| /* SocketImpl.java -- Abstract socket implementation class |
| Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 |
| Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.net; |
| |
| import java.io.FileDescriptor; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| |
| /* Written using on-line Java Platform 1.2 API Specification. |
| * Believed complete and correct. |
| */ |
| |
| /** |
| * This abstract class serves as the parent class for socket implementations. |
| * The implementation class serves an intermediary to native routines that |
| * perform system specific socket operations. |
| * <p> |
| * A default implementation is provided by the system, but this can be |
| * changed via installing a <code>SocketImplFactory</code> (through a call |
| * to the static method <code>Socket.setSocketImplFactory</code>). A |
| * subclass of <code>Socket</code> can also pass in a <code>SocketImpl</code> |
| * to the <code>Socket(SocketImpl)</code> constructor to use an |
| * implementation different from the system default without installing |
| * a factory. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Per Bothner (bothner@cygnus.com) |
| */ |
| public abstract class SocketImpl implements SocketOptions |
| { |
| /** |
| * The address of the remote end of the socket connection |
| */ |
| protected InetAddress address; |
| |
| /** |
| * A FileDescriptor object representing this socket connection. |
| */ |
| protected FileDescriptor fd; |
| |
| /** |
| * The port number the socket is bound to locally |
| */ |
| protected int localport = -1; |
| |
| /** |
| * The port number of the remote end of the socket connection |
| */ |
| protected int port; |
| |
| /** |
| * Default, no-argument constructor for use by subclasses. |
| */ |
| public SocketImpl() |
| { |
| } |
| |
| /** |
| * Creates a new socket that is not bound to any local address/port and |
| * is not connected to any remote address/port. This will be created as |
| * a stream socket if the stream parameter is true, or a datagram socket |
| * if the stream parameter is false. |
| * |
| * @param stream true for a stream socket, false for a datagram socket |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void create(boolean stream) throws IOException; |
| |
| /** |
| * Connects to the remote hostname and port specified as arguments. |
| * |
| * @param host The remote hostname to connect to |
| * @param port The remote port to connect to |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void connect(String host, int port) |
| throws IOException; |
| |
| /** |
| * Connects to the remote address and port specified as arguments. |
| * |
| * @param host The remote address to connect to |
| * @param port The remote port to connect to |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void connect(InetAddress host, int port) |
| throws IOException; |
| |
| /** |
| * Connects to the socket to the host specified in address. This |
| * method blocks until successful connected or the timeout occurs. |
| * A timeout of zero means no timout. |
| * |
| * @param address Data of remote host |
| * @param timeout time to wait to stop connecting |
| * |
| * @exception IOException If an error occurs |
| * |
| * @since 1.4 |
| */ |
| protected abstract void connect(SocketAddress address, int timeout) |
| throws IOException; |
| |
| /** |
| * Binds to the specified port on the specified addr. Note that this addr |
| * must represent a local IP address. |
| * <p> |
| * Note that it is unspecified how to bind to all interfaces on the localhost |
| * (INADDR_ANY). |
| * |
| * @param host The address to bind to |
| * @param port The port number to bind to |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void bind(InetAddress host, int port) |
| throws IOException; |
| |
| /** |
| * Starts listening for connections on a socket. The backlog parameter |
| * is how many pending connections will queue up waiting to be serviced |
| * before being accept'ed. If the queue of pending requests exceeds this |
| * number, additional connections will be refused. |
| * |
| * @param backlog The length of the pending connection queue |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void listen(int backlog) throws IOException; |
| |
| /** |
| * Accepts a connection on this socket. |
| * |
| * @param s The implementation object for the accepted connection. |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void accept(SocketImpl s) throws IOException; |
| |
| /** |
| * Returns an <code>InputStream</code> object for reading from this socket. |
| * |
| * @return An <code>InputStream</code> for reading from this socket. |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract InputStream getInputStream() throws IOException; |
| |
| /** |
| * Returns an <code>OutputStream</code> object for writing to this socket |
| * |
| * @return An <code>OutputStream</code> for writing to this socket. |
| * |
| * @exception IOException If an error occurs. |
| */ |
| protected abstract OutputStream getOutputStream() throws IOException; |
| |
| /** |
| * Returns the number of bytes that the caller can read from this socket |
| * without blocking. |
| * |
| * @return The number of readable bytes before blocking |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract int available() throws IOException; |
| |
| /** |
| * Closes the socket. This will normally cause any resources, such as the |
| * InputStream, OutputStream and associated file descriptors to be freed. |
| * <p> |
| * Note that if the SO_LINGER option is set on this socket, then the |
| * operation could block. |
| * |
| * @exception IOException If an error occurs |
| */ |
| protected abstract void close() throws IOException; |
| |
| /** |
| * Returns the FileDescriptor objects for this socket. |
| * |
| * @return A FileDescriptor for this socket. |
| */ |
| protected FileDescriptor getFileDescriptor() |
| { |
| return fd; |
| } |
| |
| /** |
| * Returns the remote address this socket is connected to |
| * |
| * @return The remote address |
| */ |
| protected InetAddress getInetAddress() |
| { |
| return address; |
| } |
| |
| /** |
| * Returns the remote port this socket is connected to |
| * |
| * @return The remote port |
| */ |
| protected int getPort() |
| { |
| return port; |
| } |
| |
| /** |
| * Returns true or false when this socket supports sending urgent data |
| * or not. |
| * |
| * @return true if the socket implementation supports sending urgent data, |
| * false otherwise |
| * |
| * @since 1.4 |
| */ |
| protected boolean supportsUrgentData() |
| { |
| // This method has to be overwritten by socket classes that support |
| // sending urgend data. |
| return false; |
| } |
| |
| /** |
| * Sends one byte of urgent data to the socket. |
| * |
| * @param data The byte to send, the low eight bits of it |
| * |
| * @exception IOException If an error occurs |
| * |
| * @since 1.4 |
| */ |
| protected abstract void sendUrgentData(int data) throws IOException; |
| |
| /** |
| * Returns the local port this socket is bound to |
| * |
| * @return The local port |
| */ |
| protected int getLocalPort() |
| { |
| return localport; |
| } |
| |
| /** |
| * Returns a <code>String</code> representing the remote host and port of |
| * this socket. |
| * |
| * @return A <code>String</code> for this socket. |
| */ |
| public String toString() |
| { |
| return "[addr=" |
| + ((address == null) ? "0.0.0.0/0.0.0.0" : address.toString()) |
| + ",port=" + port + ",localport=" + localport + "]"; |
| } |
| |
| /** |
| * Shut down the input side of this socket. Subsequent reads will |
| * return end-of-file. |
| * |
| * @exception IOException if an error occurs |
| */ |
| protected void shutdownInput() throws IOException |
| { |
| throw new IOException("Not implemented in this socket class"); |
| } |
| |
| /** |
| * Shut down the output side of this socket. Subsequent writes will |
| * fail with an IOException. |
| * |
| * @exception IOException if an error occurs |
| */ |
| protected void shutdownOutput() throws IOException |
| { |
| throw new IOException("Not implemented in this socket class"); |
| } |
| } |