org.json.simple.JSONObject VS org.json.JSONObject , JSONException cannot be resolved to a type
org.json and org.json.simple are two different Java libraries, which are incompatible with each other. The fact that they have the same name is only a misleading coincidence.
To compare the two libraries:
General comparison = http://www.rojotek.com/blog/2009/05/07/a-review-of-5-java-json-libraries/org.json.simple = http://code.google.com/p/json-simple/
org.json = http://json.org/java