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Finally! Google opened up the AppInventor to the general public.

This SQL Snippet get a list of all the tables under a user:

select * from user_objects where object_type = 'TABLE';

This SQL Snippet will get you a list of all the sequences in a DB Schema for the user tables

select * from user_sequences

This SQL Snippet will get you a list of all the view in a DB Schema for the user tables

select * from user_views;

Happy Coding :)

In order to remove any null pointer exceptions while using RestEasy Annotations, you can always pass a default value and handle it appropriately in the Data Access Objects ( If you are using one. This ensures that there are no null pointer excpetions from the returning classes.

Here is a code snippet to do just this:

public StreamingOutput getUsersSummaryList(@QueryParam("active") @DefaultValue("0") String active  ){}

If you ever come across a PerGen space error in Hibernate or JPA...it refers to the java.lang.outfspacememoryerror (Your webapp is out of memory). PermGen is  used to store the class definations ( and I do mean all the Loaded Classes ). This error refers to the heap space being full due to the large number of classes.

Generally you can recover from these errors by restarting your WebServer. If you want to really fix it, do one of the following 2:

1. Hibernate: Change the hibernate.properties file from  "hibernate.bytecode.provider javassist" to hibernate.bytecode.provider cglib".

2. JPA:  Change the persistance.xml file from <property name="hibernate.bytecode.provider" value="javaassist"/> to <property name="hibernate.bytecode.provider" value="cglib"/>

Happy Coding :)

For the regular J2EE/Java programmers that use the amazing Tomcat as their Servlet container, i found an amazing link. It steps through the necessary configurations to debug your servlets....an awesome find :)

http://wiki.apache.org/tomcat/FAQ/Developing

Share what you learn...and Happy Coding :)