org.apache.pinot.spi.utils.NetUtils Maven / Gradle / Ivy

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.pinot.spi.utils;

import java.io.IOException;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.SocketException;
import java.net.UnknownHostException;


public class NetUtils {
  private NetUtils() {
  }

  private static final String DUMMY_OUT_IP = "74.125.224.0";

  /**
   * Get the ip address of local host.
   */
  public static String getHostAddress()
      throws SocketException, UnknownHostException {
    DatagramSocket ds = new DatagramSocket();
    ds.connect(InetAddress.getByName(DUMMY_OUT_IP), 80);
    InetAddress localAddress = ds.getLocalAddress();
    if (localAddress.getHostAddress().equals("0.0.0.0")) {
      localAddress = InetAddress.getLocalHost();
    }
    return localAddress.getHostAddress();
  }

  /**
   * Get the hostname or IP address.
   *
   * @return The hostname if available, otherwise a dotted quad address. Returns null if neither can be determined.
   */
  public static String getHostnameOrAddress() {
    try {
      return InetAddress.getLocalHost().getCanonicalHostName();
    } catch (UnknownHostException ignored) {
      try {
        return getHostAddress();
      } catch (Exception e) {
        return null;
      }
    }
  }

  /**
   * Find an open port.
   * @return an open port
   * @throws IOException
   */
  public static int findOpenPort()
      throws IOException {
    try (ServerSocket socket = new ServerSocket(0)) {
      return socket.getLocalPort();
    }
  }

  /**
   * Find the first open port from default port in an incremental order.
   * @param basePort
   * @return an open port
   */
  public static int findOpenPort(int basePort) {
    while (!available(basePort)) {
      basePort++;
    }
    return basePort;
  }

  /**
   * Checks to see if a specific port is available.
   *
   * @param port the port to check for availability
   */
  public static boolean available(int port) {
    ServerSocket ss = null;
    DatagramSocket ds = null;
    try {
      ss = new ServerSocket(port);
      ss.setReuseAddress(true);
      ds = new DatagramSocket(port);
      ds.setReuseAddress(true);
      return true;
    } catch (IOException e) {
      return false;
    } finally {
      if (ds != null) {
        ds.close();
      }
      if (ss != null) {
        try {
          ss.close();
        } catch (IOException e) {
          /* should not be thrown */
        }
      }
    }
  }
}