Read and write Json properties using methods (ie. getters & setters)

[GoogleCodeExporter]

if your object has an int getId(); method. Maybe you want to have a 

@Field("id")
public int getId();

When the Json is generated the getId() method is called and the result is 
placed in "id"
I know that I could have a int field in my class, but, in my case the Id is 
generate by Hibernate once the object is saved.

Original issue reported on code.google.com by Germanattanasio on 7 Sep 2010 at 2:04

[jansohn]

This would be very helpful when working with JavaFX properties, e.g. javafx.beans.property.StringProperty, as these properties cannot be instantiated with an empty constructor.

[schlm3]

GSon is useless for me without this feature. Wanted to use it for client server communication together with a GWT app while using a common Data interface. The point is, that the server already has it's very own object model and likes only to provide a view for the json serialisation which should look like the data required inside the GWT app. Would have worked perfectly if gson had supported getter/setter like serialisation.

[rajsrivastav1919]

I have the same requirement, I want Gson to use setters for setting the field instead of reflection.
I am deserializing a thrift object's json (which does not contain isSet vector details). If setter methods were called, isSet vector will be formed automatically.
(It can be argued that isSet vector should have been present in the json in the first place. Agreed, but it is an internal field for use by thrift and thrift takes the pain of maintaining it every time some fields are edited.)

With current Gson implementation, thrift objects can't be deserialized "effectively". Other JSON & XML deserializing libraries (like Jackson, CastorXML) call setters, and hence the objects formed are compatible with thrift. For now, I am using Gson by making changes in it for calling setter methods instead of using reflection.

From the thread above, I see that you don't want to give native support in Gson for this feature.
My suggestion is to add a flag in GsonBuilder which indicates Gson to use getter/setter methods. This will be set to false by default so the current functionality does not change. If set to true, Gson will try to call getter/setter methods if present, otherwise fallback to reflection for getting/setting the values. This will make Gson compatible to be used for Thrift objects also.

For 99% POJO classes current implementation works I agree. But, having as an optional feature shouldn't harm anyone I guess.

[inder123]

@rajsrivastav1919 Would be great for someone to fork Gson with support for this. As we understand the solution better, we will consider adding it.

[rajsrivastav1919]

Thanks @inder123 for the consideration. I will try to point out some genuine use cases for this if I find any.

Meanwhile, here is how I have been using it till now in various projects in my company. If you have some suggestions regarding the approach, I'll be glad to incorporate them.

[tobilarscheid]

Hi, let me add to this and outline our teams desired use case for this feature:

We came to use gson as the couchdb java driver uses gson. Every POJO you want to store is serialized by gson. What we would like to do is add a generic interface that contains the standard fields (i.e. their getters) that every object in our db needs (Think revision, last updated, stuff like this). Unfortunately this is not possible with gson not being able to serialize based on getter/setter methods.