public synchronized List<PagedMessage> read(StorageManager storage) throws Exception { if (isDebug) { HornetQServerLogger.LOGGER.debug( "reading page " + this.pageId + " on address = " + storeName); } if (!file.isOpen()) { throw HornetQMessageBundle.BUNDLE.invalidPageIO(); } ArrayList<PagedMessage> messages = new ArrayList<PagedMessage>(); size.set((int) file.size()); // Using direct buffer, as described on https://jira.jboss.org/browse/HORNETQ-467 ByteBuffer directBuffer = storage.allocateDirectBuffer((int) file.size()); try { file.position(0); file.read(directBuffer); directBuffer.rewind(); HornetQBuffer fileBuffer = HornetQBuffers.wrappedBuffer(directBuffer); fileBuffer.writerIndex(fileBuffer.capacity()); while (fileBuffer.readable()) { final int position = fileBuffer.readerIndex(); byte byteRead = fileBuffer.readByte(); if (byteRead == Page.START_BYTE) { if (fileBuffer.readerIndex() + DataConstants.SIZE_INT < fileBuffer.capacity()) { int messageSize = fileBuffer.readInt(); int oldPos = fileBuffer.readerIndex(); if (fileBuffer.readerIndex() + messageSize < fileBuffer.capacity() && fileBuffer.getByte(oldPos + messageSize) == Page.END_BYTE) { PagedMessage msg = new PagedMessageImpl(); msg.decode(fileBuffer); byte b = fileBuffer.readByte(); if (b != Page.END_BYTE) { // Sanity Check: This would only happen if there is a bug on decode or any internal // code, as // this // constraint was already checked throw new IllegalStateException( "Internal error, it wasn't possible to locate END_BYTE " + b); } msg.initMessage(storage); if (isTrace) { HornetQServerLogger.LOGGER.trace( "Reading message " + msg + " on pageId=" + this.pageId + " for address=" + storeName); } messages.add(msg); } else { markFileAsSuspect(file.getFileName(), position, messages.size()); break; } } } else { markFileAsSuspect(file.getFileName(), position, messages.size()); break; } } } finally { storage.freeDirectBuffer(directBuffer); } numberOfMessages.set(messages.size()); return messages; }