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;
}
