/*
* Copyright 2004-2010 the Seasar Foundation and the Others.
*
* 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.slim3.datastore;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.slim3.util.ConversionUtil;
import com.google.appengine.api.datastore.AsyncDatastoreService;
import com.google.appengine.api.datastore.Cursor;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.PreparedQuery;
import com.google.appengine.api.datastore.QueryResultIterator;
import com.google.appengine.api.datastore.QueryResultList;
import com.google.appengine.api.datastore.Text;
import com.google.appengine.api.datastore.Transaction;
import com.google.appengine.api.datastore.Query.FilterOperator;
/**
* A query class for select.
*
* @author higa
* @param <M>
* the model type
* @since 1.0.0
*
*/
public class ModelQuery<M> extends AbstractQuery<ModelQuery<M>> {
/**
* The meta data of model.
*/
protected ModelMeta<M> modelMeta;
/**
* The in-memory filter criteria.
*/
protected List<InMemoryFilterCriterion> inMemoryFilterCriteria =
new ArrayList<InMemoryFilterCriterion>();
/**
* The in-memory sort orders.
*/
protected List<InMemorySortCriterion> inMemorySortCriteria =
new ArrayList<InMemorySortCriterion>();
/**
* Constructor.
*
* @param ds
* the asynchronous datastore service
* @param modelMeta
* the meta data of model
* @throws NullPointerException
* if the ds parameter is null or if the modelMeta parameter is
* null
*/
public ModelQuery(AsyncDatastoreService ds, ModelMeta<M> modelMeta)
throws NullPointerException {
super(ds);
if (modelMeta == null) {
throw new NullPointerException("The modelMeta parameter is null.");
}
this.modelMeta = modelMeta;
setUpQuery(modelMeta.getKind());
}
/**
* Constructor.
*
* @param ds
* the asynchronous datastore service
* @param modelMeta
* the meta data of model
* @param ancestorKey
* the ancestor key
* @throws NullPointerException
* if the ds parameter is null or if the modelMeta parameter is
* null or if the ancestorKey parameter is null
*/
public ModelQuery(AsyncDatastoreService ds, ModelMeta<M> modelMeta,
Key ancestorKey) throws NullPointerException {
super(ds);
if (modelMeta == null) {
throw new NullPointerException("The modelMeta parameter is null.");
}
if (ancestorKey == null) {
throw new NullPointerException("The ancestorKey parameter is null.");
}
this.modelMeta = modelMeta;
setUpQuery(modelMeta.getKind(), ancestorKey);
}
/**
* Constructor.
*
* @param ds
* the asynchronous datastore service
* @param tx
* the transaction
* @param modelMeta
* the meta data of model
* @param ancestorKey
* the ancestor key
* @throws NullPointerException
* if the ds parameter is null or if the modelMeta parameter is
* null or if the ancestorKey parameter is null
*/
public ModelQuery(AsyncDatastoreService ds, Transaction tx,
ModelMeta<M> modelMeta, Key ancestorKey)
throws NullPointerException {
super(ds);
if (modelMeta == null) {
throw new NullPointerException("The modelMeta parameter is null.");
}
if (ancestorKey == null) {
throw new NullPointerException("The ancestorKey parameter is null.");
}
setTx(tx);
this.modelMeta = modelMeta;
setUpQuery(modelMeta.getKind(), ancestorKey);
}
/**
* Adds the filter criteria.
*
* @param criteria
* the filter criteria
* @return this instance
* @throws NullPointerException
* if the element of the criteria parameter is null
*/
public ModelQuery<M> filter(FilterCriterion... criteria)
throws NullPointerException {
for (FilterCriterion c : criteria) {
if (c == null) {
throw new NullPointerException(
"The element of the criteria parameter must not be null.");
}
for (Filter f : c.getFilters()) {
Object value = f.getValue();
if (modelMeta.isCipherProperty(f.getPropertyName())) {
if (value instanceof String) {
value = modelMeta.encrypt((String) value);
} else if (value instanceof Text) {
value = modelMeta.encrypt((Text) value);
}
}
query.addFilter(f.getPropertyName(), f.getOperator(), value);
}
}
return this;
}
/**
* Adds the in-memory filter criteria.
