@Test
    public void testJsonBindings() {
        var fsVolume = JsonUtil.readValue(TEST_JSON, FsVolume.class);
        Assertions.assertThat(fsVolume)
                .isNotNull();
        Assertions.assertThat(fsVolume.getVolumeState())
                .isNotNull();
    }
Use this method to diagnose why your JSON-to-POJO bindings are failing.
stroom-core-shared/src/test/java/stroom/data/impl/fs/shared/TestFsVolume.java