ReverseDataFormat.java

/**
 * 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 camelinaction;

import java.io.InputStream;
import java.io.OutputStream;

import org.apache.camel.Exchange;
import org.apache.camel.spi.DataFormat;

/**
 * A simple custom data format that can reverse strings.
 *
 * @version $Revision$
 */
public class ReverseDataFormat implements DataFormat {

    public void marshal(Exchange exchange, Object graph, OutputStream stream) throws Exception {
        byte[] bytes = exchange.getContext().getTypeConverter().mandatoryConvertTo(byte[].class, graph);
        String body = reverseBytes(bytes);
        stream.write(body.getBytes());
    }

    public Object unmarshal(Exchange exchange, InputStream stream) throws Exception {
        byte[] bytes = exchange.getContext().getTypeConverter().mandatoryConvertTo(byte[].class, stream);
        String body = reverseBytes(bytes);
        return body;
    }

    private String reverseBytes(byte[] data) {
        StringBuilder sb = new StringBuilder(data.length);
        for (int i = data.length - 1; i >= 0; i--) {
            char ch = (char) data[i];
            sb.append(ch);
        }
        return sb.toString();
    }

}