io.camunda.zeebe.protocol.jackson.AnnotationIntrospector Maven / Gradle / Ivy
/*
* Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH under
* one or more contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright ownership.
* Licensed under the Zeebe Community License 1.1. You may not use this file
* except in compliance with the Zeebe Community License 1.1.
*/
package io.camunda.zeebe.protocol.jackson;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties.Value;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.introspect.Annotated;
import com.fasterxml.jackson.databind.introspect.AnnotatedClass;
import com.fasterxml.jackson.databind.introspect.NopAnnotationIntrospector;
import io.camunda.zeebe.protocol.record.ImmutableProtocol;
/**
* A generic annotation introspector for the protocol's immutable concrete types.
*
* Immutable classes, having no default or public constructor, don't work nicely with Jackson out
* of the box. However, we can simulate the {@link
* com.fasterxml.jackson.databind.annotation.JsonPOJOBuilder} annotation on these classes by adding
* an annotation introspector which will find the inner {@code Builder} class and return it, as if
* the class had been annotated with {@link JsonDeserialize}.
*
*
Additionally, for forwards-compatibility reasons, we ignore unknown properties for all
* immutable protocol types.
*
*
By default, we only introspect types annotated with the marker {@link ImmutableProtocol.Type}
* or {@link ImmutableProtocol.Builder} annotations.
*/
final class AnnotationIntrospector extends NopAnnotationIntrospector {
@Override
public Value findPropertyIgnoralByName(final MapperConfig config, final Annotated ann) {
if (ann.hasAnnotation(ImmutableProtocol.Type.class)
|| ann.hasAnnotation(ImmutableProtocol.Builder.class)) {
return JsonIgnoreProperties.Value.forIgnoreUnknown(true);
}
return super.findPropertyIgnoralByName(config, ann);
}
@Override
public Class findPOJOBuilder(final AnnotatedClass ac) {
// find builder for abstract type, e.g. Record, TimerRecordValue, etc.
final ImmutableProtocol annotation = ac.getAnnotation(ImmutableProtocol.class);
if (annotation != null) {
return annotation.builder();
}
// find builder for concrete type, e.g. ImmutableRecord, ImmutableTimerRecordValue, etc.
final ImmutableProtocol.Type type = ac.getAnnotation(ImmutableProtocol.Type.class);
if (type != null && type.builder() != null) {
return type.builder();
}
return super.findPOJOBuilder(ac);
}
}