Package org.astrogrid.samp.xmlrpc

Class ActorHandler

java.lang.Object
org.astrogrid.samp.xmlrpc.ActorHandler
All Implemented Interfaces:
SampXmlRpcHandler
Direct Known Subclasses:
WebHubXmlRpcHandler
public abstract class ActorHandler extends Object implements SampXmlRpcHandler
Utility class to facilitate constructing a SampXmlRpcHandler which handles particular named methods. You supply at construction time an interface which defines the methods to be handled and an object which implements that interface. This object then uses reflection to invoke the correct methods on the implementation object as they are required from incoming XML-RPC execute requests. This insulates the implementation object from having to worry about any XML-RPC specifics.
Since:
15 Jul 2008
Author:
Mark Taylor

  • Constructor Details

    • ActorHandler

      public ActorHandler(String prefix, Class actorType, Object actor)
      Constructor.
      Parameters:
      prefix - string prepended to every method name in the actorType interface to form the XML-RPC methodName element
      actorType - interface defining the XML-RPC methods
      actor - object implementing actorType

  • Method Details

    • canHandleCall

      public boolean canHandleCall(String fqName)
      Description copied from interface: SampXmlRpcHandler
      Returns true if this handler should be able to process given XML-RPC method.
      Specified by:
      canHandleCall in interface SampXmlRpcHandler
      Parameters:
      fqName - method name

    • handleCall

      public Object handleCall(String fqName, List params, Object reqInfo) throws Exception
      Description copied from interface: SampXmlRpcHandler
      Processes an XML-RPC call. This method should only be called if canHandleCall(method) returns true. The params list and the return value must be SAMP-compatible, that is only Strings, Lists and String-keyed Maps are allowed in the data structures. The reqInfo parameter may be used to provide additional information about the XML-RPC request, for instance the originating host; this is implementation specific, and may be null.
      Specified by:
      handleCall in interface SampXmlRpcHandler
      Parameters:
      fqName - XML-RPC method name
      params - XML-RPC parameter list (SAMP-compatible)
      reqInfo - optional additional request information; may be null
      Returns:
      return value (SAMP-compatible)
      Throws:
      Exception

    • getActor

      public Object getActor()
      Returns the implementation object for this handler.
      Returns:
      implementation object

    • invokeMethod

      protected abstract Object invokeMethod(Method method, Object obj, Object[] args) throws IllegalAccessException, InvocationTargetException
      Invokes a method reflectively on an object. This method should be implemented in the obvious way, that is return method.invoke(obj,params).

      If the implementation is effectively prescribed, why is this abstract method here? It's tricky. The reason is so that reflective method invocation from this class is done by code within the actor implementation class itself rather than by code in the superclass, ActorHandler. That in turn means that the actorType class specified in the constructor does not need to be visible from ActorHandler's package, only from the package where the implementation class lives.

      Parameters:
      method - method to invoke
      obj - object to invoke the method on
      args - arguments for the method call
      Throws:
      IllegalAccessException
      InvocationTargetException
      See Also: