// Reads a single packet from the connection, adding it to the packet
// queue when a complete packet is ready.
private void _readOnePacket() throws IOException {
byte[] data = null;
// Read in the packet
int length = _inStream.readInt();
if (length < 11) {
throw new IOException("JDWP packet length < 11 (" + length + ")");
}
data = new byte[length];
data[0] = (byte) (length >>> 24);
data[1] = (byte) (length >>> 16);
data[2] = (byte) (length >>> 8);
data[3] = (byte) length;
_inStream.readFully(data, 4, length - 4);
JdwpPacket packet = JdwpPacket.fromBytes(data);
if (packet != null) {
synchronized (_commandQueue) {
_commandQueue.add(packet);
_commandQueue.notifyAll();
}
}
}
/**
* Send an event notification to the debugger
*
* @param request the debugger request that wanted this event
* @param event the event
* @throws IOException
*/
public void sendEvent(EventRequest request, Event event) throws IOException {
JdwpPacket pkt;
synchronized (_bytes) {
_bytes.reset();
pkt = event.toPacket(_doStream, request);
pkt.setData(_bytes.toByteArray());
}
sendPacket(pkt);
}
/**
* Convert the given bytes into a <code>JdwpPacket</code>. Uses the abstract method <code>
* myFromBytes</code> to allow subclasses to process data.
*
* <p>If the given data does not represent a valid JDWP packet, it returns <code>null</code>.
*
* @param bytes packet data from the wire
* @return number of bytes in <code>bytes</code> processed
*/
public static JdwpPacket fromBytes(byte[] bytes) {
int i = 0;
int length =
((bytes[i++] & 0xff) << 24
| (bytes[i++] & 0xff) << 16
| (bytes[i++] & 0xff) << 8
| (bytes[i++] & 0xff));
int id = 0;
byte flags = 0;
if (bytes.length == length) {
id =
((bytes[i++] & 0xff) << 24
| (bytes[i++] & 0xff) << 16
| (bytes[i++] & 0xff) << 8
| (bytes[i++] & 0xff));
flags = bytes[i++];
Class clazz = null;
if (flags == 0) clazz = JdwpCommandPacket.class;
else if ((flags & JDWP_FLAG_REPLY) != 0) clazz = JdwpReplyPacket.class;
else {
// Malformed packet. Discard it.
return null;
}
JdwpPacket pkt = null;
try {
pkt = (JdwpPacket) clazz.newInstance();
} catch (InstantiationException ie) {
// Discard packet
return null;
} catch (IllegalAccessException iae) {
// Discard packet
return null;
}
pkt.setId(id);
pkt.setFlags(flags);
i += pkt.myFromBytes(bytes, i);
byte[] data = new byte[length - i];
System.arraycopy(bytes, i, data, 0, data.length);
pkt.setData(data);
return pkt;
}
return null;
}
/**
* Constructs a <code>JdwpPacket</code> with the id from the given packet.
*
* @param pkt a packet whose id will be used in this new packet
*/
public JdwpPacket(JdwpPacket pkt) {
_id = pkt.getId();
}
/**
* Send a packet to the debugger
*
* @param pkt a <code>JdwpPacket</code> to send
* @throws IOException
*/
public void sendPacket(JdwpPacket pkt) throws IOException {
pkt.write(_outStream);
}
