JpaSpecificationExecutor.java

/*
 * Copyright 2008-2011 the original author or authors.
 *
 * 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 org.springframework.data.jpa.repository;

import java.util.List;

import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.jpa.domain.Specification;

/**
 * Interface to allow execution of {@link Specification}s based on the JPA criteria API.
 * 
 * @author Oliver Gierke
 */
public interface JpaSpecificationExecutor<T> {

	/**
	 * Returns a single entity matching the given {@link Specification}.
	 * 
	 * @param spec
	 * @return
	 */
	T findOne(Specification<T> spec);

	/**
	 * Returns all entities matching the given {@link Specification}.
	 * 
	 * @param spec
	 * @return
	 */
	List<T> findAll(Specification<T> spec);

	/**
	 * Returns a {@link Page} of entities matching the given {@link Specification}.
	 * 
	 * @param spec
	 * @param pageable
	 * @return
	 */
	Page<T> findAll(Specification<T> spec, Pageable pageable);

	/**
	 * Returns all entities matching the given {@link Specification} and {@link Sort}.
	 * 
	 * @param spec
	 * @param sort
	 * @return
	 */
	List<T> findAll(Specification<T> spec, Sort sort);

	/**
	 * Returns the number of instances that the given {@link Specification} will return.
	 * 
	 * @param spec the {@link Specification} to count instances for
	 * @return the number of instances
	 */
	long count(Specification<T> spec);
}