/*
* JBoss, Home of Professional Open Source
* Copyright 2009 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.commands;
import org.infinispan.context.InvocationContext;
import org.infinispan.remoting.responses.ResponseGenerator;
import org.jgroups.blocks.MessageRequest;
/**
* The core of the command-based cache framework. Commands correspond to specific areas of functionality in the cache,
* and can be replicated using the {@link org.infinispan.remoting.rpc.RpcManager}
*
* @author Mircea.Markus@jboss.com
* @author Manik Surtani
* @since 4.0
*/
public interface ReplicableCommand {
/**
* Performs the primary function of the command. Please see specific implementation classes for details on what is
* performed as well as return types. <b>Important</b>: this method will be invoked at the end of interceptors chain.
* It should never be called directly from a custom interceptor.
*
* @param ctx invocation context
* @return arbitrary return value generated by performing this command
* @throws Throwable in the event of problems.
*/
Object perform(InvocationContext ctx) throws Throwable;
/**
* Used by marshallers to convert this command into an id for streaming.
*
* @return the method id of this command. This is compatible with pre-2.2.0 MethodCall ids.
*/
byte getCommandId();
/**
* Used by marshallers to stream this command across a network
*
* @return an object array of arguments, compatible with pre-2.2.0 MethodCall args.
*/
Object[] getParameters();
/**
* Used by the {@link CommandsFactory} to create a command from raw data read off a stream.
*
* @param commandId command id to set. This is usually unused but *could* be used in the event of a command having
* multiple IDs, such as {@link org.infinispan.commands.write.PutKeyValueCommand}.
* @param parameters object array of args
*/
void setParameters(int commandId, Object[] parameters);
/**
* If true, a return value will be provided when performed remotely. Otherwise, a remote {@link org.infinispan.remoting.responses.ResponseGenerator}
* may choose to simply return null to save on marshalling costs.
* @return true or false
*/
boolean isReturnValueExpected();
}