/**
* 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.converter.dozer;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.camel.CamelContext;
import org.apache.camel.CamelContextAware;
import org.apache.camel.TypeConverter;
import org.apache.camel.spi.ClassResolver;
import org.apache.camel.spi.TypeConverterRegistry;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.dozer.DozerBeanMapper;
import org.dozer.Mapper;
import org.dozer.classmap.ClassMap;
import org.dozer.classmap.MappingFileData;
import org.dozer.config.BeanContainer;
import org.dozer.loader.api.BeanMappingBuilder;
import org.dozer.loader.xml.MappingFileReader;
import org.dozer.loader.xml.XMLParserFactory;
import org.dozer.util.DozerClassLoader;
/**
* <code>DozerTypeConverterLoader</code> provides the mechanism for registering
* a Dozer {@link Mapper} as {@link TypeConverter} for a {@link CamelContext}.
* <p/>
* While a mapper can be explicitly supplied as a parameter the
* {@link CamelContext}'s registry will also be searched for {@link Mapper}
* instances. A {@link DozerTypeConverter} is created to wrap each
* {@link Mapper} instance and the mapper is queried for the types it converts.
* The queried types are used to register the {@link TypeConverter} with the
* context via its {@link TypeConverterRegistry}.
*/
public class DozerTypeConverterLoader implements CamelContextAware {
private final Log log = LogFactory.getLog(getClass());
private CamelContext camelContext;
private DozerBeanMapper mapper;
/**
* Creates a <code>DozerTypeConverter</code> performing no
* {@link TypeConverter} registration.
*/
public DozerTypeConverterLoader() {
}
/**
* Creates a <code>DozerTypeConverter</code> that will search the given
* {@link CamelContext} for instances of {@link DozerBeanMapper}. Each
* discovered instance will be wrapped as a {@link DozerTypeConverter} and
* register as a {@link TypeConverter} with the context
*
* @param camelContext the context to register the
* {@link DozerTypeConverter} in
*/
public DozerTypeConverterLoader(CamelContext camelContext) {
init(camelContext, null);
}
/**
* Creates a <code>DozerTypeConverter</code> that will wrap the the given
* {@link DozerBeanMapper} as a {@link DozerTypeConverter} and register it
* with the given context. It will also search the context for
*
* @param camelContext the context to register the
* {@link DozerTypeConverter} in
* @param mapper the DozerMapperBean to be wrapped as a type converter.
*/
public DozerTypeConverterLoader(CamelContext camelContext, DozerBeanMapper mapper) {
init(camelContext, mapper);
}
/**
* Doses the actual querying and registration of {@link DozerTypeConverter}s
* with the {@link CamelContext}.
*
* @param camelContext the context to register the
* {@link DozerTypeConverter} in
* @param mapper the DozerMapperBean to be wrapped as a type converter.
*/
public void init(CamelContext camelContext, DozerBeanMapper mapper) {
this.camelContext = camelContext;
this.mapper = mapper;
CamelToDozerClassResolverAdapter adapter = new CamelToDozerClassResolverAdapter(camelContext);
BeanContainer.getInstance().setClassLoader(adapter);
Map<String, DozerBeanMapper> mappers = new HashMap<String, DozerBeanMapper>(camelContext.getRegistry().lookupByType(DozerBeanMapper.class));
if (mapper != null) {
mappers.put("parameter", mapper);
}
if (mappers.size() > 1) {
log.warn("Loaded " + mappers.size() + " Dozer mappers from Camel registry."
+ " Dozer is most efficient when there is a single mapper instance. Consider amalgamating instances.");
} else if (mappers.size() == 0) {
log.warn("No Dozer mappers found in Camel registry. You should add Dozer mappers as beans to the registry of the type: "
+ DozerBeanMapper.class.getName());
}
TypeConverterRegistry registry = camelContext.getTypeConverterRegistry();
for (DozerBeanMapper dozer : mappers.values()) {
List<ClassMap> all = loadMappings(camelContext, dozer);
registerClassMaps(registry, dozer, all);
}
}
private void registerClassMaps(TypeConverterRegistry registry, DozerBeanMapper dozer, List<ClassMap> all) {
DozerTypeConverter converter = new DozerTypeConverter(dozer);
for (ClassMap map : all) {
if (log.isInfoEnabled()) {
log.info("Added " + map.getSrcClassName() + " -> " + map.getDestClassName() + " as type converter to: " + registry);
}
registry.addTypeConverter(map.getSrcClassToMap(), map.getDestClassToMap(), converter);
registry.addTypeConverter(map.getDestClassToMap(), map.getSrcClassToMap(), converter);
}
}
private List<ClassMap> loadMappings(CamelContext camelContext, DozerBeanMapper mapper) {
List<ClassMap> answer = new ArrayList<ClassMap>();
// load the class map using the class resolver so we can load from classpath in OSGi
MappingFileReader reader = new MappingFileReader(XMLParserFactory.getInstance());
List<String> mappingFiles = mapper.getMappingFiles();
if (mappingFiles == null) {
return Collections.emptyList();
}
for (String name : mappingFiles) {
URL url = camelContext.getClassResolver().loadResourceAsURL(name);
MappingFileData data = reader.read(url);
answer.addAll(data.getClassMaps());
}
return answer;
}
/**
* Registers Dozer <code>BeanMappingBuilder</code> in current mapper instance.
* This method should be called instead of direct <code>mapper.addMapping()</code> invocation for Camel
* being able to register given type conversion.
*
* @param beanMappingBuilder api-based mapping builder
*/
public void addMapping(BeanMappingBuilder beanMappingBuilder) {
if (mapper == null) {
log.warn("No mapper instance provided to " + this.getClass().getSimpleName()
+ ". Mapping has not been registered!");
return;
}
mapper.addMapping(beanMappingBuilder);
MappingFileData mappingFileData = beanMappingBuilder.build();
TypeConverterRegistry registry = camelContext.getTypeConverterRegistry();
ArrayList<ClassMap> classMaps = new ArrayList<ClassMap>();
classMaps.addAll(mappingFileData.getClassMaps());
registerClassMaps(registry, mapper, classMaps);
}
public CamelContext getCamelContext() {
return camelContext;
}
public void setCamelContext(CamelContext camelContext) {
init(camelContext, null);
}
private static final class CamelToDozerClassResolverAdapter implements DozerClassLoader {
private final ClassResolver classResolver;
private CamelToDozerClassResolverAdapter(CamelContext camelContext) {
classResolver = camelContext.getClassResolver();
}
public Class<?> loadClass(String s) {
return classResolver.resolveClass(s);
}
public URL loadResource(String s) {
URL url = classResolver.loadResourceAsURL(s);
if (url == null) {
// using the classloader of DozerClassLoader as a fallback
url = DozerClassLoader.class.getClassLoader().getResource(s);
}
return url;
}
}
}