| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more contributor license |
| * agreements. See the NOTICE file distributed with this work for additional information regarding |
| * copyright ownership. The ASF licenses this file to You 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.apache.geode.cache.query.internal; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Set; |
| |
| import org.apache.geode.CopyHelper; |
| import org.apache.geode.cache.query.SelectResults; |
| import org.apache.geode.cache.query.Struct; |
| import org.apache.geode.cache.query.internal.types.StructTypeImpl; |
| import org.apache.geode.cache.query.types.CollectionType; |
| import org.apache.geode.cache.query.types.ObjectType; |
| |
| /** |
| * Class that wraps any SelectResults and performs copy on read when iterating through the results |
| * This should only be used when the cache itself has set copy-on-read to true This will save space |
| * in that we do not need to copy all results until they are actually accessed through |
| * iterator.next(). This wrapper will only be used for queries executed locally PartitionedRegion |
| * queries that are executed on the local node will already have been copied and will be treated as |
| * remote queries, so will not use this class |
| * |
| * The downside is that we may actually make two copies of the data if the cached data is actually a |
| * serialized byte array. toSet, toList, toArray and toArray(Object[] a) will create new structures |
| * that will iterate through the results using a SelectResultsCopyOnReadIterator. The new structures |
| * will then have a copy of the values. |
| * |
| * @since GemFire 8.0 |
| */ |
| public class ResultsCollectionCopyOnReadWrapper implements SelectResults { |
| SelectResults results; |
| |
| public ResultsCollectionCopyOnReadWrapper(SelectResults results) { |
| this.results = results; |
| } |
| |
| @Override |
| public Iterator iterator() { |
| return new SelectResultsCopyOnReadIterator(results.iterator()); |
| } |
| |
| private class SelectResultsCopyOnReadIterator implements Iterator { |
| |
| Iterator iterator; |
| |
| SelectResultsCopyOnReadIterator(Iterator iterator) { |
| this.iterator = iterator; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return iterator.hasNext(); |
| } |
| |
| @Override |
| public Object next() { |
| Object object = iterator.next(); |
| if (object instanceof Struct) { |
| Struct struct = (Struct) object; |
| Object[] values = struct.getFieldValues(); |
| Object[] newValues = new Object[values.length]; |
| int length = values.length; |
| for (int i = 0; i < length; i++) { |
| newValues[i] = CopyHelper.copy(values[i]); |
| } |
| return new StructImpl((StructTypeImpl) struct.getStructType(), newValues); |
| } else { |
| return CopyHelper.copy(object); |
| } |
| } |
| |
| @Override |
| public void remove() { |
| iterator.remove(); |
| } |
| } |
| |
| |
| // All other methods are pass throughs and won't actually be used. |
| @Override |
| public boolean add(Object e) { |
| return results.add(e); |
| } |
| |
| |
| |
| @Override |
| public boolean addAll(Collection c) { |
| return results.addAll(c); |
| } |
| |
| |
| |
| @Override |
| public void clear() { |
| results.clear(); |
| } |
| |
| |
| |
| @Override |
| public boolean contains(Object o) { |
| return results.contains(o); |
| } |
| |
| |
| |
| @Override |
| public boolean containsAll(Collection c) { |
| return results.containsAll(c); |
| } |
| |
| |
| |
| @Override |
| public boolean isEmpty() { |
| return results.isEmpty(); |
| } |
| |
| @Override |
| public boolean remove(Object o) { |
| return results.remove(o); |
| } |
| |
| |
| |
| @Override |
| public boolean removeAll(Collection c) { |
| return results.removeAll(c); |
| } |
| |
| |
| |
| @Override |
| public boolean retainAll(Collection c) { |
| return results.retainAll(c); |
| } |
| |
| |
| |
| @Override |
| public int size() { |
| return results.size(); |
| } |
| |
| @Override |
| public Object[] toArray() { |
| ArrayList arrayList = new ArrayList(); |
| Iterator iter = this.iterator(); |
| while (iter.hasNext()) { |
| arrayList.add(iter.next()); |
| } |
| return arrayList.toArray(); |
| } |
| |
| @Override |
| public Object[] toArray(Object[] a) { |
| Iterator iter = this.iterator(); |
| int i = 0; |
| while (iter.hasNext()) { |
| a[i++] = iter.next(); |
| } |
| return a; |
| } |
| |
| |
| @Override |
| public boolean isModifiable() { |
| return results.isModifiable(); |
| } |
| |
| |
| |
| @Override |
| public int occurrences(Object element) { |
| return results.occurrences(element); |
| } |
| |
| |
| |
| @Override |
| public Set asSet() { |
| return new HashSet(this); |
| } |
| |
| |
| |
| @Override |
| public List asList() { |
| return new ArrayList(this); |
| } |
| |
| |
| |
| @Override |
| public CollectionType getCollectionType() { |
| return results.getCollectionType(); |
| } |
| |
| |
| |
| @Override |
| public void setElementType(ObjectType elementType) { |
| results.setElementType(elementType); |
| } |
| |
| } |