看这个源文件吧,这里的serversocket的方法,只有
public static synchronized void setSocketFactory(SocketImplFactory fac) throws IOException
是可以调用的。你可把accept(),改成public static socket accept() throws IOException
/*
* @(#)ServerSocket.java 1.43 01/01/21
*
* Copyright 1995-2001 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the confidential and proprietary information
* of Sun Microsystems, Inc. ("Confidential Information"). You
* shall not disclose such Confidential Information and shall use
* it only in accordance with the terms of the license agreement
* you entered into with Sun.
*
*/
package java.net;
import java.io.IOException;
import java.io.FileDescriptor;
/**
* This class implements server sockets. A server socket waits for
* requests to come in over the network. It performs some operation
* based on that request, and then
possibly returns a result to the requester.
* <p>
* The actual work of the server socket is performed by an instance
* of the <code>SocketImpl</code> class. An application can
* change the socket factory that creates the socket
* implementation to configure itself to create sockets
* appropriate to the local firewall.
*
* @author unascribed
* @version 1.43, 01/21/01
* @see java.net.SocketImpl
* @see java.net.ServerSocket#setSocketFactory(java.net.SocketImplFactory)
* @since JDK1.0
*/
public
class ServerSocket {
/**
* The implementation of this Socket.
*/
private SocketImpl impl;
/**
* Creates an unconnected server socket. Note: this method
* should not be public.
* @exception IOException IO error when opening the socket.
*/
private ServerSocket() throws IOException {
impl = (factory != null) ? factory.createSocketImpl() :
new PlainSocketImpl();
}
/**
* Creates a server socket on a specified port. A port of
* <code>0</code> creates a socket on any free port.
* <p>
* The maximum queue length for incoming connection indications (a
* request to connect) is set to <code>50</code>. If a connection
* indication arrives when the queue is full, the connection is refused.
* <p>
* If the application has specified a server socket factory, that
* factory's <code>createSocketImpl</code> method is called to create
* the actual socket implementation. Otherwise a "plain" socket is created.
* <p>
* If there is a security manager,
* its <code>checkListen</code> method is called
* with the <code>port</code> argument
* as its argument to ensure the operation is allowed.
* This could result in a SecurityException.
*
* @param port the port number, or <code>0</code> to use any
* free port.
*
* @exception IOException if an I/O error occurs when opening the socket.
* @exception SecurityException
* if a security manager exists and its <code>checkListen</code>
* methoddo
esn't allow the operation.
*
* @see java.net.SocketImpl
* @see java.net.SocketImplFactory#createSocketImpl()
* @see java.net.ServerSocket#setSocketFactory(java.net.SocketImplFactory)
* @see SecurityManager#checkListen
*/
public ServerSocket(int port) throws IOException {
this(port, 50, null);
}
/**
* Creates a server socket and binds it to the specified local port
* number, with the specified backlog.
* A port number of <code>0</code> creates a socket on any
* free port.
* <p>
* The maximum queue length for incoming connection indications (a
* request to connect) is set to the <code>backlog</code> parameter. If
* a connection indication arrives when the queue is full, the
* connection is refused.
* <p>
* If the application has specified a server socket factory, that
* factory's <code>createSocketImpl</code> method is called to create
* the actual socket implementation. Otherwise a "plain" socket is created.
* <p>
* If there is a security manager,
* its <code>checkListen</code> method is called
* with the <code>port</code> argument
* as its argument to ensure the operation is allowed.
* This could result in a SecurityException.
*
* @param port the specified port, or <code>0</code> to use
* any free port.
* @param backlog the maximum length of the queue.
*
* @exception IOException if an I/O error occurs when opening the socket.
* @exception SecurityException
* if a security manager exists and its <code>checkListen</code>
* methoddo
esn't allow the operation.
*
* @see java.net.SocketImpl
* @see java.net.SocketImplFactory#createSocketImpl()
* @see java.net.ServerSocket#setSocketFactory(java.net.SocketImplFactory)
* @see SecurityManager#checkListen
*/
public ServerSocket(int port, int backlog) throws IOException {
this(port, backlog, null);
}
/**
* Create a server with the specified port, listen backlog, and
* local IP address to bind to. The <i>bindAddr</i> argument
* can be used on a multi-homed host for a ServerSocket that
* will only accept connect requests to one of its addresses.
* If <i>bindAddr</i> is null, it will default accepting
* connections on any/all local addresses.
* The port must be between 0 and 65535, inclusive.
*
* <P>If there is a security manager, this method
* calls its <code>checkListen</code> method
* with the <code>port</code> argument
* as its argument to ensure the operation is allowed.
* This could result in a SecurityException.
*
* <P>
* @param port the local TCP port
* @param backlog the listen backlog
* @param bindAddr the local InetAddress the server will bind to
*
* @throws SecurityException if a security manager exists and
* its <code>checkListen</code> methoddo
esn't allow the operation.
*
* @throws IOException if an I/O error occurs when opening the socket.
