Package org.acplt.oncrpc
Class XdrUdpDecodingStream
java.lang.Object
org.acplt.oncrpc.XdrDecodingStream
org.acplt.oncrpc.XdrUdpDecodingStream
The
XdrUdpDecodingStream
class provides the necessary
functionality to XdrDecodingStream
to receive XDR packets from the
network using the datagram-oriented UDP/IP.- Version:
- $Revision: 1.2 $ $Date: 2005/11/11 21:07:40 $ $State: Exp $ $Locker: $
- Author:
- Harald Albrecht
-
Field Summary
FieldsModifier and TypeFieldDescriptionprivate byte[]
The buffer which will be filled from the datagram socket and then be used to supply the information when decoding data.private int
Index of the last four byte word in the buffer, which has been read in from the datagram socket.private int
The read pointer is an index into thebuffer
.private InetAddress
Sender's address of current buffer contents.private int
The senders's port.private DatagramSocket
The datagram socket to be used when receiving this XDR stream's buffer contents. -
Constructor Summary
ConstructorsConstructorDescriptionXdrUdpDecodingStream
(DatagramSocket datagramSocket, int bufferSize) Construct a newXdrUdpDecodingStream
object and associate it with the givendatagramSocket
for UDP/IP-based communication. -
Method Summary
Modifier and TypeMethodDescriptionvoid
Initiates decoding of the next XDR record.void
close()
Closes this decoding XDR stream and releases any system resources associated with this stream.void
End decoding of the current XDR record.Returns the Internet address of the sender of the current XDR data.int
Returns the port number of the sender of the current XDR data.int
Decodes (aka "deserializes") a "XDR int" value received from a XDR stream.void
xdrDecodeOpaque
(byte[] opaque, int offset, int length) Decodes (aka "deserializes") a XDR opaque value, which is represented by a vector of byte values, and starts atoffset
with a length oflength
.byte[]
xdrDecodeOpaque
(int length) Decodes (aka "deserializes") an opaque value, which is nothing more than a series of octets (or 8 bits wide bytes).Methods inherited from class org.acplt.oncrpc.XdrDecodingStream
getCharacterEncoding, setCharacterEncoding, xdrDecodeBoolean, xdrDecodeBooleanFixedVector, xdrDecodeBooleanVector, xdrDecodeByte, xdrDecodeByteFixedVector, xdrDecodeByteVector, xdrDecodeDouble, xdrDecodeDoubleFixedVector, xdrDecodeDoubleVector, xdrDecodeDynamicOpaque, xdrDecodeFloat, xdrDecodeFloatFixedVector, xdrDecodeFloatVector, xdrDecodeIntFixedVector, xdrDecodeIntVector, xdrDecodeLong, xdrDecodeLongFixedVector, xdrDecodeLongVector, xdrDecodeOpaque, xdrDecodeShort, xdrDecodeShortFixedVector, xdrDecodeShortVector, xdrDecodeString, xdrDecodeStringFixedVector, xdrDecodeStringVector
-
Field Details
-
socket
The datagram socket to be used when receiving this XDR stream's buffer contents. -
senderAddress
Sender's address of current buffer contents. -
senderPort
private int senderPortThe senders's port. -
buffer
private byte[] bufferThe buffer which will be filled from the datagram socket and then be used to supply the information when decoding data. -
bufferIndex
private int bufferIndexThe read pointer is an index into thebuffer
. -
bufferHighmark
private int bufferHighmarkIndex of the last four byte word in the buffer, which has been read in from the datagram socket.
-
-
Constructor Details
-
XdrUdpDecodingStream
Construct a newXdrUdpDecodingStream
object and associate it with the givendatagramSocket
for UDP/IP-based communication. This constructor is typically used when communicating with servers over UDP/IP using a "connected" datagram socket.- Parameters:
datagramSocket
- Datagram socket from which XDR data is received.bufferSize
- Size of packet buffer for storing received XDR datagrams.
-
-
Method Details
-
getSenderAddress
Returns the Internet address of the sender of the current XDR data. This method should only be called afterbeginDecoding()
, otherwise it might return stale information.- Specified by:
getSenderAddress
in classXdrDecodingStream
- Returns:
- InetAddress of the sender of the current XDR data.
-
getSenderPort
public int getSenderPort()Returns the port number of the sender of the current XDR data. This method should only be called afterbeginDecoding()
, otherwise it might return stale information.- Specified by:
getSenderPort
in classXdrDecodingStream
- Returns:
- Port number of the sender of the current XDR data.
-
beginDecoding
Initiates decoding of the next XDR record. For UDP-based XDR decoding streams this reads in the next datagram from the network socket.- Specified by:
beginDecoding
in classXdrDecodingStream
- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-
endDecoding
End decoding of the current XDR record. The general contract ofendDecoding
is that calling it is an indication that the current record is no more interesting to the caller and any allocated data for this record can be freed.This method overrides
XdrDecodingStream.endDecoding()
. It does nothing more than resetting the buffer pointer (eeek! a pointer in Java!!!) back to the begin of an empty buffer, so attempts to decode data will fail until the buffer is filled again.- Overrides:
endDecoding
in classXdrDecodingStream
- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-
close
Closes this decoding XDR stream and releases any system resources associated with this stream. A closed XDR stream cannot perform decoding operations and cannot be reopened.This implementation frees the allocated buffer but does not close the associated datagram socket. It only throws away the reference to this socket.
- Overrides:
close
in classXdrDecodingStream
- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-
xdrDecodeInt
Decodes (aka "deserializes") a "XDR int" value received from a XDR stream. A XDR int is 32 bits wide -- the same width Java's "int" data type has.- Specified by:
xdrDecodeInt
in classXdrDecodingStream
- Returns:
- The decoded int value.
- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-
xdrDecodeOpaque
Decodes (aka "deserializes") an opaque value, which is nothing more than a series of octets (or 8 bits wide bytes). Because the length of the opaque value is given, we don't need to retrieve it from the XDR stream. This is different fromxdrDecodeOpaque(byte[], int, int)
where first the length of the opaque value is retrieved from the XDR stream.- Specified by:
xdrDecodeOpaque
in classXdrDecodingStream
- Parameters:
length
- Length of opaque data to decode.- Returns:
- Opaque data as a byte vector.
- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-
xdrDecodeOpaque
public void xdrDecodeOpaque(byte[] opaque, int offset, int length) throws OncRpcException, IOException Decodes (aka "deserializes") a XDR opaque value, which is represented by a vector of byte values, and starts atoffset
with a length oflength
. Only the opaque value is decoded, so the caller has to know how long the opaque value will be. The decoded data is always padded to be a multiple of four (because that's what the sender does).- Specified by:
xdrDecodeOpaque
in classXdrDecodingStream
- Parameters:
opaque
- Byte vector which will receive the decoded opaque value.offset
- Start offset in the byte vector.length
- the number of bytes to decode.- Throws:
OncRpcException
- if an ONC/RPC error occurs.IOException
- if an I/O error occurs.
-