com.hazelcast.query.impl.OrResultSet Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2018, Hazelcast, Inc. All Rights Reserved.
*
* 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 com.hazelcast.query.impl;
import java.util.AbstractSet;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import static com.hazelcast.util.SetUtil.createHashSet;
/**
* Or result set for Predicates.
*/
public class OrResultSet extends AbstractSet {
private static final int ENTRY_MULTIPLE = 4;
private static final int ENTRY_MIN_SIZE = 8;
private final List> indexedResults;
private Set entries;
public OrResultSet(List> indexedResults) {
this.indexedResults = indexedResults;
}
@Override
public boolean contains(Object o) {
for (Set otherIndexedResult : indexedResults) {
if (otherIndexedResult.contains(o)) {
return true;
}
}
return false;
}
@Override
public Iterator iterator() {
return getEntries().iterator();
}
@Override
public int size() {
return getEntries().size();
}
/**
* @return returns estimated size without allocating the full result set
*/
public int estimatedSize() {
if (entries == null) {
if (indexedResults.isEmpty()) {
return 0;
} else {
return indexedResults.get(0).size();
}
}
return entries.size();
}
private Set getEntries() {
if (entries == null) {
if (indexedResults.isEmpty()) {
entries = Collections.emptySet();
} else {
if (indexedResults.size() == 1) {
entries = new HashSet(indexedResults.get(0));
} else {
entries = createHashSet(Math.max(ENTRY_MIN_SIZE, indexedResults.size() * ENTRY_MULTIPLE));
for (Set result : indexedResults) {
entries.addAll(result);
}
}
}
}
return entries;
}
}