datagramsocket.html

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          Sets the datagram socket implementation factory for the
 application.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/net/DatagramSocket.html#setReceiveBufferSize(int)">setReceiveBufferSize</A></B>(int&nbsp;size)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sets the SO_RCVBUF option to the specified value for this
 <tt>DatagramSocket</tt>.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/net/DatagramSocket.html#setSendBufferSize(int)">setSendBufferSize</A></B>(int&nbsp;size)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sets the SO_SNDBUF option to the specified value for this
 <tt>DatagramSocket</tt>.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/net/DatagramSocket.html#setSoTimeout(int)">setSoTimeout</A></B>(int&nbsp;timeout)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Enable/disable SO_TIMEOUT with the specified timeout, in
  milliseconds.</TD>
</TR>
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<TD><B>Methods inherited from class java.lang.<A HREF="../../java/lang/Object.html">Object</A></B></TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../java/lang/Object.html#clone()">clone</A>, <A HREF="../../java/lang/Object.html#equals(java.lang.Object)">equals</A>, <A HREF="../../java/lang/Object.html#finalize()">finalize</A>, <A HREF="../../java/lang/Object.html#getClass()">getClass</A>, <A HREF="../../java/lang/Object.html#hashCode()">hashCode</A>, <A HREF="../../java/lang/Object.html#notify()">notify</A>, <A HREF="../../java/lang/Object.html#notifyAll()">notifyAll</A>, <A HREF="../../java/lang/Object.html#toString()">toString</A>, <A HREF="../../java/lang/Object.html#wait()">wait</A>, <A HREF="../../java/lang/Object.html#wait(long)">wait</A>, <A HREF="../../java/lang/Object.html#wait(long, int)">wait</A></CODE></TD>
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<!-- ============ FIELD DETAIL =========== -->


<!-- ========= CONSTRUCTOR DETAIL ======== -->

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<B>Constructor Detail</B></FONT></TD>
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<A NAME="DatagramSocket()"><!-- --></A><H3>
DatagramSocket</H3>
<PRE>
public <B>DatagramSocket</B>()
               throws <A HREF="../../java/net/SocketException.html">SocketException</A></PRE>
<DL>
<DD>Constructs a datagram socket and binds it to any available port
 on the local host machine.
 
 <p>If there is a security manager, 
 its <code>checkListen</code> method is first called
 with 0 as its argument to ensure the operation is allowed. 
 This could result in a SecurityException.<DD><DL>
<DT><B>Throws:</B><DD><CODE><A HREF="../../java/net/SocketException.html">SocketException</A></CODE> - if the socket could not be opened,
               or the socket could not bind to the specified local port.<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkListen</code> method doesn't allow the operation.<DT><B>See Also: </B><DD><A HREF="../../java/lang/SecurityManager.html#checkListen(int)"><CODE>SecurityManager.checkListen(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="DatagramSocket(int)"><!-- --></A><H3>
DatagramSocket</H3>
<PRE>
public <B>DatagramSocket</B>(int&nbsp;port)
               throws <A HREF="../../java/net/SocketException.html">SocketException</A></PRE>
<DL>
<DD>Constructs a datagram socket and binds it to the specified port
 on the local host machine.
 
 <p>If there is a security manager, 
 its <code>checkListen</code> method is first called
 with the <code>port</code> argument
 as its argument to ensure the operation is allowed. 
 This could result in a SecurityException.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>port</CODE> - port to use.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/net/SocketException.html">SocketException</A></CODE> - if the socket could not be opened,
               or the socket could not bind to the specified local port.<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkListen</code> method doesn't allow the operation.<DT><B>See Also: </B><DD><A HREF="../../java/lang/SecurityManager.html#checkListen(int)"><CODE>SecurityManager.checkListen(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="DatagramSocket(int, java.net.InetAddress)"><!-- --></A><H3>
DatagramSocket</H3>
<PRE>
public <B>DatagramSocket</B>(int&nbsp;port,
                      <A HREF="../../java/net/InetAddress.html">InetAddress</A>&nbsp;laddr)
               throws <A HREF="../../java/net/SocketException.html">SocketException</A></PRE>
<DL>
<DD>Creates a datagram socket, bound to the specified local
 address.  The local port must be between 0 and 65535 inclusive.
 
 <p>If there is a security manager, 
 its <code>checkListen</code> method is first called
 with the <code>port</code> argument
 as its argument to ensure the operation is allowed. 
 This could result in a SecurityException.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>port</CODE> - local port to use<DD><CODE>laddr</CODE> - local address to bind<DT><B>Throws:</B><DD><CODE><A HREF="../../java/net/SocketException.html">SocketException</A></CODE> - if the socket could not be opened,
               or the socket could not bind to the specified local port.<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkListen</code> method doesn't allow the operation.<DT><B>Since: </B><DD>JDK1.1</DD>
<DT><B>See Also: </B><DD><A HREF="../../java/lang/SecurityManager.html#checkListen(int)"><CODE>SecurityManager.checkListen(int)</CODE></A></DL>
</DD>
</DL>

<!-- ============ METHOD DETAIL ========== -->

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<A NAME="connect(java.net.InetAddress, int)"><!-- --></A><H3>
connect</H3>
<PRE>
public void <B>connect</B>(<A HREF="../../java/net/InetAddress.html">InetAddress</A>&nbsp;address,
                    int&nbsp;port)</PRE>
<DL>
<DD>Connects the socket to a remote address for this socket. When a
 socket is connected to a remote address, packets may only be
 sent to or received from that address. By default a datagram
 socket is not connected.

