jaxb.java
/*
* Java Genetic Algorithm Library (@__identifier__@).
* Copyright (c) @__year__@ Franz Wilhelmstötter
*
* Licensed 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.
*
* Author:
* Franz Wilhelmstötter (franz.wilhelmstoetter@gmx.at)
*/
package org.jenetics.internal.util;
import static org.jenetics.internal.util.reflect.classOf;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.bind.DataBindingException;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.annotation.adapters.XmlAdapter;
import org.jenetics.internal.util.model.CharacterModel;
import org.jenetics.util.Function;
import org.jenetics.util.StaticObject;
/**
* JAXB helper methods.
*
* @author <a href="mailto:franz.wilhelmstoetter@gmx.at">Franz Wilhelmstötter</a>
* @version 1.6 — <em>$Date: 2014-04-12 $</em>
* @since 2.0
*/
public class jaxb extends StaticObject {
private jaxb() {}
private static final class JAXBContextHolder {
private static final JAXBContext CONTEXT; static {
try {
CONTEXT = JAXBContext.newInstance(
"org.jenetics:org.jenetics.internal.util"
);
} catch (JAXBException e) {
throw new DataBindingException(
"Something went wrong while creating JAXBContext.", e
);
}
}
}
public static JAXBContext context() {
return JAXBContextHolder.CONTEXT;
}
private static final XmlAdapter<Object, Object> IdentityAdapter =
new XmlAdapter<Object, Object>() {
@Override public Object unmarshal(final Object value) {
return value;
}
@Override public Object marshal(final Object value) {
return value;
}
};
private static final Map<Class<?>, XmlAdapter<?, ?>> ADAPTERS = new HashMap<>();
static {
ADAPTERS.put(Character.class, CharacterModel.ADAPTER);
ADAPTERS.put(CharacterModel.class, CharacterModel.ADAPTER);
}
/**
* Return the an {@code XmlAdapter} for the given {@code vale}. If no
* adapter could be found, and identity adapter is returned.
*
* @param value the object for which to find an {@code XmlAdapter}
* @return the {@code XmlAdapter} for the given object, or an identity
* adapter if no one can be found.
*/
@SuppressWarnings("unchecked")
public static XmlAdapter<Object, Object> adapterFor(final Object value) {
final Class<?> cls = classOf(value);
synchronized (ADAPTERS) {
if (!ADAPTERS.containsKey(cls)) {
ADAPTERS.put(cls, newXmlAdapter(cls));
}
return (XmlAdapter<Object, Object>) ADAPTERS.get(cls);
}
}
@SuppressWarnings("unchecked")
private static XmlAdapter<Object, Object> newXmlAdapter(final Class<?> cls) {
final List<Class<?>> classes = reflect.allDeclaredClasses(cls);
XmlAdapter<Object, Object> adapter = IdentityAdapter;
for (int i = 0; i < classes.size() && adapter == IdentityAdapter; ++i) {
if (XmlAdapter.class.isAssignableFrom(classes.get(i))) {
try {
adapter = (XmlAdapter<Object, Object>)classes.get(i).newInstance();
} catch (InstantiationException | IllegalAccessException e) {
// ignore exception
}
}
}
return adapter;
}
/**
* Shorthand for {@code adapterFor(value).marshal(value)}
*/
public static Object marshal(final Object value) throws Exception {
return adapterFor(value).marshal(value);
}
/**
* Shorthand for {@code adapterFor(value).unmarshal(value)}
*/
public static Object unmarshal(final Object value) throws Exception {
return adapterFor(value).unmarshal(value);
}
/**
* Return a marshaller function from the given
* {@link javax.xml.bind.annotation.adapters.XmlAdapter}.
*
* @param a the adapter used by the marshaller function.
* @return the marshaller function
*/
public static <V, B> Function<B, V> Marshaller(final XmlAdapter<V, B> a) {
return new Function<B, V>() {
@Override
public V apply(final B value) {
try {
return a.marshal(value);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
};
}
/**
* Return a unmarshaller function from the given
* {@link javax.xml.bind.annotation.adapters.XmlAdapter}.
*
* @param a the adapter used by the unmarshaller function.
* @return the unmarshaller function
*/
public static <V, B> Function<V, B> Unmarshaller(final XmlAdapter<V, B> a) {
return new Function<V, B>() {
@Override
public B apply(final V value) {
try {
return a.unmarshal(value);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
};
}
/**
* Return a marshaller function for the given object.
*
* @param value the value to marshal
* @return the marshaller function
*/
public static Function<Object, Object> Marshaller(final Object value) {
return Marshaller(adapterFor(value));
}
/**
* Return a unmarshaller function for the given object.
*
* @param value the value to unmarshal
* @return the unmarshaller function
*/
public static Function<Object, Object> Unmarshaller(final Object value) {
return Unmarshaller(jaxb.adapterFor(value));
}
}