| /* |
| * 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.accumulo.iteratortest; |
| |
| import java.io.IOException; |
| import java.util.Collection; |
| import java.util.Map; |
| |
| import org.apache.accumulo.core.data.ByteSequence; |
| import org.apache.accumulo.core.data.Key; |
| import org.apache.accumulo.core.data.Range; |
| import org.apache.accumulo.core.data.Value; |
| import org.apache.accumulo.core.iterators.IteratorEnvironment; |
| import org.apache.accumulo.core.iterators.SortedKeyValueIterator; |
| |
| /** |
| * Internally, Accumulo reuses the same instance of Key and Value to reduce the number of objects to |
| * be garbage collected. This iterator simulates that. |
| */ |
| public class SimpleKVReusingIterator implements SortedKeyValueIterator<Key,Value> { |
| |
| private final SortedKeyValueIterator<Key,Value> source; |
| private final Key topKey = new Key(); |
| private final Value topValue = new Value(); |
| |
| public SimpleKVReusingIterator(SortedKeyValueIterator<Key,Value> source) { |
| this.source = source; |
| } |
| |
| @Override |
| public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, |
| IteratorEnvironment env) throws IOException { |
| this.source.init(source, options, env); |
| } |
| |
| @Override |
| public boolean hasTop() { |
| return source.hasTop(); |
| } |
| |
| @Override |
| public void next() throws IOException { |
| source.next(); |
| load(); |
| } |
| |
| @Override |
| public void seek(Range range, Collection<ByteSequence> columnFamilies, boolean inclusive) |
| throws IOException { |
| source.seek(range, columnFamilies, inclusive); |
| load(); |
| } |
| |
| @Override |
| public Key getTopKey() { |
| return topKey; |
| } |
| |
| @Override |
| public Value getTopValue() { |
| return topValue; |
| } |
| |
| @Override |
| public SortedKeyValueIterator<Key,Value> deepCopy(IteratorEnvironment env) { |
| SortedKeyValueIterator<Key,Value> newSource = source.deepCopy(env); |
| return new SimpleKVReusingIterator(newSource); |
| } |
| |
| private void load() { |
| if (hasTop()) { |
| topKey.set(source.getTopKey()); |
| topValue.set(source.getTopValue().get()); |
| } |
| } |
| } |