an ordered list
of objects implementing that interface (the "commands"). This is an implementation of the Gang of
Four Chain Of Command pattern.
For each method in the interface, the chain implementation will call the corresponding method on
each command object in turn (with the order defined by the list). If any of the command objects
return true, then the chain of command stops and the initial method invocation returns true.
Otherwise, the chain of command continues to the next command (and will return false if none of
the commands returns true).
For methods whose return type is not boolean, the chain stops with the first non-null (for object
types), or non-zero (for numeric types). The chain returns the value that was returned by the
command. If the method return type is void, all commands will be invoked.
Method invocations will also be terminated if an exception is thrown.
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