/*
* Copyright 2008-2020 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
*
* https://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.domain;
import static org.springframework.data.jpa.domain.SpecificationComposition.*;
import java.io.Serializable;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;
import org.springframework.lang.Nullable;
Specification in the sense of Domain Driven Design.
Author: Oliver Gierke, Thomas Darimont, Krzysztof Rzymkowski, Sebastian Staudt, Mark Paluch
/**
* Specification in the sense of Domain Driven Design.
*
* @author Oliver Gierke
* @author Thomas Darimont
* @author Krzysztof Rzymkowski
* @author Sebastian Staudt
* @author Mark Paluch
*/
public interface Specification<T> extends Serializable {
long serialVersionUID = 1L;
Negates the given Specification
. Params: - spec – can be null.
Type parameters: - <T> –
Returns: Since: 2.0
/**
* Negates the given {@link Specification}.
*
* @param <T>
* @param spec can be {@literal null}.
* @return
* @since 2.0
*/
static <T> Specification<T> not(@Nullable Specification<T> spec) {
return spec == null //
? (root, query, builder) -> null//
: (root, query, builder) -> builder.not(spec.toPredicate(root, query, builder));
}
Simple static factory method to add some syntactic sugar around a Specification
. Params: - spec – can be null.
Type parameters: - <T> –
Returns: Since: 2.0
/**
* Simple static factory method to add some syntactic sugar around a {@link Specification}.
*
* @param <T>
* @param spec can be {@literal null}.
* @return
* @since 2.0
*/
@Nullable
static <T> Specification<T> where(@Nullable Specification<T> spec) {
return spec == null ? (root, query, builder) -> null : spec;
}
ANDs the given Specification
to the current one. Params: - other – can be null.
Returns: The conjunction of the specifications Since: 2.0
/**
* ANDs the given {@link Specification} to the current one.
*
* @param other can be {@literal null}.
* @return The conjunction of the specifications
* @since 2.0
*/
@Nullable
default Specification<T> and(@Nullable Specification<T> other) {
return composed(this, other, (builder, left, rhs) -> builder.and(left, rhs));
}
ORs the given specification to the current one.
Params: - other – can be null.
Returns: The disjunction of the specifications Since: 2.0
/**
* ORs the given specification to the current one.
*
* @param other can be {@literal null}.
* @return The disjunction of the specifications
* @since 2.0
*/
@Nullable
default Specification<T> or(@Nullable Specification<T> other) {
return composed(this, other, (builder, left, rhs) -> builder.or(left, rhs));
}
Creates a WHERE clause for a query of the referenced entity in form of a Predicate
for the given Root
and CriteriaQuery
. Params: - root – must not be null.
- query – must not be null.
- criteriaBuilder – must not be null.
Returns: a Predicate
, may be null.
/**
* Creates a WHERE clause for a query of the referenced entity in form of a {@link Predicate} for the given
* {@link Root} and {@link CriteriaQuery}.
*
* @param root must not be {@literal null}.
* @param query must not be {@literal null}.
* @param criteriaBuilder must not be {@literal null}.
* @return a {@link Predicate}, may be {@literal null}.
*/
@Nullable
Predicate toPredicate(Root<T> root, CriteriaQuery<?> query, CriteriaBuilder criteriaBuilder);
}