public TestNameTestDirectoryProvider tmpDir = new TestNameTestDirectoryProvider(getClass());
    private final Serializer<String> stringSerializer = new DefaultSerializer<String>();
    private final Serializer<Integer> integerSerializer = new DefaultSerializer<Integer>();
    private BTreePersistentIndexedCache<String, Integer> cache;
    private TestFile cacheFile;

    @Before
    public void setup() {
        cacheFile = tmpDir.file("cache.bin");

    public static final Serializer<Short> SHORT_SERIALIZER = new ShortSerializer();
    public static final Serializer<Integer> INTEGER_SERIALIZER = new IntegerSerializer();
    public static final Serializer<Long> LONG_SERIALIZER = new LongSerializer();
    public static final Serializer<Float> FLOAT_SERIALIZER = new FloatSerializer();

Class <org.gradle.internal.serialize.BaseSerializerFactory$IntegerSerializer> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (BaseSerializerFactory.java:0)