The method SSLSocketImpl::closeSocket has the below code snippet,

if (appInput.readLock.tryLock()) {
    int soTimeout = getSoTimeout();
    try {
        // deplete could hang on the skip operation
        // in case of infinite socket read timeout.
        // Change read timeout to avoid deadlock.
        // This workaround could be replaced later
        // with the right synchronization
        if (soTimeout == 0)
            setSoTimeout(DEFAULT_SKIP_TIMEOUT);
        inputRecord.deplete(false);
    } catch (java.net.SocketTimeoutException stEx) {
        // skip timeout exception during deplete
    } finally {
        if (soTimeout == 0)
            setSoTimeout(soTimeout);
        appInput.readLock.unlock();
    }
}

If getSoTimeout() throws an exception, say SocketException, appInput.readLock.unlock() cannot be called.