/*
* Copyright 2018-2020 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.repository.query;
import java.util.List;
import org.springframework.lang.Nullable;
import org.springframework.util.StringUtils;
A wrapper for a String representation of a query offering information about the query.
Author: Jens Schauder Since: 2.0.3
/**
* A wrapper for a String representation of a query offering information about the query.
*
* @author Jens Schauder
* @since 2.0.3
*/
interface DeclaredQuery {
Creates a DeclaredQuery from a query String. Params: - query – might be null or empty.
Returns: a DeclaredQuery instance even for a null or empty argument.
/**
* Creates a {@literal DeclaredQuery} from a query {@literal String}.
*
* @param query might be {@literal null} or empty.
* @return a {@literal DeclaredQuery} instance even for a {@literal null} or empty argument.
*/
static DeclaredQuery of(@Nullable String query) {
return StringUtils.isEmpty(query) ? EmptyDeclaredQuery.EMPTY_QUERY : new StringQuery(query);
}
Returns: whether the underlying query has at least one named parameter.
/**
* @return whether the underlying query has at least one named parameter.
*/
boolean hasNamedParameter();
Returns the query string.
/**
* Returns the query string.
*/
String getQueryString();
Returns the main alias used in the query.
Returns: the alias
/**
* Returns the main alias used in the query.
*
* @return the alias
*/
@Nullable
String getAlias();
Returns whether the query is using a constructor expression.
Since: 1.10
/**
* Returns whether the query is using a constructor expression.
*
* @since 1.10
*/
boolean hasConstructorExpression();
Returns whether the query uses the default projection, i.e. returns the main alias defined for the query.
/**
* Returns whether the query uses the default projection, i.e. returns the main alias defined for the query.
*/
boolean isDefaultProjection();
Returns the ParameterBinding
s registered. /**
* Returns the {@link StringQuery.ParameterBinding}s registered.
*/
List<StringQuery.ParameterBinding> getParameterBindings();
Creates a new DeclaredQuery representing a count query, i.e. a query returning the number of rows to be expected from the original query, either derived from the query wrapped by this instance or from the information passed as arguments. Params: - countQuery – an optional query string to be used if present.
- countQueryProjection – an optional return type for the query.
Returns: a new DeclaredQuery instance.
/**
* Creates a new {@literal DeclaredQuery} representing a count query, i.e. a query returning the number of rows to be
* expected from the original query, either derived from the query wrapped by this instance or from the information
* passed as arguments.
*
* @param countQuery an optional query string to be used if present.
* @param countQueryProjection an optional return type for the query.
* @return a new {@literal DeclaredQuery} instance.
*/
DeclaredQuery deriveCountQuery(@Nullable String countQuery, @Nullable String countQueryProjection);
Returns: whether paging is implemented in the query itself, e.g. using SpEL expressions. Since: 2.0.6
/**
* @return whether paging is implemented in the query itself, e.g. using SpEL expressions.
* @since 2.0.6
*/
default boolean usesPaging() {
return false;
}
Returns whether the query uses JDBC style parameters, i.e. parameters denoted by a simple ? without any index or
name.
Returns: Whether the query uses JDBC style parameters. Since: 2.0.6
/**
* Returns whether the query uses JDBC style parameters, i.e. parameters denoted by a simple ? without any index or
* name.
*
* @return Whether the query uses JDBC style parameters.
* @since 2.0.6
*/
boolean usesJdbcStyleParameters();
}