*
* @param criteria
* the in-memory filter criteria
* @return this instance
* @throws NullPointerException
* if the element of the criteria parameter is null
*/
public ModelQuery<M> filterInMemory(InMemoryFilterCriterion... criteria)
throws NullPointerException {
for (InMemoryFilterCriterion c : criteria) {
if (c == null) {
throw new NullPointerException(
"The element of the criteria parameter must not be null.");
}
inMemoryFilterCriteria.add(c);
}
return this;
}
/**
* Adds the sort criteria.
*
* @param criteria
* the sort criteria
* @return this instance
* @throws NullPointerException
* if the element of the criteria parameter is null
*/
public ModelQuery<M> sort(SortCriterion... criteria)
throws NullPointerException {
for (SortCriterion c : criteria) {
if (c == null) {
throw new NullPointerException(
"The element of the criteria parameter must not be null.");
}
Sort s = c.getSort();
query.addSort(s.getPropertyName(), s.getDirection());
}
return this;
}
/**
* Adds the in-memory sort criteria.
*
* @param criteria
* the in-memory sort criteria
* @return this instance
* @throws NullPointerException
* if the element of the criteria parameter is null
*/
public ModelQuery<M> sortInMemory(InMemorySortCriterion... criteria)
throws NullPointerException {
for (InMemorySortCriterion c : criteria) {
if (c == null) {
throw new NullPointerException(
"The element of the criteria parameter must not be null.");
}
inMemorySortCriteria.add(c);
}
return this;
}
/**
* Returns the result as a list.
*
* @return the result as a list
*/
public List<M> asList() {
addFilterIfPolyModel();
List<Entity> entityList = asEntityList();
List<M> ret = new ArrayList<M>(entityList.size());
for (Entity e : entityList) {
ModelMeta<M> mm = DatastoreUtil.getModelMeta(modelMeta, e);
ret.add(mm.entityToModel(e));
}
ret = DatastoreUtil.filterInMemory(ret, inMemoryFilterCriteria);
return DatastoreUtil.sortInMemory(ret, inMemorySortCriteria);
}
/**
* Returns a query result list.
*
* @return a query result list
*/
public S3QueryResultList<M> asQueryResultList() {
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asQueryResultList(), you cannot specify filterInMemory().");
}
if (inMemorySortCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asQueryResultList(), you cannot specify sortInMemory().");
}
addFilterIfPolyModel();
List<M> modelList = null;
boolean hasNext = false;
Cursor cursor = null;
if (fetchOptions.getLimit() == null) {
QueryResultList<Entity> entityList = asQueryResultEntityList();
modelList = new ArrayList<M>(entityList.size());
for (Entity e : entityList) {
ModelMeta<M> mm = DatastoreUtil.getModelMeta(modelMeta, e);
modelList.add(mm.entityToModel(e));
}
cursor = entityList.getCursor();
} else {
int limit = fetchOptions.getLimit();
fetchOptions.limit(limit + 1);
modelList = new ArrayList<M>();
QueryResultIterator<Entity> ite = asQueryResultEntityIterator();
while (true) {
hasNext = ite.hasNext();
if (!hasNext || modelList.size() == limit) {
cursor = ite.getCursor();
break;
}
Entity e = ite.next();
ModelMeta<M> mm = DatastoreUtil.getModelMeta(modelMeta, e);
modelList.add(mm.entityToModel(e));
}
}
return new S3QueryResultList<M>(
modelList,
cursor.toWebSafeString(),
getEncodedFilters(),
getEncodedSorts(),
hasNext);
}
/**
* Returns the single result or null if no entities match.
*
* @return the single result
* @throws PreparedQuery.TooManyResultsException
* if the number of the results are more than 1 entity.
*
*/
public M asSingle() throws PreparedQuery.TooManyResultsException {
List<M> list = asList();
if (list.size() == 0) {
return null;
}
if (list.size() > 1) {
throw new PreparedQuery.TooManyResultsException();
}
return list.get(0);
}
/**
* Returns a list of keys.
