CompositeEntityResolver.java

/*
 * #%L
 * FlatPack serialization code
 * %%
 * Copyright (C) 2012 Perka 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.
 * #L%
 */
package com.getperka.flatpack.inject;

import java.util.Collection;
import java.util.UUID;

import com.getperka.flatpack.HasUuid;
import com.getperka.flatpack.ext.EntityResolver;

/**
 * Aggregates all user-provided resolvers into a single instance.
 */
class CompositeEntityResolver implements EntityResolver {

  private final Collection<EntityResolver> resolvers;

  CompositeEntityResolver(Collection<EntityResolver> resolvers) {
    this.resolvers = resolvers;
  }

  @Override
  public <T extends HasUuid> T resolve(Class<T> clazz, UUID uuid) throws Exception {
    for (EntityResolver resolver : resolvers) {
      T toReturn = resolver.resolve(clazz, uuid);
      if (toReturn != null) {
        return toReturn;
      }
    }
    return null;
  }
}