Java Utililty Methods Socket Check

boolean isConnected(Socket socket)
is Connected

return socket != null && socket.isBound() && !socket.isClosed() && socket.isConnected()
 && !socket.isInputShutdown() && !socket.isOutputShutdown();

boolean isSocketClosed(SocketException e)
is Socket Closed

return e.getMessage().equals("Socket closed");

boolean isSocketReadyToWrite(Socket socket)
Determines if the socket can be written to.

OutputStream out = socket.getOutputStream();
try {
 out.write(0);
 out.flush();
 out.write(0);
 out.flush();
} catch (SocketException e) {
 return false;
...

boolean isSocketTimeoutException(final InterruptedIOException e)
If SocketTimeoutExceptionClass is defined, returns true only if the exception is an instance of SocketTimeoutExceptionClass.

return e instanceof SocketTimeoutException;