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 */
017package org.apache.camel.processor;
018
019import org.apache.camel.AsyncCallback;
020import org.apache.camel.AsyncProcessor;
021import org.apache.camel.Exchange;
022import org.apache.camel.Expression;
023import org.apache.camel.Traceable;
024import org.apache.camel.support.ServiceSupport;
025import org.apache.camel.util.AsyncProcessorHelper;
026
027/**
028 * A processor which sets the property on the exchange with an {@link org.apache.camel.Expression}
029 */
030public class SetPropertyProcessor extends ServiceSupport implements AsyncProcessor, Traceable {
031    private final String propertyName;
032    private final Expression expression;
033
034    public SetPropertyProcessor(String propertyName, Expression expression) {
035        this.propertyName = propertyName;
036        this.expression = expression;
037    }
038
039    public void process(Exchange exchange) throws Exception {
040        AsyncProcessorHelper.process(this, exchange);
041    }
042
043    @Override
044    public boolean process(Exchange exchange, AsyncCallback callback) {
045        try {
046            Object newProperty = expression.evaluate(exchange, Object.class);
047
048            if (exchange.getException() != null) {
049                // the expression threw an exception so we should break-out
050                callback.done(true);
051                return true;
052            }
053
054            exchange.setProperty(propertyName, newProperty);
055        } catch (Throwable e) {
056            exchange.setException(e);
057        }
058
059        callback.done(true);
060        return true;
061    }
062
063    @Override
064    public String toString() {
065        return "SetProperty(" + propertyName + ", " + expression + ")";
066    }
067
068    public String getTraceLabel() {
069        return "setProperty[" + propertyName + ", " + expression + "]";
070    }
071
072    @Override
073    protected void doStart() throws Exception {
074        // noop
075    }
076
077    @Override
078    protected void doStop() throws Exception {
079        // noop
080    }
081}