content: /**
   * Licensed 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.aurora.common.net;
  
  import java.net.InetSocketAddress;
  
  import com.google.common.base.Preconditions;
  
  import org.apache.commons.lang.StringUtils;
  
  /**
   * A utility that can parse [host]:[port] pairs or :[port] designators into instances of
   * {@link java.net.InetSocketAddress}. The literal '*' can be specified for port as an alternative
   * to '0' to indicate any local port.
   *
   * @author John Sirois
   */
  public final class InetSocketAddressHelper {
  
    /**
     * Attempts to parse an endpoint spec into an InetSocketAddress.
     *
     * @param value the endpoint spec
     * @return a parsed InetSocketAddress
     * @throws NullPointerException     if {@code value} is {@code null}
     * @throws IllegalArgumentException if {@code value} cannot be parsed
     */
    public static InetSocketAddress parse(String value) {
      Preconditions.checkNotNull(value);
  
      String[] spec = value.split(":", 2);
      if (spec.length != 2) {
        throw new IllegalArgumentException("Invalid socket address spec: " + value);
      }
  
      String host = spec[0];
      int port = asPort(spec[1]);
  
      return StringUtils.isEmpty(host)
          ? new InetSocketAddress(port)
          : InetSocketAddress.createUnresolved(host, port);
    }
  
    /**
     * Attempts to return a usable String given an InetSocketAddress.
     *
     * @param value the InetSocketAddress.
     * @return the String representation of the InetSocketAddress.
     */
    public static String toString(InetSocketAddress value) {
      Preconditions.checkNotNull(value);
      return value.getHostName() + ":" + value.getPort();
    }
  
    private static int asPort(String port) {
      if ("*".equals(port)) {
        return 0;
      }
      try {
        return Integer.parseInt(port);
      } catch (NumberFormatException e) {
        throw new IllegalArgumentException("Invalid port: " + port, e);
      }
    }
  
    private InetSocketAddressHelper() {
      // utility
    }
  }
  