| /** |
| * 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.activemq.kaha.impl.index; |
| |
| import java.io.IOException; |
| import java.io.RandomAccessFile; |
| |
| import org.apache.activemq.util.DataByteArrayInputStream; |
| |
| /** |
| * Optimized Store reader |
| * |
| * |
| */ |
| class StoreIndexReader { |
| protected RandomAccessFile file; |
| protected DataByteArrayInputStream dataIn; |
| protected byte[] buffer = new byte[IndexItem.INDEX_SIZE]; |
| |
| /** |
| * Construct a Store reader |
| * |
| * @param file |
| */ |
| StoreIndexReader(RandomAccessFile file) { |
| this.file = file; |
| this.dataIn = new DataByteArrayInputStream(); |
| } |
| |
| protected IndexItem readItem(long offset) throws IOException { |
| file.seek(offset); |
| file.readFully(buffer); |
| dataIn.restart(buffer); |
| IndexItem result = new IndexItem(); |
| result.setOffset(offset); |
| result.read(dataIn); |
| return result; |
| } |
| |
| void updateIndexes(IndexItem indexItem) throws IOException { |
| if (indexItem != null) { |
| file.seek(indexItem.getOffset()); |
| file.readFully(buffer, 0, IndexItem.INDEXES_ONLY_SIZE); |
| dataIn.restart(buffer); |
| indexItem.readIndexes(dataIn); |
| } |
| } |
| } |