| /** |
| * 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.util; |
| |
| import java.io.Serializable; |
| import java.util.LinkedList; |
| |
| /** |
| * Holder for many bitArrays - used for message audit |
| * |
| * |
| */ |
| public class BitArrayBin implements Serializable { |
| |
| private static final long serialVersionUID = 1L; |
| private LinkedList<BitArray> list; |
| private int maxNumberOfArrays; |
| private int firstIndex = -1; |
| private long lastInOrderBit=-1; |
| |
| /** |
| * Create a BitArrayBin to a certain window size (number of messages to |
| * keep) |
| * |
| * @param windowSize |
| */ |
| public BitArrayBin(int windowSize) { |
| maxNumberOfArrays = ((windowSize + 1) / BitArray.LONG_SIZE) + 1; |
| maxNumberOfArrays = Math.max(maxNumberOfArrays, 1); |
| list = new LinkedList<BitArray>(); |
| for (int i = 0; i < maxNumberOfArrays; i++) { |
| list.add(null); |
| } |
| } |
| |
| /** |
| * Set a bit |
| * |
| * @param index |
| * @param value |
| * @return true if set |
| */ |
| public boolean setBit(long index, boolean value) { |
| boolean answer = false; |
| BitArray ba = getBitArray(index); |
| if (ba != null) { |
| int offset = getOffset(index); |
| if (offset >= 0) { |
| answer = ba.set(offset, value); |
| } |
| } |
| return answer; |
| } |
| |
| /** |
| * Test if in order |
| * @param index |
| * @return true if next message is in order |
| */ |
| public boolean isInOrder(long index) { |
| boolean result = false; |
| if (lastInOrderBit == -1) { |
| result = true; |
| } else { |
| result = lastInOrderBit + 1 == index; |
| } |
| lastInOrderBit = index; |
| return result; |
| |
| } |
| |
| /** |
| * Get the boolean value at the index |
| * |
| * @param index |
| * @return true/false |
| */ |
| public boolean getBit(long index) { |
| boolean answer = index >= firstIndex; |
| BitArray ba = getBitArray(index); |
| if (ba != null) { |
| int offset = getOffset(index); |
| if (offset >= 0) { |
| answer = ba.get(offset); |
| return answer; |
| } |
| } else { |
| // gone passed range for previous bins so assume set |
| answer = true; |
| } |
| return answer; |
| } |
| |
| /** |
| * Get the BitArray for the index |
| * |
| * @param index |
| * @return BitArray |
| */ |
| private BitArray getBitArray(long index) { |
| int bin = getBin(index); |
| BitArray answer = null; |
| if (bin >= 0) { |
| if (bin >= maxNumberOfArrays) { |
| int overShoot = bin - maxNumberOfArrays + 1; |
| while (overShoot > 0) { |
| list.removeFirst(); |
| firstIndex += BitArray.LONG_SIZE; |
| list.add(new BitArray()); |
| overShoot--; |
| } |
| |
| bin = maxNumberOfArrays - 1; |
| } |
| answer = list.get(bin); |
| if (answer == null) { |
| answer = new BitArray(); |
| list.set(bin, answer); |
| } |
| } |
| return answer; |
| } |
| |
| /** |
| * Get the index of the bin from the total index |
| * |
| * @param index |
| * @return the index of the bin |
| */ |
| private int getBin(long index) { |
| int answer = 0; |
| if (firstIndex < 0) { |
| firstIndex = (int) (index - (index % BitArray.LONG_SIZE)); |
| } else if (firstIndex >= 0) { |
| answer = (int)((index - firstIndex) / BitArray.LONG_SIZE); |
| } |
| return answer; |
| } |
| |
| /** |
| * Get the offset into a bin from the total index |
| * |
| * @param index |
| * @return the relative offset into a bin |
| */ |
| private int getOffset(long index) { |
| int answer = 0; |
| if (firstIndex >= 0) { |
| answer = (int)((index - firstIndex) - (BitArray.LONG_SIZE * getBin(index))); |
| } |
| return answer; |
| } |
| |
| public long getLastSetIndex() { |
| long result = -1; |
| |
| if (firstIndex >=0) { |
| result = firstIndex; |
| BitArray last = null; |
| for (int lastBitArrayIndex = maxNumberOfArrays -1; lastBitArrayIndex >= 0; lastBitArrayIndex--) { |
| last = list.get(lastBitArrayIndex); |
| if (last != null) { |
| result += last.length() -1; |
| result += lastBitArrayIndex * BitArray.LONG_SIZE; |
| break; |
| } |
| } |
| } |
| return result; |
| } |
| } |