001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.component.hazelcast.list;
018    
019    import java.util.Map;
020    
021    import com.hazelcast.core.Hazelcast;
022    import com.hazelcast.core.IList;
023    
024    import org.apache.camel.Endpoint;
025    import org.apache.camel.Exchange;
026    import org.apache.camel.Producer;
027    import org.apache.camel.component.hazelcast.HazelcastComponentHelper;
028    import org.apache.camel.component.hazelcast.HazelcastConstants;
029    import org.apache.camel.impl.DefaultProducer;
030    
031    /**
032     * Implementation of Hazelcast List {@link Producer}.
033     */
034    public class HazelcastListProducer extends DefaultProducer {
035    
036        private final IList<Object> list;
037        private final HazelcastComponentHelper helper = new HazelcastComponentHelper();
038    
039        public HazelcastListProducer(Endpoint endpoint, String listName) {
040            super(endpoint);
041            this.list = Hazelcast.getList(listName);
042        }
043    
044        public void process(Exchange exchange) throws Exception {
045    
046            Map<String, Object> headers = exchange.getIn().getHeaders();
047    
048            // get header parameters
049            int operation = -1;
050            Integer pos = null;
051    
052            if (headers.containsKey(HazelcastConstants.OBJECT_POS)) {
053                if (!(headers.get(HazelcastConstants.OBJECT_POS) instanceof Integer)) {
054                    throw new IllegalArgumentException("OBJECT_POS Should be of type Integer");
055                }
056                pos = (Integer) headers.get(HazelcastConstants.OBJECT_POS);
057            }
058    
059            if (headers.containsKey(HazelcastConstants.OPERATION)) {
060                if (headers.get(HazelcastConstants.OPERATION) instanceof String) {
061                    operation = helper.lookupOperationNumber((String) headers.get(HazelcastConstants.OPERATION));
062                } else {
063                    operation = (Integer) headers.get(HazelcastConstants.OPERATION);
064                }
065            }
066    
067            switch (operation) {
068    
069            case HazelcastConstants.ADD_OPERATION:
070                this.add(pos, exchange);
071                break;
072    
073            case HazelcastConstants.GET_OPERATION:
074                this.get(pos, exchange);
075                break;
076    
077            case HazelcastConstants.SETVALUE_OPERATION:
078                this.set(pos, exchange);
079                break;
080    
081            case HazelcastConstants.REMOVEVALUE_OPERATION:
082                this.remove(pos, exchange);
083                break;
084    
085            default:
086                throw new IllegalArgumentException(String.format("The value '%s' is not allowed for parameter '%s' on the LIST cache.", operation, HazelcastConstants.OPERATION));
087            }
088    
089            // finally copy headers
090            HazelcastComponentHelper.copyHeaders(exchange);
091        }
092    
093        private void add(Integer pos, Exchange exchange) {
094            final Object body = exchange.getIn().getBody();
095            if (null == pos) {
096                // add the specified element to the end of the list
097                list.add(body);
098            } else {
099                // add the specified element at the specified position
100                list.add(pos, body);
101            }
102        }
103    
104        private void get(Integer pos, Exchange exchange) {
105            // TODO: this operation is currently not supported by hazelcast
106            exchange.getOut().setBody(this.list.get(pos));
107        }
108    
109        private void set(Integer pos, Exchange exchange) {
110            // TODO: this operation is currently not supported by hazelcast
111            if (null == pos) {
112                throw new IllegalArgumentException("Empty position for set operation.");
113            } else {
114                final Object body = exchange.getIn().getBody();
115                list.set(pos, body);
116            }
117        }
118    
119        private void remove(Integer pos, Exchange exchange) {
120            if (null == pos) {
121                // removes the first occurrence in the list
122                final Object body = exchange.getIn().getBody();
123                list.remove(body);
124            } else {
125                // TODO: this operation is currently not supported by hazelcast
126                // removes the element at the specified position
127                int position = pos;
128                list.remove(position);
129            }
130        }
131    }