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java.net
public final class: DatagramPacket [javadoc | source]
java.lang.Object
   java.net.DatagramPacket
This class represents a datagram packet.

Datagram packets are used to implement a connectionless packet delivery service. Each message is routed from one machine to another based solely on information contained within that packet. Multiple packets sent from one machine to another might be routed differently, and might arrive in any order. Packet delivery is not guaranteed.

Field Summary
 byte[] buf    Perform class initialization 
 int offset     
 int length     
 int bufLength     
 InetAddress address     
 int port     
Constructor:
 public DatagramPacket(byte[] buf,
    int length) 
 public DatagramPacket(byte[] buf,
    int offset,
    int length) 
 public DatagramPacket(byte[] buf,
    int length,
    SocketAddress address) throws SocketException 
    Constructs a datagram packet for sending packets of length length to the specified port number on the specified host. The length argument must be less than or equal to buf.length.
    Parameters:
    buf - the packet data.
    length - the packet length.
    address - the destination address.
    Throws:
    IllegalArgumentException - if address type is not supported
    Also see:
    java.net.InetAddress
    since: 1.4 -
 public DatagramPacket(byte[] buf,
    int offset,
    int length,
    SocketAddress address) throws SocketException 
    Constructs a datagram packet for sending packets of length length with offset ioffsetto the specified port number on the specified host. The length argument must be less than or equal to buf.length.
    Parameters:
    buf - the packet data.
    offset - the packet data offset.
    length - the packet data length.
    address - the destination socket address.
    Throws:
    IllegalArgumentException - if address type is not supported
    Also see:
    java.net.InetAddress
    since: 1.4 -
 public DatagramPacket(byte[] buf,
    int length,
    InetAddress address,
    int port) 
    Constructs a datagram packet for sending packets of length length to the specified port number on the specified host. The length argument must be less than or equal to buf.length.
    Parameters:
    buf - the packet data.
    length - the packet length.
    address - the destination address.
    port - the destination port number.
    Also see:
    java.net.InetAddress
 public DatagramPacket(byte[] buf,
    int offset,
    int length,
    InetAddress address,
    int port) 
    Constructs a datagram packet for sending packets of length length with offset ioffsetto the specified port number on the specified host. The length argument must be less than or equal to buf.length.
    Parameters:
    buf - the packet data.
    offset - the packet data offset.
    length - the packet data length.
    address - the destination address.
    port - the destination port number.
    Also see:
    java.net.InetAddress
    since: 1.2 -
Method from java.net.DatagramPacket Summary:
getAddress,   getData,   getLength,   getOffset,   getPort,   getSocketAddress,   setAddress,   setData,   setData,   setLength,   setPort,   setSocketAddress
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.net.DatagramPacket Detail:
 public synchronized InetAddress getAddress() 
    Returns the IP address of the machine to which this datagram is being sent or from which the datagram was received.
 public synchronized byte[] getData() 
    Returns the data buffer. The data received or the data to be sent starts from the offset in the buffer, and runs for length long.
 public synchronized int getLength() 
    Returns the length of the data to be sent or the length of the data received.
 public synchronized int getOffset() 
    Returns the offset of the data to be sent or the offset of the data received.
 public synchronized int getPort() 
    Returns the port number on the remote host to which this datagram is being sent or from which the datagram was received.
 public synchronized SocketAddress getSocketAddress() 
    Gets the SocketAddress (usually IP address + port number) of the remote host that this packet is being sent to or is coming from.
 public synchronized  void setAddress(InetAddress iaddr) 
    Sets the IP address of the machine to which this datagram is being sent.
 public synchronized  void setData(byte[] buf) 
    Set the data buffer for this packet. With the offset of this DatagramPacket set to 0, and the length set to the length of buf.
 public synchronized  void setData(byte[] buf,
    int offset,
    int length) 
    Set the data buffer for this packet. This sets the data, length and offset of the packet.
 public synchronized  void setLength(int length) 
    Set the length for this packet. The length of the packet is the number of bytes from the packet's data buffer that will be sent, or the number of bytes of the packet's data buffer that will be used for receiving data. The length must be lesser or equal to the offset plus the length of the packet's buffer.
 public synchronized  void setPort(int iport) 
    Sets the port number on the remote host to which this datagram is being sent.
 public synchronized  void setSocketAddress(SocketAddress address) 
    Sets the SocketAddress (usually IP address + port number) of the remote host to which this datagram is being sent.