I'm trying to manually update a bean (it is an argument to a JAX-RS resource method). The value of the field to be set in the bean is to be deserialized from JSON, contextually.
I want to do:
ObjectMapper objectMapper = new ObjectMapper();
// .... <configured, ClassIntrospector obtained for type> ...
BeanProperty prop;
// ... <bean property resolved through ClassIntrospector> ...
AnnotatedMember mutator = prop.getMutator();
JsonFactory jf = new JsonFactory();
JsonParser parser = jf.createParser(textProp);
Object value = objectMapper.getDeserializationContext().readValue(parser, mutator.getRawType());
mutator.setValue(beanInstance, value);
The problem is that Jackson is throwing a NullPointerException:
at com.fasterxml.jackson.databind.DeserializationContext.getTypeFactory(DeserializationContext.java:251)
at com.fasterxml.jackson.databind.DeserializationContext.readValue(DeserializationContext.java:758)
I confirmed with the debugger that the _config field of my DeserializationContext is null, and that this is what is being accessed during my code sequence.
So, what gives? How can I configure this properly so that this works? (Or is there some other way to manually deserialize a JSON fragment to a given type, respecting the JAX-RS resource context / classes?)
Related
I have to deserialize a Class in third-party jar that contains a Map<String,Object> Collection property, so that the Annotation #JsonDeserialize cannot be used to defined at the property level,
I find that ObjectMapper can be registered with the custom deserializer, like
ObjectMapper mapper = new ObjectMapper();
SimpleModule module = new SimpleModule();
module.addDeserializer(X.class, new XDeserializer());
mapper.registerModule(module);
X x = mapper.readValue(json, X.class);
but this is for class, is there any way to register a custom deserializer for property?
I found that the annotation #Cacheable cannot work when the method returns a Java Bean type, this is the complete description:
I annotated #Cacheable on a method to use spring cache:
#Cacheable(cacheNames="userCache", key="#userId")
public User getUser(long userId){
return userRepository.getUserById(userId);
}
And the User class like this:
public class User{
Long userId;
String username;
#JsonSerialize(using = LocalDateTimeSerializer.class)
#JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
private LocalDateTime birthDateTime;
}
As you can see, I annotated the relating Jackson annotations to make Jackson deserialization for LocalDateTime types work, and this is the related dependency in pom.xml:
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jsr310</artifactId>
<version>2.12.5</version>
</dependency>
After that, I call the #Cacheable method getUser like this:
User user = userCache.getUser(1L);
and there throws an exception:
org.redisson.client.RedisException: Unexpected exception while processing command
at org.redisson.command.CommandAsyncService.convertException(CommandAsyncService.java:326)
at org.redisson.command.CommandAsyncService.get(CommandAsyncService.java:123)
at org.redisson.RedissonObject.get(RedissonObject.java:82)
...blabla
Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Java 8 date/time type java.time.LocalDateTime not supported by default: add Module "com.fasterxml.jackson.datatype:jackson-datatype-jsr310" to enable handling at [Source: (io.netty.buffer.ByteBufInputStream); line: 1, column: 101] (through reference chain: com.stackoverflow.domain.User["birthDateTime"]) at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)
at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1764)
at com.fasterxml.jackson.databind.deser.impl.UnsupportedTypeDeserializer.deserialize(UnsupportedTypeDeserializer.java:36)
at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
3.Before I use the #Cacheable, there is no problem if I get the User from database straightly. But when I begin to use #Cacheable, it always throws the exception above, no matter if I configured those Jackson deserialization for LocalDateTime. Is #Cacheable cannot work well with Java Bean with LocalDateTime property, or just my configuration of Jackson is wrong?
I had the same problem. Spring Cache doesn't use the implicit ObjectMapper used by other Spring components.
Include the module, you already did that.
Create a configuration which will override the default Spring Cache Configuration:
#Configuration
#EnableCaching
public class CacheConfiguration {
#Bean
public RedisSerializationContext.SerializationPair<Object> serializationPair() {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.registerModule(new JavaTimeModule())
.activateDefaultTyping(
objectMapper.getPolymorphicTypeValidator(),
ObjectMapper.DefaultTyping.EVERYTHING,
JsonTypeInfo.As.PROPERTY
);
return RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer(objectMapper));
}
#Bean
public RedisCacheConfiguration redisCacheConfiguration(
#Value("${cache.default-ttl-in-seconds}") Integer ttl,
RedisSerializationContext.SerializationPair<Object> serializationPair
) {
return RedisCacheConfiguration.defaultCacheConfig()
.disableCachingNullValues()
.entryTtl(Duration.ofSeconds(ttl))
.serializeValuesWith(serializationPair);
}
}
I'm currently using Jersey and Moxy in Glassfish 4. Is there a way to tell Jersey/Moxy to refuse a HTTP request if its JSON content is not valid (i.e. it contains more objects than it should when binding JSON to a POJO) ?
I would create my own subclass of MOXyJsonProvider (see: http://blog.bdoughan.com/2012/05/moxy-as-your-jax-rs-json-provider.html). Then in that subclass I would override the preReadFrom method. In that method I would set an Unmarshaller.Listener.
