org.springframework.data.gemfire.repository.query.StringBasedGemfireRepositoryQuery Maven / Gradle / Ivy
/*
* Copyright 2012-2020 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.gemfire.repository.query;
import static org.springframework.data.gemfire.util.CollectionUtils.nullSafeSize;
import static org.springframework.data.gemfire.util.RuntimeExceptionFactory.newIllegalStateException;
import java.util.Collection;
import java.util.Collections;
import org.apache.geode.cache.query.SelectResults;
import org.springframework.dao.IncorrectResultSizeDataAccessException;
import org.springframework.data.gemfire.GemfireTemplate;
import org.springframework.data.repository.Repository;
import org.springframework.data.repository.query.ParametersParameterAccessor;
import org.springframework.data.repository.query.QueryMethod;
import org.springframework.data.repository.query.RepositoryQuery;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;
/**
* {@link GemfireRepositoryQuery} using plain {@link String} based OQL queries.
*
* @author Oliver Gierke
* @author David Turanski
* @author John Blum
*/
public class StringBasedGemfireRepositoryQuery extends GemfireRepositoryQuery {
private static final String INVALID_QUERY = "Paging and modifying queries are not supported";
private boolean userDefinedQuery = false;
private final GemfireTemplate template;
private final QueryString query;
/*
* (non-Javadoc)
* Constructor used for testing purposes only!
*/
StringBasedGemfireRepositoryQuery() {
this.query = null;
this.template = null;
register(ProvidedQueryPostProcessors.LIMIT
.processBefore(ProvidedQueryPostProcessors.IMPORT)
.processBefore(ProvidedQueryPostProcessors.HINT)
.processBefore(ProvidedQueryPostProcessors.TRACE));
}
/**
* Creates a new {@link StringBasedGemfireRepositoryQuery} using the given {@link GemfireQueryMethod} and
* {@link GemfireTemplate}. The actual query {@link String} will be looked up from the query method.
*
* @param queryMethod must not be {@literal null}.
* @param template must not be {@literal null}.
*/
public StringBasedGemfireRepositoryQuery(GemfireQueryMethod queryMethod, GemfireTemplate template) {
this(queryMethod.getAnnotatedQuery(), queryMethod, template);
}
/**
* Creates a new {@link StringBasedGemfireRepositoryQuery} using the given query {@link String},
* {@link GemfireQueryMethod} and {@link GemfireTemplate}.
*
* @param query will fall back to the query annotated to the given {@link GemfireQueryMethod} if {@literal null}.
* @param queryMethod must not be {@literal null}.
* @param template must not be {@literal null}.
*/
public StringBasedGemfireRepositoryQuery(String query, GemfireQueryMethod queryMethod, GemfireTemplate template) {
super(queryMethod);
Assert.notNull(template, "GemfireTemplate must not be null");
Assert.state(!(queryMethod.isModifyingQuery() || queryMethod.isPageQuery()), INVALID_QUERY);
this.userDefinedQuery |= !StringUtils.hasText(query);
this.query = QueryString.of(StringUtils.hasText(query) ? query : queryMethod.getAnnotatedQuery());
this.template = template;
register(ProvidedQueryPostProcessors.LIMIT
.processBefore(ProvidedQueryPostProcessors.IMPORT)
.processBefore(ProvidedQueryPostProcessors.HINT)
.processBefore(ProvidedQueryPostProcessors.TRACE));
}
/**
* Sets this {@link RepositoryQuery} to be user-defined.
*
* @return this {@link RepositoryQuery}.
*/
public StringBasedGemfireRepositoryQuery asUserDefinedQuery() {
this.userDefinedQuery = true;
return this;
}
/**
* Determines whether the query represented by this {@link RepositoryQuery} is user-defined or was generated by
* the Spring Data {@link Repository} infrastructure.
*
* @return a boolean value indicating whether this {@link RepositoryQuery} is user-defined or was generated by
* the Spring Data {@link Repository} infrastructure.
*/
public boolean isUserDefinedQuery() {
return this.userDefinedQuery;
}
/**
* Returns a reference to the {@link QueryString managed query}.
*
* @return a reference to the {@link QueryString managed query}.
* @see org.springframework.data.gemfire.repository.query.QueryString
*/
protected QueryString getQuery() {
return this.query;
}
/**
* Returns a reference to the {@link GemfireTemplate} used to perform all data access and query operations.
*
* @return a reference to the {@link GemfireTemplate} used to perform all data access and query operations.
