Can I dynamically create a Java object in the run time via JSON?

Question

For example, I have a JSON format like this:

{"class":"MySpecialClass", "attri1":"value1", "attri2":"value2"}

I would like to create a Object, which is a MySpecialClass Object, and get two attribute, attri1 and attri2 with the value of value1 and value2.

Here is the requirement:

I have a class file, named, MySpecialClass, and have attri1, and attri2, can I create this object, and assign the value in this?
I DONT'T have the class file MySpecialClass, I would like to generate it on the runtime, is this possible to do so? Thanks.

Possible duplicate of http://stackoverflow.com/questions/1395551/convert-a-json-string-to-object-in-java — Zéychin, Aug 03 '12 at 08:48

score 3 · Accepted Answer · answered Aug 03 '12 at 08:49

Your first case is perfectly feasible using any Java/JSON parser.

Your second case is possible, but hard work.

You can construct classes at runtime using bytecode engineering - e.g. using Apache BCEL. Note that the JSON will contail fields only, and not behaviour nor type.

score 1 · Answer 2 · edited Feb 16 '20 at 11:05

1

Take a look at https://github.com/google/gson it does what you want

edited Feb 16 '20 at 11:05

Cœur

37,241
25
195
267

answered Aug 03 '12 at 08:48

fmsf

36,317
49
147
195

score 0 · Answer 3 · answered Aug 03 '12 at 08:48

You want a JSON processor, like Jackson. I'm not sure you can easily do your second case this way, for that you may be best looking at a JVM JavaScript implementation unless you want to get into stuff like on the fly bytecode manipulation. There's one in the Java6 runtime.

Can I dynamically create a Java object in the run time via JSON?

3 Answers3

Linked