/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.uima.flow;

import java.util.Map;

import org.apache.uima.UimaContext;
import org.apache.uima.analysis_engine.metadata.AnalysisEngineMetaData;

/**
 * A subtype of {@link UimaContext} used by {@link FlowController} components. In addition to access
 * to resources and configuration settings (provided by <code>UimaContext</code>), the
 * <code>FlowControllerContext</code> provides access to other information that the FlowController
 * can use to make routing decisions. This includes:
 * <ul>
 * <li>A map from AnalysisEngine key to AnalysisEngineMetaData for all AnalysisEngines that the
 * FlowController can route CASes to</li>
 * <li>Declared Capabilities of the Aggregate AnalysisEngine containing this FlowController.</li>
 * </ul>
 */
public interface FlowControllerContext extends UimaContext {
  /**
   * Gets a map from Analysis Engine key (a String) to {@link AnalysisEngineMetaData}. This map
   * contains an entry for all Analysis Engines to which the FlowController can route CASes.
   * 
   * @return a map with <code>String</code> keys, and {@link AnalysisEngineMetaData} values
   */
  Map<String, AnalysisEngineMetaData> getAnalysisEngineMetaDataMap();

  /**
   * Gets the metadata of the Aggregate AnalysisEngine containing this FlowController. This includes
   * the specification of the inputs and outputs of the aggregate, which may be useful for some
   * FlowController implementations.
   * 
   * @return the Capabilities of the aggregate containing this FlowController.
   */
  AnalysisEngineMetaData getAggregateMetadata();
}