* @see org.springframework.data.gemfire.GemfireTemplate
*/
protected GemfireTemplate getTemplate() {
return this.template;
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.RepositoryQuery#execute(java.lang.Object[])
*/
@Override
public Object execute(Object[] arguments) {
QueryMethod queryMethod = getQueryMethod();
QueryString query = preProcess(queryMethod, getQuery(), arguments);
String queryString = query.toString();
String processedQueryString = getQueryPostProcessor().postProcess(queryMethod, queryString, arguments);
SelectResults selectResults = getTemplate().find(processedQueryString, arguments);
return postProcess(queryMethod, selectResults);
}
QueryString preProcess(QueryMethod queryMethod, QueryString query, Object[] arguments) {
query = isUserDefinedQuery() ? query
: query.fromRegion(queryMethod.getEntityInformation().getJavaType(), getTemplate().getRegion());
ParametersParameterAccessor parameterAccessor =
new ParametersParameterAccessor(queryMethod.getParameters(), arguments);
for (Integer index : query.getInParameterIndexes()) {
query = query.bindIn(toCollection(parameterAccessor.getBindableValue(index - 1)));
}
return query;
}
Object postProcess(QueryMethod queryMethod, SelectResults selectResults) {
Collection collection = toCollection(selectResults);
if (queryMethod.isCollectionQuery()) {
return collection;
}
else if (queryMethod.isQueryForEntity()) {
if (collection.isEmpty()) {
return null;
}
else if (collection.size() == 1) {
return collection.iterator().next();
}
else {
throw new IncorrectResultSizeDataAccessException(1, collection.size());
}
}
else if (isSingleNonEntityResult(queryMethod, collection)) {
return collection.iterator().next();
}
else {
throw newIllegalStateException("Unsupported query: %s", query.toString());
}
}
@SuppressWarnings("all")
boolean isSingleNonEntityResult(QueryMethod method, Collection result) {
Class methodReturnType = method.getReturnedObjectType();
methodReturnType = methodReturnType != null ? methodReturnType : Void.class;
return nullSafeSize(result) == 1 && !Void.TYPE.equals(methodReturnType) && !method.isCollectionQuery();
}
/**
* Returns the given object as a Collection. Collections will be returned as is, Arrays will be converted into a
* Collection and all other objects will be wrapped into a single-element Collection.
*
* @param source the resulting object from the Pivotal GemFire Query.
* @return the querying resulting object as a Collection.
* @see java.util.Arrays#asList(Object[])
* @see java.util.Collection
* @see org.springframework.util.CollectionUtils#arrayToList(Object)
* @see org.apache.geode.cache.query.SelectResults
*/
Collection toCollection(Object source) {
if (source instanceof SelectResults) {
return ((SelectResults) source).asList();
}
if (source instanceof Collection) {
return (Collection) source;
}
if (source == null) {
return Collections.emptyList();
}
return source.getClass().isArray() ? CollectionUtils.arrayToList(source) : Collections.singletonList(source);
}
enum ProvidedQueryPostProcessors implements QueryPostProcessor {
HINT {
@Override
public String postProcess(QueryMethod queryMethod, String query, Object... arguments) {
if (queryMethod instanceof GemfireQueryMethod) {
GemfireQueryMethod gemfireQueryMethod = (GemfireQueryMethod) queryMethod;
if (gemfireQueryMethod.hasHint() && !QueryString.HINT_PATTERN.matcher(query).find()) {
query = QueryString.of(query).withHints(gemfireQueryMethod.getHints()).toString();
}
}
return query;
}
},
IMPORT {
@Override
public String postProcess(QueryMethod queryMethod, String query, Object... arguments) {
if (queryMethod instanceof GemfireQueryMethod) {
GemfireQueryMethod gemfireQueryMethod = (GemfireQueryMethod) queryMethod;
if (gemfireQueryMethod.hasImport() && !QueryString.IMPORT_PATTERN.matcher(query).find()) {
query = QueryString.of(query).withImport(gemfireQueryMethod.getImport()).toString();
}
}
return query;
}
},
LIMIT {
@Override
public String postProcess(QueryMethod queryMethod, String query, Object... arguments) {
if (queryMethod instanceof GemfireQueryMethod) {
GemfireQueryMethod gemfireQueryMethod = (GemfireQueryMethod) queryMethod;
if (gemfireQueryMethod.hasLimit() && !QueryString.LIMIT_PATTERN.matcher(query).find()) {
query = QueryString.of(query).withLimit(gemfireQueryMethod.getLimit()).toString();
}
}
return query;
}
},
TRACE {
@Override
public String postProcess(QueryMethod queryMethod, String query, Object... arguments) {
if (queryMethod instanceof GemfireQueryMethod) {
GemfireQueryMethod gemfireQueryMethod = (GemfireQueryMethod) queryMethod;
if (gemfireQueryMethod.hasTrace() && !QueryString.TRACE_PATTERN.matcher(query).find()) {
query = QueryString.of(query).withTrace().toString();
}
}
return query;
}
}
}
}