| /* SelectorProvider.java |
| Copyright (C) 2002, 2003, 2004 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.nio.channels.spi; |
| |
| import gnu.java.nio.SelectorProviderImpl; |
| |
| import java.io.IOException; |
| import java.nio.channels.DatagramChannel; |
| import java.nio.channels.Pipe; |
| import java.nio.channels.ServerSocketChannel; |
| import java.nio.channels.SocketChannel; |
| |
| |
| /** |
| * @author Michael Koch |
| * @since 1.4 |
| */ |
| public abstract class SelectorProvider |
| { |
| private static SelectorProvider systemDefaultProvider; |
| |
| /** |
| * Initializes the selector provider. |
| * |
| * @exception SecurityException If a security manager has been installed and |
| * it denies @see RuntimePermission ("selectorProvider"). |
| */ |
| protected SelectorProvider() |
| { |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) |
| sm.checkPermission(new RuntimePermission("selectorProvider")); |
| } |
| |
| /** |
| * Opens a datagram channel. |
| * |
| * @return a new datagram channel object |
| * |
| * @exception IOException if an error occurs |
| */ |
| public abstract DatagramChannel openDatagramChannel() |
| throws IOException; |
| |
| /** |
| * Opens a pipe. |
| * |
| * @return a new pipe object |
| * |
| * @exception IOException if an error occurs |
| */ |
| public abstract Pipe openPipe() throws IOException; |
| |
| /** |
| * Opens a selector. |
| * |
| * @return a new selector object |
| * |
| * @exception IOException if an error occurs |
| */ |
| public abstract AbstractSelector openSelector() throws IOException; |
| |
| /** |
| * Opens a server socket channel. |
| * |
| * @return a new server socket channel object |
| * |
| * @exception IOException if an error occurs |
| */ |
| public abstract ServerSocketChannel openServerSocketChannel() |
| throws IOException; |
| |
| /** |
| * Opens a socket channel. |
| * |
| * @return a new socket channel object |
| * |
| * @exception IOException if an error occurs |
| */ |
| public abstract SocketChannel openSocketChannel() throws IOException; |
| |
| /** |
| * Returns the system-wide default selector provider for this invocation |
| * of the Java virtual machine. |
| * |
| * @return the default seletor provider |
| */ |
| public static synchronized SelectorProvider provider() |
| { |
| if (systemDefaultProvider == null) |
| { |
| String propertyValue = |
| System.getProperty("java.nio.channels.spi.SelectorProvider"); |
| |
| if (propertyValue == null || propertyValue.equals("")) |
| systemDefaultProvider = new SelectorProviderImpl(); |
| else |
| { |
| try |
| { |
| systemDefaultProvider = |
| (SelectorProvider) Class.forName(propertyValue) |
| .newInstance(); |
| } |
| catch (Exception e) |
| { |
| System.err.println("Could not instantiate class: " |
| + propertyValue); |
| systemDefaultProvider = new SelectorProviderImpl(); |
| } |
| } |
| } |
| |
| return systemDefaultProvider; |
| } |
| } |