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Using Jyson to decode json documents

API compatibility with the cpython json module.

When I originally wrote jyson, I devised my own api, to make it suitable for usage both from jython and from java. However, as discussed on the wiki front page, I have decided that it is better for jyson to use the same API as the cpython json module .

Therefore, I have changed the jyson API to be closer to the cpython json module API, a process that is not yet complete . However, you can use a limited subset of the cpython API, by importing jyson like this (assuming that you have placed the jyson.jar file on your classpath)

>>> from com.xhaus.jyson import JysonCodec as json
>>> json.loads('["Hello World!"]')
['Hello World!']

Usage

To decode JSON text into jython objects, simply pass the JSON data to the loads method, like so

>>> from com.xhaus.jyson import JysonCodec as json
>>> json.loads('{"Hello":"World"}')
{'Hello': 'World'}
>>> json.loads('[1,1.1,null,"Hello World"]')
[1, 1.1, None, 'Hello World']
>>>

Strings passed to jyson must not be byte-encoded

Note that the string that is passed to the decode method must be a jython string or java.lang.String that is not byte encoded. If you wish to decode a string that is byte encoded, then you should decode it yourself first before passing it to the method. The following code illustrates

>>> from com.xhaus.jyson import JysonCodec as json
>>> utf8_json_data = '["Al\xc3\xa1in"]'
>>> decoded_json_data = utf8_json_data.decode('utf-8')
>>> decoded_json_data
u'["Al\xe1in"]'
>>> json.loads(decoded_json_data)
['Al\xe1in']
>>>

You might want to read this discussion of why jyson does not deal with character encodings.

Mappings to jython data types.

JSON documents consist of specific datatypes, which jyson maps to specific jython objects. The types to which they are mapped is described on a separate page: jyson decode mappings.

Options to control the parsing process.

Jyson can operate in either strict mode, under which all JSON documents must strictly conform to the JSON specification, or in permissive mode, under which a variety of non-conformant (but useful) syntactical constructs are accepted. These options are described on a separate page jyson decode options.

Updated by Alan Kennedy about 15 years ago ยท 3 revisions