* Define beans for handling different message types in a lean chat app
* Add class based spring beans configuration
* Define spring configuration in XML for constructor based bean injection
* Refactor package structure to separate constructor based bean injection code set from setter based bean injection code set
* Define configuration and classes specific to setter-based bean injection.
* Implement tests for constructor-based and setter-based bean injections
* develop codes for explaining type erasure
* Write unit tests for type erasure examples
* Remove evaluation article code
* Modify type erasure examples and unit tests
* Modify type erasure examples and unit tests
* Add expected exception in TypeErasureUnitTest
* Correct grammar in class name
* Implement File Manager app to demonstrate Polymorphism. Develop unit tests for Polymorphism article code
* Add examples for static polymorphism
* Change sysout statments to slf4j log info statements
* Add assertions and expected errors check on Test
* Add assertions and expected errors check on Test
* Correct compile time error of symbol not found
* Removed commented out non-compiling test.
* move security content from spring-security-rest-full
* swagger update
* move query language to new module
* rename spring-security-rest-full to spring-rest-full
* group persistence modules
* group testing modules
* try fix conflict
* cleanup
* group and cleanup
* add readme to grouping modules
* move spring-jpa to persistence-modules
* minor fix
* move security content from spring-security-rest-full
* swagger update
* move query language to new module
* rename spring-security-rest-full to spring-rest-full
* group persistence modules
* group testing modules
* try fix conflict
* cleanup
* group and cleanup
* add readme to grouping modules
* move spring-jpa to persistence-modules
