| /** |
| * 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 com.datatorrent.contrib.couchbase; |
| |
| import java.util.ArrayList; |
| |
| import javax.validation.constraints.NotNull; |
| |
| import org.apache.hadoop.classification.InterfaceStability.Evolving; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.datatorrent.lib.util.PojoUtils; |
| import com.datatorrent.lib.util.PojoUtils.Getter; |
| |
| /** |
| * An implementation of Couchbase Output Operator which takes a POJO,serializes it into key,value |
| * pair and then writes to couchbase. |
| * |
| * @displayName Couchbase Output Operator |
| * @category Output |
| * @tags database, nosql, pojo, couchbase |
| * @since 3.0.0 |
| */ |
| @Evolving |
| public class CouchbasePOJOSetOperator extends AbstractCouchBaseSetOperator<Object> |
| { |
| private static final Logger logger = LoggerFactory.getLogger(CouchBaseStore.class); |
| //Key stored in couchbase is always a string. |
| private transient Getter<Object, String> keyGetter; |
| //Value stored in Couchbase can be of these data types: boolean,numeric,string,arrays,object,null. |
| private transient Getter<Object, ? extends Object> valueGetter; |
| @NotNull |
| private ArrayList<String> expressions; |
| |
| /* |
| * An ArrayList of Java expressions that will yield the field value from the POJO. |
| * Each expression corresponds to one column in the Couchbase table. |
| */ |
| public ArrayList<String> getExpressions() |
| { |
| return expressions; |
| } |
| |
| public void setExpressions(ArrayList<String> expressions) |
| { |
| this.expressions = expressions; |
| } |
| |
| @Override |
| public String getKey(Object tuple) |
| { |
| // first tuple |
| if (null == keyGetter) { |
| Class<?> tupleClass = tuple.getClass(); |
| keyGetter = PojoUtils.createGetter(tupleClass, expressions.get(0), String.class); |
| } |
| String key = keyGetter.get(tuple); |
| logger.debug("key is {}", key); |
| return key; |
| } |
| |
| @Override |
| public Object getValue(Object tuple) |
| { |
| Object value = null; |
| if (null == valueGetter) { |
| Class<?> tupleClass = tuple.getClass(); |
| final String getterExpression = expressions.get(1); |
| valueGetter = PojoUtils.createGetter(tupleClass, getterExpression, Object.class); |
| } |
| if (valueGetter != null) { |
| value = valueGetter.get(tuple); |
| } |
| logger.debug("value is {}", value); |
| return value; |
| } |
| |
| } |