Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.wake.remote.address;
020
021import org.apache.reef.tang.Configuration;
022import org.apache.reef.tang.Tang;
023import org.apache.reef.wake.exception.WakeRuntimeException;
024
025import javax.inject.Inject;
026import java.net.Inet4Address;
027import java.net.InetAddress;
028import java.net.NetworkInterface;
029import java.net.SocketException;
030import java.util.Comparator;
031import java.util.Enumeration;
032import java.util.TreeSet;
033import java.util.concurrent.atomic.AtomicReference;
034import java.util.logging.Level;
035import java.util.logging.Logger;
036
037/**
038 * An implementation of LocalAddressProvider using the (removed) code from NetUtils.getLocalAddress().
039 * @deprecated in 0.14. Use HostnameBasedLocalAddressProvider instead
040 */
041@Deprecated
042public final class LegacyLocalAddressProvider implements LocalAddressProvider {
043  private static final Logger LOG = Logger.getLogger(LegacyLocalAddressProvider.class.getName());
044  private final AtomicReference<String> cached = new AtomicReference<>();
045
046  /**
047   * Injectable constructor for Tang only.
048   */
049  @Inject
050  private LegacyLocalAddressProvider() {
051    LOG.log(Level.FINE, "Instantiating LegacyLocalAddressProvider");
052  }
053
054  @Override
055  public String getLocalAddress() {
056    // This method is surprisingly slow: It was causing unit test timeouts, so we memoize the result.
057    if (cached.get() == null) {
058      final Enumeration<NetworkInterface> ifaces;
059      try {
060        ifaces = NetworkInterface.getNetworkInterfaces();
061        final TreeSet<Inet4Address> sortedAddrs = new TreeSet<>(new AddressComparator());
062        // There is an idea of virtual / subinterfaces exposed by java here.
063        // We're not walking around looking for those because the javadoc says:
064
065        // "NOTE: can use getNetworkInterfaces()+getInetAddresses() to obtain all IP addresses for this node"
066
067        while (ifaces.hasMoreElements()) {
068          final NetworkInterface iface = ifaces.nextElement();
069//          if(iface.isUp()) {  // leads to slowness and non-deterministic return values, so don't call isUp().
070          final Enumeration<InetAddress> addrs = iface.getInetAddresses();
071          while (addrs.hasMoreElements()) {
072            final InetAddress a = addrs.nextElement();
073            if (a instanceof Inet4Address) {
074              sortedAddrs.add((Inet4Address) a);
075            }
076//            }
077          }
078        }
079        if (sortedAddrs.isEmpty()) {
080          throw new WakeRuntimeException("This machine apparently doesn't have any IP addresses (not even 127.0.0.1) " +
081              "on interfaces that are up.");
082        }
083        cached.set(sortedAddrs.pollFirst().getHostAddress());
084        LOG.log(Level.FINE, "Local address is {0}", cached.get());
085      } catch (final SocketException e) {
086        throw new WakeRuntimeException("Unable to get local host address", e);
087      }
088    }
089    return cached.get();
090  }
091
092  @Override
093  public Configuration getConfiguration() {
094    return Tang.Factory.getTang().newConfigurationBuilder()
095        .bind(LocalAddressProvider.class, LegacyLocalAddressProvider.class)
096        .build();
097  }
098
099  private static class AddressComparator implements Comparator<Inet4Address> {
100
101    // get unsigned byte.
102    private static int u(final byte b) {
103      return (int) b; // & 0xff;
104    }
105
106    @Override
107    public int compare(final Inet4Address aa, final Inet4Address ba) {
108      final byte[] a = aa.getAddress();
109      final byte[] b = ba.getAddress();
110      // local subnet comes after all else.
111      if (a[0] == 127 && b[0] != 127) {
112        return 1;
113      }
114      if (a[0] != 127 && b[0] == 127) {
115        return -1;
116      }
117      for (int i = 0; i < 4; i++) {
118        if (u(a[i]) < u(b[i])) {
119          return -1;
120        }
121        if (u(a[i]) > u(b[i])) {
122          return 1;
123        }
124      }
125      return 0;
126    }
127  }
128}