/**
* 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 org.apache.camel.impl.converter;
import java.util.concurrent.Future;
import org.apache.camel.Converter;
import org.apache.camel.Exchange;
import org.apache.camel.NoTypeConversionAvailableException;
import org.apache.camel.StreamCache;
import org.apache.camel.TypeConverter;
import org.apache.camel.util.ExchangeHelper;
import org.apache.camel.util.ObjectHelper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* Future type converter.
*
* @version $Revision: 833413 $
*/
@Converter
public final class FutureTypeConverter implements TypeConverter {
private static final Log LOG = LogFactory.getLog(FutureTypeConverter.class);
private final TypeConverter converter;
public FutureTypeConverter(TypeConverter converter) {
this.converter = converter;
}
@SuppressWarnings("unchecked")
private <T> T doConvertTo(Class<T> type, Exchange exchange, Object value) throws Exception {
// do not convert to stream cache
if (StreamCache.class.isAssignableFrom(value.getClass())) {
return null;
}
if (Future.class.isAssignableFrom(value.getClass())) {
Future future = (Future) value;
if (future.isCancelled()) {
// return void to indicate its not possible to convert at this time
return (T) Void.TYPE;
}
// do some trace logging as the get is blocking until the response is ready
if (LOG.isTraceEnabled()) {
LOG.trace("Getting future response");
}
Object body = future.get();
if (LOG.isTraceEnabled()) {
LOG.trace("Got future response");
}
if (body == null) {
// return void to indicate its not possible to convert at this time
return (T) Void.TYPE;
}
// maybe from is already the type we want
if (type.isAssignableFrom(body.getClass())) {
return type.cast(body);
} else if (body instanceof Exchange) {
Exchange result = (Exchange) body;
body = ExchangeHelper.extractResultBody(result, result.getPattern());
}
// no then try to lookup a type converter
return converter.convertTo(type, exchange, body);
}
return null;
}
public <T> T convertTo(Class<T> type, Object value) {
return convertTo(type, null, value);
}
public <T> T convertTo(Class<T> type, Exchange exchange, Object value) {
try {
return doConvertTo(type, exchange, value);
} catch (Exception e) {
throw ObjectHelper.wrapRuntimeCamelException(e);
}
}
public <T> T mandatoryConvertTo(Class<T> type, Object value) throws NoTypeConversionAvailableException {
return mandatoryConvertTo(type, null, value);
}
public <T> T mandatoryConvertTo(Class<T> type, Exchange exchange, Object value) throws NoTypeConversionAvailableException {
T answer;
try {
answer = doConvertTo(type, exchange, value);
} catch (Exception e) {
throw new NoTypeConversionAvailableException(value, type, e);
}
if (answer == null) {
throw new NoTypeConversionAvailableException(value, type);
}
return answer;
}
}