// Then
        DfFinalTimeZoneProvider provider = getDBFluteSystemTimeZoneProvider();
        if (provider != null) {
            TimeZone providedTimeZone = provider.provide();
            assertEquals(FessUserTimeZoneProcessProvider.centralTimeZone, providedTimeZone);
        } else {
            // Cannot test due to reflection access limitations
            assertTrue("Cannot access DBFluteSystem fields via reflection", true);
        }

        assertEquals(TimeZone.getDefault(), FessUserTimeZoneProcessProvider.centralTimeZone);

        // Verify it's the same instance for all provider instances
        FessUserTimeZoneProcessProvider provider1 = new FessUserTimeZoneProcessProvider();
        FessUserTimeZoneProcessProvider provider2 = new FessUserTimeZoneProcessProvider();

        TimeZone tz1 = provider1.getRequestedTimeZone(requestManager);

        }
    }

    // Test centralTimeZone reference
    public void test_centralTimeZone() {
        // Test that centralTimeZone is accessible and not null
        TimeZone centralTz = FessUserTimeZoneProcessProvider.centralTimeZone;
        assertNotNull(centralTz);
        assertEquals(TimeZone.getDefault(), centralTz);
    }

    // Test toString method
    public void test_toString() {