/**
* 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.metamodel.factory;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.ServiceLoader;
import org.apache.metamodel.util.Resource;
public class ResourceFactoryRegistryImpl implements ResourceFactoryRegistry {
private static final ResourceFactoryRegistry DEFAULT_INSTANCE;
static {
final ResourceFactoryRegistryImpl registry = new ResourceFactoryRegistryImpl();
registry.discoverFromClasspath();
DEFAULT_INSTANCE = registry;
}
public static ResourceFactoryRegistry getDefaultInstance() {
return DEFAULT_INSTANCE;
}
private final List<ResourceFactory> factories;
public ResourceFactoryRegistryImpl() {
factories = new ArrayList<>();
}
@Override
public void addFactory(ResourceFactory factory) {
factories.add(factory);
}
@Override
public void clearFactories() {
factories.clear();
}
@Override
public Collection<ResourceFactory> getFactories() {
return Collections.unmodifiableList(factories);
}
@Override
public Resource createResource(ResourceProperties properties) {
for (ResourceFactory factory : factories) {
if (factory.accepts(properties)) {
return factory.create(properties);
}
}
throw new UnsupportedResourcePropertiesException();
}
public void discoverFromClasspath() {
final ServiceLoader<ResourceFactory> serviceLoader = ServiceLoader.load(ResourceFactory.class);
for (ResourceFactory factory : serviceLoader) {
addFactory(factory);
}
}
}