*
* @return a list of keys
* @throws IllegalStateException
* if in-memory filers are specified
*/
@Override
public List<Key> asKeyList() throws IllegalStateException {
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In the case of asKeyList(), you cannot specify filterInMemory().");
}
addFilterIfPolyModel();
List<Key> keys = super.asKeyList();
if (inMemorySortCriteria.size() > 0 && inMemorySortCriteria.size() == 1) {
InMemorySortCriterion c = inMemorySortCriteria.get(0);
if (c instanceof AbstractCriterion) {
if (((AbstractCriterion) c).attributeMeta.name
.equals(Entity.KEY_RESERVED_PROPERTY)) {
if (c instanceof AscCriterion) {
Collections.sort(keys);
} else {
Collections.sort(keys, KeyDescComparator.INSTANCE);
}
return keys;
}
}
throw new IllegalStateException(
"In the case of asKeyList(), you cannot specify sortInMemory() except for primary key.");
}
return keys;
}
/**
* Returns the result as an {@link Iterator}.
*
* @return the result as an {@link Iterator}
* @throws IllegalStateException
* if in-memory filers are specified or if in-memory sorts are
* specified
*/
public Iterator<M> asIterator() throws IllegalStateException {
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asIterator(), you cannot specify filterInMemory().");
}
if (inMemorySortCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asIterator(), you cannot specify sortInMemory().");
}
addFilterIfPolyModel();
Iterator<Entity> entityIterator = asEntityIterator();
return new ModelIterator<M>(entityIterator, modelMeta);
}
/**
* Returns the result as an {@link Iterable}.
*
* @return the result as an {@link Iterable}
* @throws IllegalStateException
* if in-memory filers are specified or if in-memory sorts are
* specified
*/
public Iterable<M> asIterable() throws IllegalStateException {
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asIterable(), you cannot specify filterInMemory().");
}
if (inMemorySortCriteria.size() > 0) {
throw new IllegalStateException(
"In case of asIterable(), you cannot specify sortInMemory().");
}
return new ModelIterable<M>(asIterator());
}
/**
* Return a minimum value of the property. The value does not include null.
*
* @param <A>
* the attribute type
* @param attributeMeta
* the meta data of attribute
* @return a minimum value of the property
* @throws NullPointerException
* if the attributeMeta parameter is null
* @throws IllegalStateException
* if in-memory filers are specified or if in-memory sorts are
* specified
*/
@SuppressWarnings("unchecked")
public <A> A min(CoreAttributeMeta<M, A> attributeMeta)
throws NullPointerException, IllegalStateException {
if (attributeMeta == null) {
throw new NullPointerException(
"The attributeMeta parameter is null.");
}
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In case of min(), you cannot specify filterInMemory().");
}
if (inMemorySortCriteria.size() > 0) {
throw new IllegalStateException(
"In case of min(), you cannot specify sortInMemory().");
}
addFilterIfPolyModel();
Object value = super.min(attributeMeta.getName());
return (A) ConversionUtil.convert(value, attributeMeta
.getAttributeClass());
}
/**
* Return a maximum value of the property.
*
* @param <A>
* the attribute type
* @param attributeMeta
* the meta data of attribute
* @return a maximum value of the property
* @throws NullPointerException
* if the attributeMeta parameter is null
* @throws IllegalStateException
* if in-memory filters are specified or if in-memory sorts are
* specified
*/
@SuppressWarnings("unchecked")
public <A> A max(CoreAttributeMeta<M, A> attributeMeta)
throws NullPointerException, IllegalStateException {
if (attributeMeta == null) {
throw new NullPointerException(
"The attributeMeta parameter is null.");
}
if (inMemoryFilterCriteria.size() > 0) {
throw new IllegalStateException(
"In case of max(), you cannot specify filterInMemory().");
}
if (inMemorySortCriteria.size() > 0) {
throw new IllegalStateException(
"In case of max(), you cannot specify sortInMemory().");
}
addFilterIfPolyModel();
Object value = super.max(attributeMeta.getName());
return (A) ConversionUtil.convert(value, attributeMeta
.getAttributeClass());
}
/**
* Returns a number of entities.
*
* @return a number of entities
*/
@Override
public int count() {
inMemorySortCriteria.clear();
addFilterIfPolyModel();
if (inMemoryFilterCriteria.size() > 0) {
return asList().size();
}
return super.count();
}
/**
* Adds a filter for polymorphic model.
*/
protected void addFilterIfPolyModel() {
if (modelMeta.getClassHierarchyList().isEmpty()) {
return;
}
query.addFilter(
modelMeta.getClassHierarchyListName(),
FilterOperator.EQUAL,
modelMeta.getModelClass().getName());
}
}