Changing names of properties while Serializing to JSON without source code

问题

Need to serialize java objects to JSON while doing compression such as name change, exclusion etc. Objects use class from jar, source code of which is not available.

Looked through many libraries(Jackson , Gson), but found none solving this particular problem. Most of them are annotations based, which I can't use given I don't have source code.

One way to solve this problems is, use reflection and recursively go through object until you find a property name of which should be replaced or object is excluded in serialized JSON.

Need solution for this. Better if it is already implemented and tested.

回答1:

You can also have a look at Genson library http://code.google.com/p/genson/.

You can rename and filter with quite concise code:

// renames all "fieldOfName" to "toName", excludes from serialization 
// and deserialization fields named "fieldNamed" and declared in DefinedInClass
// and uses fields with all visibility (protected, private, etc)

Genson genson = new Genson.Builder().rename("fieldOfName", "toName")
                                    .exclude("fieldNamed", DefinedInClass.class)
                                    .setFieldFilter(VisibilityFilter.ALL)
                                    .create();

genson.serialize(myObject);

If you want to do some more complex filtering (based on annotations for example) you can implement BeanMutatorAccessorResolver or extend BaseResolver.
Same for property renaming you can implement PropertyNameResolver and have full control.
And finally if you want to filter fields, methods or constructors according to their modifiers you can define your own VisiblityFilter.
Concerning performances of filtering/renaming there should be no problem as it is done only once per class and then cached.

To start using Genson you can have a look at the Getting Started Guide.

回答2:

Found solution to the problem.

Google gson has class called GsonBuilder which has methods for exclusion strategy and naming strategy.

Using these two methods implemented a custom solution, where all the mapping and exclusion rules are stored using a xml and used at the time of serialization and de-serialization.

Works perfectly, though not sure about the performance of same.

来源：https://stackoverflow.com/questions/12619991/changing-names-of-properties-while-serializing-to-json-without-source-code

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java

json

serialization