 <p>A caller's permission to send and receive datagrams to a
 given host and port are checked at connect time. When a socket
 is connected, receive and send <b>will not
 perform any security checks</b> on incoming and outgoing
 packets, other than matching the packet's and the socket's
 address and port. On a send operation, if the packet's address
 is set and the packet's address and the socket's address do not
 match, an IllegalArgumentException will be thrown. A socket
 connected to a multicast address may only be used to send packets.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>address</CODE> - the remote address for the socket<DD><CODE>port</CODE> - the remote port for the socket.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/IllegalArgumentException.html">IllegalArgumentException</A></CODE> - if the address is invalid
 or the port is out of range.<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if the caller is not allowed to
 send datagrams to and receive datagrams from the address and port.<DT><B>See Also: </B><DD><A HREF="../../java/net/DatagramSocket.html#disconnect()"><CODE>disconnect()</CODE></A>, 
<A HREF="../../java/net/DatagramSocket.html#send(java.net.DatagramPacket)"><CODE>send(java.net.DatagramPacket)</CODE></A>, 
<A HREF="../../java/net/DatagramSocket.html#receive(java.net.DatagramPacket)"><CODE>receive(java.net.DatagramPacket)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="disconnect()"><!-- --></A><H3>
disconnect</H3>
<PRE>
public void <B>disconnect</B>()</PRE>
<DL>
<DD>Disconnects the socket. This does nothing if the socket is not
 connected.<DD><DL>
<DT><B>See Also: </B><DD><A HREF="../../java/net/DatagramSocket.html#connect(java.net.InetAddress, int)"><CODE>connect(java.net.InetAddress, int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="getInetAddress()"><!-- --></A><H3>
getInetAddress</H3>
<PRE>
public <A HREF="../../java/net/InetAddress.html">InetAddress</A> <B>getInetAddress</B>()</PRE>
<DL>
<DD>Returns the address to which this socket is connected. Returns null
 if the socket is not connected.<DD><DL>
<DT><B>Returns:</B><DD>the address to which this socket is connected.</DL>
</DD>
</DL>
<HR>

<A NAME="getPort()"><!-- --></A><H3>
getPort</H3>
<PRE>
public int <B>getPort</B>()</PRE>
<DL>
<DD>Returns the port for this socket. Returns -1 if the socket is not
 connected.<DD><DL>
<DT><B>Returns:</B><DD>the port to which this socket is connected.</DL>
</DD>
</DL>
<HR>

<A NAME="send(java.net.DatagramPacket)"><!-- --></A><H3>
send</H3>
<PRE>
public void <B>send</B>(<A HREF="../../java/net/DatagramPacket.html">DatagramPacket</A>&nbsp;p)
          throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Sends a datagram packet from this socket. The
 <code>DatagramPacket</code> includes information indicating the
 data to be sent, its length, the IP address of the remote host,
 and the port number on the remote host.

 <p>If there is a security manager, and the socket is not currently
 connected to a remote address, this method first performs some
 security checks. First, if <code>p.getAddress().isMulticastAddress()</code>
 is true, this method calls the
 security manager's <code>checkMulticast</code> method
 with <code>p.getAddress()</code> as its argument.
 If the evaluation of that expression is false,
 this method instead calls the security manager's 
 <code>checkConnect</code> method with arguments
 <code>p.getAddress().getHostAddress()</code> and
 <code>p.getPort()</code>. Each call to a security manager method
 could result in a SecurityException if the operation is not allowed.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>p</CODE> - the <code>DatagramPacket</code> to be sent.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs.<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkMulticast</code> or <code>checkConnect</code> 
             method doesn't allow the send.<DT><B>See Also: </B><DD><A HREF="../../java/net/DatagramPacket.html"><CODE>DatagramPacket</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkMulticast(java.net.InetAddress)"><CODE>SecurityManager.checkMulticast(InetAddress)</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkConnect(java.lang.String, int)"><CODE>SecurityManager.checkConnect(java.lang.String, int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="receive(java.net.DatagramPacket)"><!-- --></A><H3>
receive</H3>
<PRE>
public void <B>receive</B>(<A HREF="../../java/net/DatagramPacket.html">DatagramPacket</A>&nbsp;p)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Receives a datagram packet from this socket. When this method
 returns, the <code>DatagramPacket</code>'s buffer is filled with
 the data received. The datagram packet also contains the sender's
 IP address, and the port number on the sender's machine.
 <p>
 This method blocks until a datagram is received. The
 <code>length</code> field of the datagram packet object contains
 the length of the received message. If the message is longer than
 the packet's length, the message is truncated.