| /* |
| * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved. |
| * |
| * 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 com.datatorrent.contrib.couchdb; |
| |
| import org.codehaus.jackson.map.ObjectMapper; |
| import org.ektorp.ViewResult; |
| |
| import java.io.IOException; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * A base CouchDb input adaptor that emits a map. <br/> |
| * <p> |
| * This adaptor coverts the result of a database view to a map and emits it.<br/> |
| * It uses the emitTuples implementation of {@link AbstractCouchDBInputOperator} which emits the complete result |
| * of the ViewQuery every window cycle. |
| * @displayName Abstract Map Based Input |
| * @category Database |
| * @tags input operator |
| * @since 0.3.5 |
| */ |
| public abstract class AbstractMapBasedInputOperator extends AbstractCouchDBInputOperator<Map<Object, Object>> |
| { |
| private transient ObjectMapper mapper; |
| |
| public AbstractMapBasedInputOperator() |
| { |
| mapper = new ObjectMapper(); |
| } |
| |
| @Override |
| @SuppressWarnings("unchecked") |
| public Map<Object, Object> getTuple(ViewResult.Row value) throws IOException |
| { |
| return mapper.readValue(value.getValueAsNode(), HashMap.class); |
| } |
| } |