com.blazebit.persistence.CaseWhenStarterBuilder Maven / Gradle / Ivy
/*
* Copyright 2014 - 2020 Blazebit.
*
* 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.blazebit.persistence;
/**
* A builder for general case when expressions.
*
* @param The builder type that is returned on terminal operations
* @author Christian Beikov
* @since 1.0.0
*/
public interface CaseWhenStarterBuilder {
/**
* Starts a {@link RestrictionBuilder} to create a when predicate where expression will be on the left hand side of the predicate.
*
* @param expression The left hand expression for a when predicate
* @return The restriction builder for the given expression
*/
public RestrictionBuilder>> when(String expression);
/**
* Starts a {@link SubqueryInitiator} for the left hand side of a when predicate.
* When the subquery builder and the restriction builder for the right hand side are finished,
* the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @return The subquery initiator for building a subquery
*/
public SubqueryInitiator>>> whenSubquery();
/**
* Starts a {@link SubqueryInitiator} for the left hand side of a when predicate. All occurrences of subqueryAlias in
* expression will be replaced by the subquery. This allows to build
* expressions containing subqueries like following example shows:
*
*
* {@code whenSubquery("x", "x * 2 + 1").from(Person.class, "p").select("COUNT(p)").end(); }
*
*
*
* results in:
*
*
*
* {@code (SELECT COUNT(p) FROM Person p) * 2 + 1}
*
*
*
* When the subquery builder and the restriction builder for the right hand side are finished, the when predicate in conjunction
* with it's then expression are added to the case when builder.
*
*
* @param subqueryAlias The alias for the subquery which will be replaced by the actual subquery
* @param expression The expression which will be used as left hand side of a predicate.
* This expression contains the {@code subqueryAlias} to define the insertion points for the subquery.
* @return The subquery initiator for building a subquery
*/
public SubqueryInitiator>>> whenSubquery(String subqueryAlias, String expression);
/**
* Starts a {@link SubqueryInitiator} for the left hand side of a when predicate.
*
*
* All occurrences of subsequently defined subqueryAliases in expression will be replaced by the respective subquery.
* When the builder finishes, the resulting expression is used for the left hand side of a when predicate.
*
*
* @param expression The expression which will be used as left hand side of a when predicate
* @return The subquery initiator for building multiple subqueries for their respective subqueryAliases
* @since 1.2.0
*/
public MultipleSubqueryInitiator>>> whenSubqueries(String expression);
/**
* Starts a {@link SubqueryBuilder} based on the given criteria builder for the left hand side of a when predicate.
* When the subquery builder and the restriction builder for the right hand side are finished,
* the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @param criteriaBuilder The criteria builder to base the subquery on
* @return The subquery builder for building a subquery
* @since 1.2.0
*/
public SubqueryBuilder>>> whenSubquery(FullQueryBuilder criteriaBuilder);
/**
* Starts a {@link SubqueryBuilder} based on the given criteria builder for the left hand side of a when predicate. All occurrences of subqueryAlias in
* expression will be replaced by the subquery. This allows to build
* expressions containing subqueries like following example shows:
*
*
* {@code whenSubquery("x", "x * 2 + 1").from(Person.class, "p").select("COUNT(p)").end(); }
*
*
*
* results in:
*
*
*
* {@code (SELECT COUNT(p) FROM Person p) * 2 + 1}
*
*
*
* When the subquery builder and the restriction builder for the right hand side are finished, the when predicate in conjunction
* with it's then expression are added to the case when builder.
*
*
* @param subqueryAlias The alias for the subquery which will be replaced by the actual subquery
* @param expression The expression which will be used as left hand side of a predicate.
* This expression contains the {@code subqueryAlias} to define the insertion points for the subquery.
* @param criteriaBuilder The criteria builder to base the subquery on
* @return The subquery builder for building a subquery
* @since 1.2.0
*/
public SubqueryBuilder>>> whenSubquery(String subqueryAlias, String expression, FullQueryBuilder criteriaBuilder);
/**
* Starts an exists predicate for the when clause with a subquery on the right hand side.
* When the builder finishes, the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @return The subquery initiator for building a subquery
*/
public SubqueryInitiator>> whenExists();
/**
* Starts an exists predicate for the when clause with a subquery on the right hand side.
* When the builder finishes, the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @return The subquery initiator for building a subquery
*/
public SubqueryInitiator>> whenNotExists();
/**
* Starts an exists predicate for the when clause with a subquery on the right hand side based on the given criteria builder.
* When the builder finishes, the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @param criteriaBuilder The criteria builder to base the subquery on
* @return The subquery builder for building a subquery
* @since 1.2.0
*/
public SubqueryBuilder>> whenExists(FullQueryBuilder criteriaBuilder);
/**
* Starts an exists predicate for the when clause with a subquery on the right hand side based on the given criteria builder.
* When the builder finishes, the when predicate in conjunction with it's then expression are added to the case when builder.
*
* @param criteriaBuilder The criteria builder to base the subquery on
* @return The subquery builder for building a subquery
* @since 1.2.0
*/
public SubqueryBuilder>> whenNotExists(FullQueryBuilder criteriaBuilder);
/**
* Starts a {@link CaseWhenAndThenBuilder} which is a predicate consisting only of
* conjunctive connected predicates. When the builder finishes, the when predicate
* in conjunction with it's then expression are added to the case when builder.
*
* @return The and predicate builder for the when expression
*/
public CaseWhenAndThenBuilder> whenAnd();
/**
* Starts a {@link CaseWhenOrThenBuilder} which is a predicate consisting only of
* disjunctiv connected predicates. When the builder finishes, the when predicate
* in conjunction with it's then expression are added to the case when builder.
*
* @return The or predicate builder for the when expression
*/
public CaseWhenOrThenBuilder> whenOr();
}