/*
* Copyright 2010 Google Inc.
*
* 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.
*/
package com.google.gwt.autobean.server.impl;
import com.google.gwt.autobean.server.Configuration;
import com.google.gwt.autobean.shared.AutoBean.PropertyName;
import com.google.gwt.autobean.shared.AutoBeanFactory;
import com.google.gwt.autobean.shared.AutoBeanUtils;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
/**
* Handles dispatches on AutoBeanFactory interfaces.
*
* <p><span style='color:red'>AutoBeans has moved to
* <code>com.google.web.bindery.autobeans</code>. This package will be
* removed in a future version of GWT.</span></p>
*/
@Deprecated
public class FactoryHandler implements InvocationHandler {
private final Configuration configuration;
/**
* Constructor.
*
* @param categories the classes specified by a Category annotation
*/
public FactoryHandler(Configuration configuration) {
this.configuration = configuration;
}
/**
* Handles both declared factory methods as well as the dynamic create
* methods.
*/
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
Class<?> beanType;
Object toWrap = null;
String name = method.getName();
if (name.equals("create")) {
// Dynamic create. Guaranteed to have at least one argument
// create(clazz); or create(clazz, toWrap);
beanType = (Class<?>) args[0];
if (args.length == 2) {
toWrap = args[1];
}
} else if (name.equals("getEnum")) {
Class<?> clazz = (Class<?>) args[0];
String token = (String) args[1];
return getEnum(clazz, token);
} else if (name.equals("getToken")) {
Enum<?> e = (Enum<?>) args[0];
return getToken(e);
} else {
// Declared factory method, use the parameterization
// AutoBean<Foo> foo(); or Autobean<foo> foo(Foo toWrap);
ParameterizedType returnType = (ParameterizedType) method.getGenericReturnType();
beanType = (Class<?>) returnType.getActualTypeArguments()[0];
if (args != null && args.length == 1) {
toWrap = args[0];
}
}
// Return any existing wrapper
ProxyAutoBean<Object> toReturn = (ProxyAutoBean<Object>) AutoBeanUtils.getAutoBean(toWrap);
if (toReturn == null) {
// Create the implementation bean
if (toWrap == null) {
toReturn = new ProxyAutoBean<Object>((AutoBeanFactory) proxy, beanType,
configuration);
} else {
toReturn = new ProxyAutoBean<Object>((AutoBeanFactory) proxy, beanType,
configuration, toWrap);
}
}
return toReturn;
}
/**
* EnumMap support.
*/
private Object getEnum(Class<?> clazz, String token)
throws IllegalAccessException {
for (Field f : clazz.getFields()) {
String fieldName;
PropertyName annotation = f.getAnnotation(PropertyName.class);
if (annotation != null) {
fieldName = annotation.value();
} else {
fieldName = f.getName();
}
if (token.equals(fieldName)) {
f.setAccessible(true);
return f.get(null);
}
}
throw new IllegalArgumentException("Cannot find enum " + token
+ " in type " + clazz.getCanonicalName());
}
/**
* EnumMap support.
*/
private Object getToken(Enum<?> e) throws NoSuchFieldException {
// Remember enum constants are fields
PropertyName annotation = e.getDeclaringClass().getField(e.name()).getAnnotation(
PropertyName.class);
if (annotation != null) {
return annotation.value();
} else {
return e.name();
}
}
}