PythonJavaRepository

Code to achieve json normalization in Java via python

What this code does?

• This is a sample code to perform json normalization in java with the help of python.

Why I have written this code?

• We had a requirement where input json needs to be normalized inorder to be written to db.
• No utility for this requirement is available in Java out of box and we end up writting very messy custom code.
• Found that this utility is readily availble in python via pandas module.So no need of 're-inventing the wheel' again. Hence written a java wrapper over python to achieve it.

What is 'normalization' by the way and what do pandas do?

• Well please go through following link for a clear explanation:

  http://pandas.pydata.org/pandas-docs/version/0.17.0/generated/pandas.io.json.json_normalize.html

Sound coool, well how to run this?

• Please find steps below to run the same.

• Please refer http://pandas.pydata.org/pandas-docs/version/0.17.0/generated/pandas.io.json.json_normalize.html to model your input json data.

• I have used the same example explanied in the above link to run the code.

• First and formost, we you are a java developer, its time to show some love to python2. Please install python2 and pandas module to run this program.

• Following are the arguments and orders to be passed to this java program : arg[0] = path to python executable arg[1] = path to python script file arg[2] = input json file arg[3] = record path arg[4] = meta

  Last three arguments needs to be formatted a bit, inorder to make it ready for python to execute it as command line arguments. For example :

  In order to run this program please give the following String as arguments to this java program:

  "--path to python executable OR env_variable name--"

  "--path to python file to be executed--"

  ""[{""state"":""Florida"",""shortname"":""FL"",""info"":{""governor"":""RickScott""},""counties"":[{""name"":""Dade"",""population"":12345},{""name"":""Broward"",""population"":40000},{""name"":""PalmBeach"",""population"":60000}]},{""state"":""Ohio"",""shortname"":""OH"",""info"":{""governor"":""JohnKasich""},""counties"":[{""name"":""Summit"",""population"":1234},{""name"":""Cuyahoga"",""population"":1337}]}]""

  ""counties""

  ""[""state"", ""shortname"",[""info"", ""governor""]]""

Where is the python script by the way?

• You may find a simple py script file named "normalization.py" in source code.

So whats next?

• Please check this if it fits into your requirements and let me know for issues or bugs.

Happy coding and have a nice day.