Java HTTP Port Find randomFreePort()

Description

random Free Port

License

Apache License

Declaration

public static int randomFreePort() 

Method Source Code

//package com.java2s;
/**/*from  www  . ja  v a 2 s  .co m*/
 * Copyright 2009 The Apache Software Foundation
 *
 * 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.
 */

import java.io.IOException;

import java.net.ServerSocket;

import java.util.Random;

public class Main {
    private static final int MIN_RANDOM_PORT = 0xc000;
    private static final int MAX_RANDOM_PORT = 0xfffe;

    public static int randomFreePort() {
        int port = 0;
        do {
            port = randomPort();
            try {
                ServerSocket sock = new ServerSocket(port);
                sock.close();
            } catch (IOException ex) {
                port = 0;
            }
        } while (port == 0);
        return port;
    }

    /**
     * Returns a random port. These ports cannot be registered with IANA and are
     * intended for dynamic allocation (see http://bit.ly/dynports).
     */
    public static int randomPort() {
        return MIN_RANDOM_PORT + new Random().nextInt(MAX_RANDOM_PORT - MIN_RANDOM_PORT);
    }
}

Related

1. parsePort(String s)
2. ping(String domain, int port)
3. pingServer(String host, Integer port)
4. randomAvailablePort()
5. randomFreePort()
6. randomFreePort()
7. read(String host, int port)
8. readHttpContent(String domain, String resource, int port)
9. replace(final String host, final int port, final String user, final String program, final String relation, final String dataset, final String format)