New Tag request: java-ee-8
It's got a new feature, called jsonb. With jsonb, I cannot get nested serialization working. See bold printed below.
So, I wrote a jaxrs-application. This application's got a messagebodywriter using jsonb:
final JsonbConfig defaultConfig = new JsonbConfig()
.withFormatting(Boolean.TRUE)
.withNullValues(Boolean.TRUE)
.withSerializers(
new QueryParamEntrySerializer(),
new ApiResponseDtoSerializer())
.withAdapters(new ResponseStatusJsonbAdapter());
final Jsonb jsonb = JsonbBuilder.create(defaultConfig);
ApiResponseDto is like following:
@Value.Immutable
@JsonbTypeSerializer(ApiResponseDtoSerializer.class)
public interface ApiResponseDto {
ResponseStatus status();
String message();
Optional<? extends Object> data();
}
ResponseStatus is an enumm and gets serialized via the above TypeAdapter just fine. For this class I wrote the ApiResponseDtoSerializer.
@Provider
public class ApiResponseDtoSerializer implements JsonbSerializer<ImmutableApiResponseDto> {
@Override
public void serialize(
final ImmutableApiResponseDto obj,
final JsonGenerator generator,
final SerializationContext ctx) {
generator.writeStartObject();
ctx.serialize("status", obj.status(), generator);
ctx.serialize("data", obj.data(), generator);
ctx.serialize("message", obj.message(), generator);
generator.writeEnd();
}
}
Now the Optional data() shall contain an ImmutableSet of QueryParamEntry like this:
@Value.Immutable
@JsonbTypeSerializer(ImmutableQueryParamEntrySerializer.class)
public interface QueryParamEntry {
@Value.Parameter
String key();
@Value.Parameter
Optional<String> value();
}
The type adapter is this one:
@Provider
public class ImmutableQueryParamEntrySerializer implements JsonbSerializer<ImmutableQueryParamEntry> {
private static final Logger LOG = LoggerFactory.getLogger(ImmutableQueryParamEntrySerializer.class);
@Override
public void serialize(
final ImmutableQueryParamEntry obj,
final JsonGenerator generator,
final SerializationContext ctx) {
generator.writeStartObject();
LOG.debug("Writing: key = [{}].", obj.key());
ctx.serialize("key", obj.key(), generator);
ctx.serialize("value", obj.value(), generator);
generator.writeEnd();
}
}
The final output is:
{
"status": "success",
"data": [
{
"key": null,
"value": null
}
],
"message": "Returning query param values."
}
As you can see, the nested serialization did not work. Jsonb seems to find the correct type (because otherwise it wouldn't serialize an object at all). But even the log statement from my SerializerClass is never called.
Btw: You need Guava 22 and immutables.github.io to compile this code, and slf4j obviously:
<dependency>
<groupId>org.jboss.resteasy</groupId>
<artifactId>jaxrs-api</artifactId>
<version>3.0.2.Final</version>
<scope>provided</scope>
</dependency>
<!-- JSON-P API -->
<dependency>
<groupId>javax.json</groupId>
<artifactId>javax.json-api</artifactId>
<version>1.1</version>
<scope>provided</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.json.bind/javax.json.bind-api -->
<dependency>
<groupId>javax.json.bind</groupId>
<artifactId>javax.json.bind-api</artifactId>
<version>1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.immutables</groupId>
<artifactId>value</artifactId>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
</dependency>
