/*
* Copyright 2012 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.gemfire.repository.query;
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.query.ParametersParameterAccessor;
import org.springframework.data.repository.query.QueryMethod;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;
/**
* {@link GemfireRepositoryQuery} using plain {@link String} based OQL queries.
* <p>
* @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() {
query = null;
template = null;
}
/**
* 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");
this.userDefinedQuery |= !StringUtils.hasText(query);
this.query = new QueryString(StringUtils.hasText(query) ? query : queryMethod.getAnnotatedQuery());
this.template = template;
if (queryMethod.isModifyingQuery() || queryMethod.isPageQuery()) {
throw new IllegalStateException(INVALID_QUERY);
}
}
/*
* (non-Javadoc)
*/
public StringBasedGemfireRepositoryQuery asUserDefinedQuery() {
this.userDefinedQuery = true;
return this;
}
/*
* (non-Javadoc)
*/
public boolean isUserDefinedQuery() {
return userDefinedQuery;
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.RepositoryQuery#execute(java.lang.Object[])
*/
@Override
public Object execute(Object[] parameters) {
QueryMethod localQueryMethod = getQueryMethod();
QueryString query = (isUserDefinedQuery() ? this.query
: this.query.forRegion(localQueryMethod.getEntityInformation().getJavaType(), template.getRegion()));
ParametersParameterAccessor parameterAccessor =
new ParametersParameterAccessor(localQueryMethod.getParameters(), parameters);
for (Integer index : query.getInParameterIndexes()) {
query = query.bindIn(toCollection(parameterAccessor.getBindableValue(index - 1)));
}
query = applyQueryAnnotationExtensions(localQueryMethod, query);
Collection<?> result = toCollection(template.find(query.toString(), parameters));
if (localQueryMethod.isCollectionQuery()) {
return result;
}
else if (localQueryMethod.isQueryForEntity()) {
if (result.isEmpty()) {
return null;
}
else if (result.size() == 1) {
return result.iterator().next();
}
else {
throw new IncorrectResultSizeDataAccessException(1, result.size());
}
}
else if (isSingleResultNonEntityQuery(localQueryMethod, result)) {
return result.iterator().next();
}
else {
throw new IllegalStateException("Unsupported query: " + query.toString());
}
}
QueryString applyQueryAnnotationExtensions(QueryMethod queryMethod, QueryString queryString) {
QueryString resolvedQueryString = queryString;
if (queryMethod instanceof GemfireQueryMethod) {
GemfireQueryMethod gemfireQueryMethod = (GemfireQueryMethod) queryMethod;
String query = queryString.toString().toUpperCase();
if (gemfireQueryMethod.hasImport() && !QueryString.IMPORT_PATTERN.matcher(query).find()) {
resolvedQueryString = resolvedQueryString.withImport(gemfireQueryMethod.getImport());
}
if (gemfireQueryMethod.hasHint() && !QueryString.HINT_PATTERN.matcher(query).find()) {
resolvedQueryString = resolvedQueryString.withHints(gemfireQueryMethod.getHints());
}
if (gemfireQueryMethod.hasLimit() && !QueryString.LIMIT_PATTERN.matcher(query).find()) {
resolvedQueryString = resolvedQueryString.withLimit(gemfireQueryMethod.getLimit());
}
if (gemfireQueryMethod.hasTrace() && !QueryString.TRACE_PATTERN.matcher(query).find()) {
resolvedQueryString = resolvedQueryString.withTrace();
}
}
return resolvedQueryString;
}
boolean isSingleResultNonEntityQuery(QueryMethod method, Collection<?> result) {
return (!method.isCollectionQuery() && method.getReturnedObjectType() != null
&& !Void.TYPE.equals(method.getReturnedObjectType()) && result != null && result.size() == 1);
}
/**
* 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 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(final 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));
}
}