@Override
public ByteBuffer retrieveNextMessage(Connection c) throws IOException {
final NIOReadStream inputStream = c.readStream();
/*
* Note that access to the read stream is not synchronized. In this application
* the VoltPort will invoke this input handler to interact with the read stream guaranteeing
* thread safety. That said the Connection interface does allow other parts of the application
* access to the read stream.
*/
ByteBuffer result = null;
if (m_nextLength == 0 && inputStream.dataAvailable() > (Integer.SIZE / 8)) {
m_nextLength = inputStream.getInt();
if (m_nextLength < 1) {
throw new IOException(
"Next message length is " + m_nextLength + " which is less than 1 and is nonsense");
}
if (m_nextLength > 52428800) {
throw new IOException(
"Next message length is "
+ m_nextLength
+ " which is greater then the hard coded "
+ "max of 52428800. Break up the work into smaller chunks (2 megabytes is reasonable) "
+ "and send as multiple messages or stored procedure invocations");
}
assert m_nextLength > 0;
}
if (m_nextLength > 0 && inputStream.dataAvailable() >= m_nextLength) {
result = ByteBuffer.allocate(m_nextLength);
inputStream.getBytes(result.array());
m_nextLength = 0;
m_sequenceId++;
}
return result;
}
