test/kafka/src/main/java/org/apache/rya/test/kafka/PortUtils.java

/*
 * 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.rya.test.kafka;

import java.io.IOException;
import java.net.ServerSocket;
import java.security.SecureRandom;

public class PortUtils {

    private PortUtils() {}

    public static int getRandomFreePort() {
        final SecureRandom r = new SecureRandom();
        int count = 0;

        while (count < 13) {
            final int port = r.nextInt((1 << 16) - 1024) + 1024;

            try (ServerSocket so = new ServerSocket(port)) {
                so.setReuseAddress(true);
                return port;
            } catch (final IOException e) {
                // ignore
            }

            count++;
        }

        throw new RuntimeException("Unable to find port");
    }
}