Java Utililty Methods HTTP Port Find

ServerSocket ss = null;
try {
    ss = new ServerSocket();
    ss.bind(null);
    return ss.getLocalPort();
} catch (IOException e) {
    throw new IllegalStateException("", e);
} finally {
...

if (basePort == 0) {
    return getAvailablePort();
if (basePort < 0 || basePort > 65535) {
    throw new IllegalArgumentException("Illegal port number: " + basePort);
for (int i = basePort; i <= 65535; i++) {
    if (isPortAvailable(i)) {
...

try {
    ServerSocket ss = new ServerSocket(defaultPort);
    ss.close();
    return defaultPort;
} catch (IOException e) {
ServerSocket ss = new ServerSocket(0);
int port = ss.getLocalPort();
...

int result = port;
while (true) {
    if (isPortAvailable(result)) {
        break;
    result++;
return result;
...

ServerSocket socket = null;
for (int i = 0; i < 2048; i++) {
    try {
        socket = new ServerSocket(port + i);
    } catch (Exception e) {
    } finally {
        if (null != socket) {
            try {
...

int localPort = -1;
try (ServerSocket socket = new ServerSocket(prefferedPort)) {
    localPort = socket.getLocalPort();
} catch (IOException exp) {
    if (prefferedPort > 0) {
        return getAvailablePort(0);
return localPort;

ArrayList<Integer> failedPorts = new ArrayList<Integer>(randomAttempts);
Random randomNum = new Random();
int randomPort = MAX_PORT_NUMBER;
while (randomAttempts > 0) {
    randomPort = randomNum.nextInt(MAX_PORT_NUMBER - MIN_PORT_NUMBER) + MIN_PORT_NUMBER;
    if (checkIfPortAvailable(randomPort)) {
        return randomPort;
    failedPorts.add(randomPort);
    randomAttempts--;
randomPort = MAX_PORT_NUMBER;
while (true) {
    if (!failedPorts.contains(randomPort) && checkIfPortAvailable(randomPort)) {
        return randomPort;
    randomPort--;

int port = startPort;
while (_assignedPorts.contains(port) && !portAvailable(port) && port < 0x7FFFFFFF) {
    port++;
if (0x7FFFFFFF == port) {
    throw new RuntimeException("no available port found starting at " + startPort);
_assignedPorts.add(port);
...

StringTokenizer st = new StringTokenizer(portRange, ",");
while (st.hasMoreTokens()) {
    int index = portRange.indexOf('-');
    if (index == -1) {
        int port = Integer.parseInt(st.nextToken().trim());
        if (port == 0) {
            return 0;
        try {
            return getPort(port);
        } catch (IOException e) {
    } else {
        int startPort = Integer.parseInt(portRange.substring(0, index));
        int endPort = Integer.parseInt(portRange.substring(index + 1));
        if (endPort < startPort) {
            throw new IllegalArgumentException(
                    "Start port [" + startPort + "] must be greater than end port [" + endPort + "]");
        for (int i = startPort; i <= endPort; i++) {
            try {
                return getPort(i);
            } catch (IOException ex) {
throw new IOException("Failed to get free port from [" + portRange + "]");

List<Integer> availablePorts = new ArrayList<Integer>();
int port = basePort;
for (int i = 0; i < portCount; i++) {
    while (!isPortAvailable(port)) {
        port++;
    availablePorts.add(port++);
return availablePorts;