When JSON support was added in APEX, I was one of those guys who jumped up and down. Started using heavily for one of my integration project and everything was fine and dandy for couple week. Since yesterday, I have been noticing some weired behavior. The first time I noticed it, I thought it was one of those APEX issues I love to call "APEX weirdness" and hoped that it will fix itself (READ: getting fixed without us knowing). That hasn't happened. :(

Here is the issue. 

My JSON parsing code looks like this:

class SomeApexWrapper {

public static SomeApexWrapper getInstance(String jsonString)

JSONParser parser = JSON.createParser(jsonString);       

SomeApexWrapper w = (SomeApexWrapper) parser.readValueAs(SomeApexWrapper.class);

}

}

This code was working fine until two days ago. It stops working If I change any class that uses this class to parse json string. The error I get is "[Source: java.io.StringReader@21363a13; line: 1, column: 1] Don't know the type of the Apex object to deserialize"

Just saving the SomeApexWrapper  class again fixes the issue. 

Has anyone had/having this issue? Is there a permanent solution for this?