*
* @see SocketOptions
* @see SocketImpl
* @see SecurityManager#checkListen
* @since JDK1.1
*/
public ServerSocket(int port, int backlog, InetAddress bindAddr) throws IOException {
this();
if (port < 0 || port > 0xFFFF)
throw new IllegalArgumentException(
"Port value out of range: " + port);
try {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkListen(port);
}
impl.create(true);
// a stream socket
if (bindAddr == null)
bindAddr = InetAddress.anyLocalAddress;
impl.bind(bindAddr, port);
impl.listen(backlog);
} catch(SecurityException e) {
impl.close();
throw e;
} catch(IOException e) {
impl.close();
throw e;
}
}
/**
* Returns the local address of this server socket.
*
* @return the address to which this socket is connected,
* or <code>null</code> if the socket is not yet connected.
*/
public InetAddress getInetAddress() {
return impl.getInetAddress();
}
/**
* Returns the port on which this socket is listening.
*
* @return the port number to which this socket is listening.
*/
public int getLocalPort() {
return impl.getLocalPort();
}
/**
* Listens for a connection to be made to this socket and accepts
* it. The method blocks until a connection is made.
*
* <p>A new Socket <code>s</code> is created and, if there
* is a security manager,
* the security manager's <code>checkAccept</code> method is called
* with <code>s.getInetAddress().getHostAddress()</code> and
* <code>s.getPort()</code>
* as its arguments to ensure the operation is allowed.
* This could result in a SecurityException.
*
* @exception IOException if an I/O error occurs when waiting for a
* connection.
* @exception SecurityException if a security manager exists and its
* <code>checkListen</code> methoddo
esn't allow the operation.
* @return the new Socket
* @see SecurityManager#checkAccept
*/
public Socket accept() throws IOException {
Socket s = new Socket();
implAccept(s);
return s;
}
/**
* Subclasses of ServerSocket use this method to override accept()
* to return their own subclass of socket. So a FooServerSocket
* will typically hand this method an <i>empty</i> FooSocket. On
* return from implAccept the FooSocket will be connected to a client.
*
* @param s the Socket
* @throws IOException if an I/O error occurs when waiting
* for a connection.
* @since JDK1.1
*/
protected final void implAccept(Socket s) throws IOException {
SocketImpl si = s.impl;
try {
s.impl = null;
si.address = new InetAddress();
si.fd = new FileDescriptor();
impl.accept(si);
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkAccept(si.getInetAddress().getHostAddress(),
si.getPort());
}
} catch (IOException e) {
si.reset();
throw e;
} catch (SecurityException e) {
si.reset();
throw e;
} finally {
s.impl = si;
}
}
/**
* Closes this socket.
*
* @exception IOException if an I/O error occurs when closing the socket.
*/
public void close() throws IOException {
impl.close();
}
/**
* Enable/disable SO_TIMEOUT with the specified timeout, in
* milliseconds. With this option set to a non-zero timeout,
* a call to accept() for this ServerSocket
* will block for only this amount of time. If the timeout expires,
* a <B>java.io.InterruptedIOException</B> is raised, though the
* ServerSocket is still valid. The option <B>must</B> be enabled
* prior to entering the blocking operation to have effect. The
* timeout must be > 0.
* A timeout of zero is interpreted as an infinite timeout.
* @param timeout the specified timeout, in milliseconds
* @exception SocketException if there is an error in
* the underlying protocol, such as a TCP error.
* @since JDK1.1
* @see #getSoTimeout()
*/
public synchronized void setSoTimeout(int timeout) throws SocketException {
impl.setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
}
/**
* Retrive setting for SO_TIMEOUT. 0 returns implies that the
* option is disabled (i.e., timeout of infinity).
* @return the SO_TIMEOUT value
* @exception IOException if an I/O error occurs
* @since JDK1.1
* @see #setSoTimeout(int)
*/
public synchronized int getSoTimeout() throws IOException {
Object o = impl.getOption(SocketOptions.SO_TIMEOUT);
/* extra type safety */
if (o instanceof Integer) {
return ((Integer) o).intValue();
} else
{
return 0;
}
}
/**
* Returns the implementation address and implementation port of
* this socket as a <code>String</code>.
*
* @return a string representation of this socket.
*/
public String toString() {
return "ServerSocket[addr=" + impl.getInetAddress() +
",port=" + impl.getPort() +
",localport=" + impl.getLocalPort() + "]";
}
/**
* The factory for all server sockets.
*/
private static SocketImplFactory factory;
/**
* Sets the server socket implementation factory for the
* application. The factory can be specified only once.
* <p>
* When an application creates a new server socket, the socket
* implementation factory's <code>createSocketImpl</code> method is
* called to create the actual socket implementation.
* <p>
* If there is a security manager, this method first calls
* the security manager's <code>checkSetFactory</code> method
* to ensure the operation is allowed.
* This could result in a SecurityException.
*
* @param fac the desired factory.
* @exception IOException if an I/O error occurs when setting the
* socket factory.
* @exception SocketException if the factory has already been defined.
* @exception SecurityException if a security manager exists and its
* <code>checkSetFactory</code> methoddo
esn't allow the operation.
* @see java.net.SocketImplFactory#createSocketImpl()
* @see SecurityManager#checkSetFactory
*/
public static synchronized void setSocketFactory(SocketImplFactory fac) throws IOException {
if (factory != null) {
throw new SocketException("factory already defined");
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkSetFactory();
}
factory = fac;
}
}