org.drools.runtime.process.WorkItemHandler Maven / Gradle / Ivy
/**
* Copyright 2010 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.runtime.process;
/**
* A work item handler is responsible for executing work items
* of a specific type. They represent the glue code between an
* abstract, high-level work item that is used inside the process
* and the implementation of this work item. Work item handlers
* should be registered with the WorkItemManager for
* each type of work that can be executed in the engine.
*
* A work item handler is responsible for executing a work item whenever
* the work item manager delegates one to it. It should also notify
* the work item manager when the work item has been completed.
*
* It is also possible that a work item handler is requested to abort
* an existing work item (that is still executing) because it is no longer
* necessary. This might for example be because the process instance
* (or a part of the process instance) that is was executing in is being
* aborted. The work item handler should then try to abort this work item
* (if possible) and if necessary clean up runtime state related to its
* execution.
*
* For example, a work item handler that is responsible for executing
* email work items will retrieve the necessary information from the
* work item (from, to, body, etc.) and invoke the mail server. Afterwards,
* it will notify the WorkItemManager that the work item was completed.
*/
public interface WorkItemHandler {
/**
* The given work item should be executed.
* @param workItem the work item that should be executed
* @param manager the manager that requested the work item to be executed
*/
void executeWorkItem(WorkItem workItem,
WorkItemManager manager);
/**
* The given work item should be aborted.
* @param workItem the work item that should be aborted
* @param manager the manager that requested the work item to be aborted
*/
void abortWorkItem(WorkItem workItem,
WorkItemManager manager);
}