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#Transient variable is not serialized using jackson [duplicate]

We use JSON serialization with Jackson to expose internal state of the system for debugging properties.
By default jackson does not serialize transient fields - but I wish to serialize them as well.
How can I serialize these fields?
One way I know is to supply a getters for these fields - but I don't want to do that, as I have some getX methods that I don't want to be invoked ( for instance, there are some getters that change the objects state ).
I know I could create an annotation, but I really want to avoid it.
So my question is:
Is there a way to setup jackson to serialize all the objects fields? include transient ones.

My solution with Jackson 2.4.3:
private static final ObjectMapper mapper =
new ObjectMapper(){{
Hibernate4Module module = new Hibernate4Module();
module.disable(Hibernate4Module.Feature.USE_TRANSIENT_ANNOTATION);
registerModule(module);
}};

I don't think Jackson supports any type of configuration to enable it to serialize a transient field. There's an open issue to add that feature, but it's old and hasn't been addressed (as far as I can tell): http://jira.codehaus.org/browse/JACKSON-623
So my question is: Is there a way to setup jackson to serialize all
the objects fields? include transient ones.
So to answer your question, no.
Some other Java JSON tools, such as GSON do support a configuration option to serialize transient fields. If you can use another tool, you might look into that (for GSON, see: https://sites.google.com/site/gson/gson-user-guide).
To expand a little, you might try a different approach.
First, You shouldn't try to serialize a transient field. After all the definition of transient is "don't serialize this." Nevertheless I can think of a few specific situations where it might be necessary, or at least convenient (like when working with code you can't modify or such). Still, in 99% of cases, the answer is don't do that. Change the field so that it's not transient if you need to serialize it. If you have multiple contexts where you use the same field, and you want it serialized in one (JSON, for example), and not serialized in another (java.io, for example) then you should create a custom serializer for the case where you don't want it, rather than abuse the keyword.
Second, as to using a getter and having "some getters that change the objects state," you should try to avoid that too. That can lead to various unintended consequences. And, technically, that's not a getter, that's a setter. What I mean is, if it mutates state, you've got a mutator (setter) rather than accessor (getter), even if you name it following the "get" convention and return some stuff.

You can create a custom getter for that transient field and use #XmlElement attribute. It doesn´t matter the name of that getter.
For example:
public class Person {
#XmlTransient private String lastname;
#XmlElement(name="lastname")
public String getAnyNameOfMethod(){
return lastname;
}
}

Another way to let Jackson serialize property is to add #JsonProperty annotation above it.
I guess it's better approach cause you do not need to disable default behaviour for all #Transient fields, like in Gere's answer.

Is is possible to create a combo-annotation which combines multiple field annotations?

I have some boolean fields in my JPA entities which are annotated in the following way:
#Column(length = 1)
#Type(type = "yes_no")
private final boolean myField;
Is it possible to create a combo-annotation (e. g. MyAnnotation) which combines both of this annotations?
#MyAnnotation
private final boolean myField;
How?

Obviously you could create an annotation that provides the equivalent of multiple other annotations.
Equally obviously no JPA provider will support it, since they will check for the javax.persistence annotations only (not that #Type is javax.persistence).

What you want is similar to CDI stereotypes - unfortunately, JPA does not support such a concept, therefore you must copy recurring annotations all over.
If you can afford to wrap your field into an object, you may mark it as #Embeddable and put your field into it - the annotations on that field will be copied wherever you embed that object into an entity. You may extend the annotations using #AnnotationOverrides. Obviously, the drawback of such solution is additional complexity when accessing the field in your entity.

Ignore #Transient fields of an entity automatically during json serialization

I am using hibernate for entity persistance in application along with spring mvc I have a multiple #Transient fields in an entity in a application is there a way to tell Json parser to automatically ignore all #Transient annotated fields in entity without the need to use #JsonIgnore or #JsonIgnoreProperties

#Transient is to indicate the field is not persistent. #JsonIgnore is to indicate the field is to be ignored by the serialization/deserialization processor, they have very different meanings.
One option is have Json processor base serial/deserialization from available fields (vs getter/setters), then mark your #Transient fields with additional transient keyword. If you have getters/setters, you'll also need to add appropriate visibility rules. For example, this will serialize all fields not marked with transient.
#JsonAutoDetect(fieldVisibility=Visibility.ANY, getterVisibility=Visibility.NONE, setterVisibility = Visibility.NONE)

I have found a better way instead of using #jsonignore to the fields in an entity
on child class use JsonBackreference and on parent use JsonManagedReference
For more information go through this blog post

Jackson deserialization specific getter turning off

What is the most simple way to tell the Jackson to not serialize a specific getter method? I only want to say explicit to one getter, because I have a custom, complex class, and all setter and getter should function, only one should not:
mapper.configure(SerializationConfig.Feature.AUTO_DETECT_GETTERS, true);
So this is not the proper way. I need to tell that I don't want to use the getter in this class:
public static class EventRow implements Serializable, Cloneable, GRSerializable {
public int x
public int y
public double z
public String eventKeyValuesPacked;
//This getter should not be used, because there is no explicit setter
//for this, and also no public... And it is only unpack
//EventKeyValuesPacked so it would be multiple data...
public KeyValue[] getEventKeyValues() {
KeyValue[] kvs = DA_EventKey.unpackKeyValues(eventKeyValuesPacked);
return kvs == null ? new KeyValue[0] : kvs;
}
}
Is there any annotation or SerializationConfig option to make invisible the getEventKeyValues() getter method?

What is the most simple way to tell the Jackson to not serialize a specific getter method
...
without annotation?
Without writing a customer serializer...
If directly annotating the field/property/getter/setter to be skipped is undesirable, another approach is to make use of the Jackson Mix-In feature.
Yet another approach for serialization only would be to make use of the Jackson JSON Views feature, though this too requires annotations in some capacity.

There is an annotation for this: #JsonIgnore.
#JsonIgnore
public KeyValue[] getEventKeyValues() {
...
If you don't want to use an annotation for this then you'll need to write a custom serializer.

I think this almost do it:
objectMapper.configure(DeserializationConfig.FAIL_ON_UNKNOWN_PROPERTIES,
false);

This may depend on Jackson version -- prior to 1.9, getters and setters were handled separately, so not auto-detecting getter would have been enough. But with 1.9 and beyond, setter/getter/field are all combined into logical property, which may allow Jackson to deduce existence of property from setter.
So what you probably need to do is to also disable setter detection. Other options already given would work as well, mix-in annotations being a common way to do this.

objectMapper.configure(SerializationConfig.Feature.AUTO_DETECT_GETTERS, false);

Omitting one Setter/Getter in Lombok

I want to use a data class in Lombok. Since it has about a dozen fields, I annotated it with #Data in order to generate all the setters and getter. However there is one special field for which I don't want to the accessors to be implemented.
How does Lombok omit this field?

You can pass an access level to the #Getter and #Setter annotations. This is useful to make getters or setters protected or private. It can also be used to override the default.
With #Data, you have public access to the accessors by default. You can now use the special access level NONE to completely omit the accessor, like this:
#Getter(AccessLevel.NONE)
#Setter(AccessLevel.NONE)
private int mySecret;

According to #Data description you can use:
All generated getters and setters will be public. To override the
access level, annotate the field or class with an explicit #Setter
and/or #Getter annotation. You can also use this annotation (by
combining it with AccessLevel.NONE) to suppress generating a getter
and/or setter altogether.