#Override
protected void preReadFrom(Class<Object> type, Type genericType,
Annotation[] annotations, MediaType mediaType,
MultivaluedMap<String, String> httpHeaders,
Unmarshaller unmarshaller) throws JAXBException {
Unmarshaller.Listener ul = new YourUnmarshallerListener();
unmarshaller.setListener(ul);
}
Then Unmarshaller.Listener would then count each time an object was unmarshalled and error out if too many are read.
public class Model {
}
public class SuperclassDTO {
private boolean funny = true;
public boolean isFunny() {
return funny;
}
public boolean setFunny(boolean f) {
this.funny = f;
}
}
public class SubclassDTO extends SuperclassDTO {
}
new SubclassDTO().isFunny() //returns true
SubclassDTO dto = binder.bindFromBusinessObject(SubclassDTO.class, new Model());
dto.isFunny(); //returns false!!!!
Isn't this weird? Model class does not have a "funny" field but somehow dto is bind with a wrong value. First I thought jDTO required "getFunny" convention, so it couldn't read the value and just set it "false" but changing the getter name to "getFunny" does not resolve the issue, plus I'm not allowed to modify SuperclassDTO. How can I bind the correct value?
Jdto version 1.4 by the way...
The behavior you're experiencing is a "side effect" of the convention over configuration approach. All the fields on the DTO are configured unless you mark them as transient, either by using the #DTOTransient annotation or the transient configuration on the XML file. If a configured field does not have a corresponding field on the source bean, it will be set with default values and that is the reason why you're experiencing this behavior.
You have some options to overcome this issue:
Add the #DTOTransient annotation to the DTO.
Since you're not able to modify the DTO, you could configure it through XML.
Use Binding lifecycle to Restore the value. By adding code on the subclass.
You might as well submit a bug report on the jDTO issue tracker on github.
I am using Spring Integration to consume a message with a JSON Payload.
In my spring context I have
<integration:channel id="jsonToMyMessageConverterChannel"/>
<integration:json-to-object-transformer
type="com.acme.messaging.message.MyMessage"
input-channel="jsonToMyMessageConverterChannel"
output-channel="myMessageUpdateChannel"/>
My message related objects are:
MyMessage.java
#JsonIgnoreProperties(ignoreUnknown=true)
public class MyMessage {
#JsonProperty
private String timestamp;
#JsonProperty("msgs")
private List<Message> messages;
// Getters and Setters...
}
Message.java
#JsonIgnoreProperties(ignoreUnknown=true)
public class Message {
#JsonProperty
private Integer msgId;
#JsonProperty("msgText")
private String text;
// Getters and Setters...
}
When the json transformer attempts to convert the message to an object it fails with
Caused by: org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "msgs" (Class com.acme.messaging.message.MyMessage), not marked as ignorable
The JSON payload definitely has msgs which is an array that has objects which represent the Message.java class.
Can any one suggest reasons why the exception occurs given that the JSON has the field that is being complained about and the class itself is also annotated to ignore unknown fields?
Update
After some debugging it looks like the #JsonProperty("msgs") annotations aren't being use, for some reason.
This works fine for me...
#Test
public void test() throws Exception {
MyMessages mm = new MyMessages();
MyMessage m = new MyMessage();
m.setMsgId(1);
m.setText("foo");
mm.setMessages(Arrays.asList(m));
mm.setTimestamp("123");
#SuppressWarnings("deprecation")
ObjectToJsonTransformer otjt = new ObjectToJsonTransformer(new ObjectMapper());
Message<?> message = new GenericMessage<MyMessages>(mm);
message = otjt.transform(message);
System.out.println(message);
#SuppressWarnings("deprecation")
JsonToObjectTransformer<MyMessages> jtot = new JsonToObjectTransformer<MyMessages>(MyMessages.class, new ObjectMapper());
message = jtot.transform(message);
mm = (MyMessages) message.getPayload();
System.out.println(mm.getTimestamp());
System.out.println(mm.getMessages().get(0).getText());
}
(I changed your classnames slightly to avoid colliding with Message<?>)
Resulting in...
[Payload={"timestamp":"123","msgs":[{"msgId":1,"msgText":"foo"}]}][Headers={timestamp=1373997151738, id=f2425f36-a500-4aee-93a4-e7e0240ce0f1, content-type=application/json}]
123
foo
Do you have both jackson 1.x (codehaus) and 2.x (fasterxml) on the classpath, and using Spring Integration 3.0.0?
If they're both on the classpath, SI will use Jackson 2.x, by default, (which won't understand 1.x annotations).
Or, I guess - are you using Jackson2 (fasterxml) annotations? Spring Integration 2.x uses Jackson 1 (codehaus).
EDIT:
In order to support both versions of Jackson, you can annotate the class with both annotations...
#JsonProperty("msgs")
#com.fasterxml.jackson.annotation.JsonProperty("msgs")
public List<MyMessage> messages;