/* NetworkInterface.java -- Copyright (C) 2002, 2003, 2004, 2005, 2006, 2008 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 gnu.classpath.SystemProperties; import gnu.java.lang.CPStringBuilder; import java.util.Enumeration; import java.util.Iterator; import java.util.Vector; /** * This class models a network interface on the host computer. A network * interface contains a name (typically associated with a specific * hardware adapter) and a list of addresses that are bound to it. * For example, an ethernet interface may be named "eth0" and have the * address 192.168.1.101 assigned to it. * * @author Michael Koch (konqueror@gmx.de) * @since 1.4 */ public final class NetworkInterface { private final VMNetworkInterface netif; private NetworkInterface(VMNetworkInterface netif) { this.netif = netif; } /** Creates an NetworkInterface instance which * represents any interface in the system. Its only * address is 0.0.0.0/0.0.0.0. This * method is needed by {@link MulticastSocket#getNetworkInterface} */ static NetworkInterface createAnyInterface() { return new NetworkInterface(new VMNetworkInterface()); } /** * Returns the name of the network interface * * @return The name of the interface. */ public String getName() { return netif.name; } /** * Returns all available addresses of the network interface * * If a @see SecurityManager is available all addresses are checked * with @see SecurityManager::checkConnect() if they are available. * Only InetAddresses are returned where the security manager * doesn't throw an exception. * * @return An enumeration of all addresses. */ public Enumeration getInetAddresses() { SecurityManager s = System.getSecurityManager(); Vector inetAddresses = new Vector(netif.addresses); if (s == null) return inetAddresses.elements(); Vector tmpInetAddresses = new Vector(1, 1); for (Enumeration addresses = inetAddresses.elements(); addresses.hasMoreElements();) { InetAddress addr = addresses.nextElement(); try { s.checkConnect(addr.getHostAddress(), -1); tmpInetAddresses.add(addr); } catch (SecurityException e) { // Ignore. } } return tmpInetAddresses.elements(); } /** * Returns the display name of the interface * * @return The display name of the interface */ public String getDisplayName() { return netif.name; } /** * Returns an network interface by name * * @param name The name of the interface to return * * @return a NetworkInterface object representing the interface, * or null if there is no interface with that name. * * @exception SocketException If an error occurs * @exception NullPointerException If the specified name is null */ public static NetworkInterface getByName(String name) throws SocketException { if (name == null) throw new NullPointerException(); VMNetworkInterface[] netifs = VMNetworkInterface.getVMInterfaces(); for (int i = 0; i < netifs.length; i++) { if (netifs[i].name.equals(name)) return new NetworkInterface(netifs[i]); } return null; } /** * Return a network interface by its address * * @param addr The address of the interface to return * * @return the interface, or null if none found * * @exception SocketException If an error occurs * @exception NullPointerException If the specified addess is null */ public static NetworkInterface getByInetAddress(InetAddress addr) throws SocketException { if (addr == null) throw new NullPointerException(); VMNetworkInterface[] netifs = VMNetworkInterface.getVMInterfaces(); for (int i = 0; i < netifs.length; i++) { if (netifs[i].addresses.contains(addr)) return new NetworkInterface(netifs[i]); } return null; } /** * Return an Enumeration of all available network interfaces * * @return all interfaces * * @exception SocketException If an error occurs */ public static Enumeration getNetworkInterfaces() throws SocketException { VMNetworkInterface[] netifs = VMNetworkInterface.getVMInterfaces(); Vector networkInterfaces = new Vector(netifs.length); for (int i = 0; i < netifs.length; i++) { if (!netifs[i].addresses.isEmpty()) networkInterfaces.add(new NetworkInterface(netifs[i])); } return networkInterfaces.elements(); } /** * Checks if the current instance is equal to obj * * @param obj The object to compare with * * @return true if equal, false otherwise */ public boolean equals(Object obj) { if (! (obj instanceof NetworkInterface)) return false; NetworkInterface tmp = (NetworkInterface) obj; if (netif.name == null) return tmp.netif.name == null; return (netif.name.equals(tmp.netif.name) && (netif.addresses.equals(tmp.netif.addresses))); } /** * Returns the hashcode of the current instance * * @return the hashcode */ public int hashCode() { // FIXME: hash correctly int hc = netif.addresses.hashCode(); if (netif.name != null) hc += netif.name.hashCode(); return hc; } /** * Returns a string representation of the interface * * @return the string */ public String toString() { // FIXME: check if this is correct CPStringBuilder result; String separator = SystemProperties.getProperty("line.separator"); result = new CPStringBuilder(); result.append("name: "); result.append(getDisplayName()); result.append(" (").append(getName()).append(") addresses:"); result.append(separator); for (Iterator it = netif.addresses.iterator(); it.hasNext(); ) { InetAddress address = (InetAddress) it.next(); result.append(address.toString()).append(";").append(separator); } return result.toString(); } /** * Determines whether this interface is ready to transfer data. * * @return whether the interface is up */ public boolean isUp() throws SocketException { return VMNetworkInterface.isUp(netif.name); } /** * Determines whether this interface does point to point * transmission. * * @return whether the interface does point to point transmission */ public boolean isPointToPoint() throws SocketException { return VMNetworkInterface.isPointToPoint(netif.name); } /** * Determines whether this interface is the loopback interface. * * @return whether the interface is the loopback interface */ public boolean isLoopback() throws SocketException { return VMNetworkInterface.isLoopback(netif.name); } /** * Determines whether this interface supports multicast transmission. * * @return whether the interface supports multicast transmission. */ public boolean supportsMulticast() throws SocketException { return VMNetworkInterface.supportsMulticast(netif.name); } }