Junit assertThat compare JsonObject

Question

I am a beginner in junit I would like to test two JsonObject with dynamic data especially the date.

I have a proprety "CreationDate", In the first json I use the localDateTime "now()" on the other hand the jsonTest file contains a literal date.

JsonObject actual = (JsonObject) parser.parse(myListResponse.readEntity(String.class));
JsonObject expected = (JsonObject) parser.parse(fixture("path/jsonTest.json"));
    
assertThat(actual , is(expected));

How I can resolve this to get a valid test

Answer 1

You have to create a custom Matcher by extending BaseMatcher. Then you can do the comparison/matching by using the desired fields. For example:

static class JsonObjectMatcher extends BaseMatcher<JsonObject> {
    private final JsonObject target;

    public static JsonObjectMatcher customMatchesTheJson(final JsonObject expected) {
        return new JsonObjectMatcher(expected);
    }

    private JsonObjectMatcher(JsonObject target) {
        this.target = target;
    }

    @Override
    public boolean matches(Object o) {
        if (o instanceof JsonObject) {
            final JsonObject other = (JsonObject) o;
            // TODO: 5/11/21 Custom compare target to other
        }
        return false;
    }

    @Override
    public void describeTo(Description description) {
        // TODO: 5/11/21 Add to the description
    }
}

And you can use it to match as follows:

assertThat(actual, JsonObjectMatcher.customMatchesTheJson(expected));