private void cleanThreadLocals() {

        try {

            // Get a reference to the thread locals table of the current thread

            Thread thread = Thread.currentThread();

            Field threadLocalsField = Thread.class.getDeclaredField("threadLocals");

            threadLocalsField.setAccessible(true);

            Object threadLocalTable = threadLocalsField.get(thread);

            // Get a reference to the array holding the thread local variables inside the

            // ThreadLocalMap of the current thread

            Class threadLocalMapClass = Class.forName("java.lang.ThreadLocal$ThreadLocalMap");

            Field tableField = threadLocalMapClass.getDeclaredField("table");

            tableField.setAccessible(true);

            Object table = tableField.get(threadLocalTable);

            // The key to the ThreadLocalMap is a WeakReference object. The referent field of this object

            // is a reference to the actual ThreadLocal variable

            Field referentField = Reference.class.getDeclaredField("referent");

            referentField.setAccessible(true);

            for (int i=0; i < Array.getLength(table); i++) {

                // Each entry in the table array of ThreadLocalMap is an Entry object

                // representing the thread local reference and its value

                Object entry = Array.get(table, i);

                if (entry != null) {

                    // Get a reference to the thread local object and remove it from the table

                    ThreadLocal threadLocal = (ThreadLocal)referentField.get(entry);

                    threadLocal.remove();

                }

            }

        } catch(Exception e) {

            // We will tolerate an exception here and just log it

            throw new IllegalStateException(e);

        }

    }