No validating saxparser implementation available

The DVM crashed with an error saying “parent class loader may not be null”. Composite Class Loader, I found the constructor that was the culprit. Thanks to Kris, this was a quick fix for me, to replace super(null) call by super(Composite Class Loader.Class Loader()).

no validating saxparser implementation available-58

In other words, if the user-specified is set, it must receive those errors, and if not, they must be treated according to the implementation specific default error handling rules.

A validator may modify the SAX event stream (for example by adding default values that were missing in documents), and a parser is responsible to make sure that the application will receive those modified event stream. Note that "the validation" here means a validating parser as defined in the XML recommendation.

At this time I had spent reasonable amount of time getting this option “A” to work, So I decided to start following my plan “B”.

Here I serialized my knowledge base and wrote it to a file.

The assumption was fare and simple, I needed to run a java app on a platform that supports java. Option “B” appeared to be more suitable for a “mobile” type environment, at least at this initial stage, but option “A” was better from application/rule upgrade standpoint, so I started with option “A”. ) exercise I learnt a lot of good android stuff which proved to be very useful in later part of this journey– how to root an android device, adb tools, pushing and pulling files to and from the device, packaging application and so on.

After getting a basic Hello World android app built using Eclipse and Android SDK, I pushed it out to my android device and boom! Later, upgrading the app to use SQLlite database wasn’t a huge deal.

Getting Drools to work on Android, wasn’t as easy as it appeared initially.

My thought ( which was later found to be too optimistic to be true ) was that Drools is java based and android supports java, so just port drools library and application to Android and run the application. “A” – to compile and load rules at run time on android and “B” – to pre-compile the rules and package the precompiled/serialized rules and de-serialize and load on android.

The next challenge was to do something that was never done before or very few folks out there have tried, was to get Drools to work on a mobile platform.

Since Android’s getting very popular these days and since it has good java support ( and of-course I had recently bought a new Android phone ), Android was the mobile platform of choice !

This led to another discovery that Android’s java is not sun’s java, but it is the Google implementation of java.

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