}

        return derived;
    }

    /**
     * Generate a random key
     *
     * @param length key length in bytes
     * @return random key bytes
     */
    public byte[] generateRandomKey(int length) {
        checkNotClosed();

        byte[] key = new byte[length];
        secureRandom.nextBytes(key);
        return key;
    }

    /**
     * Clear all stored keys
     */

        }
    }

    @Test
    public void testGenerateRandomKey() {
        byte[] key1 = keyManager.generateRandomKey(32);
        byte[] key2 = keyManager.generateRandomKey(32);

        assertNotNull(key1, "Should generate key 1");
        assertNotNull(key2, "Should generate key 2");
        assertEquals(32, key1.length, "Key 1 should have correct length");