Various code clean up and potential bug fix
- Use annotation for servlet over configuration in
web.xml
- Remove
throws
for servlet methods that do not throws exception - Remove useless
serialVersionUID
- Add
final
keyword - Remove code useless
- Add missing javadoc
- Use
StringBuffer
append instead of concatenation - Add FIXME comment (in
Metric.java
line 153 and inTreeNode.java
36) due to potential bug - Fix
CREATE DATABASE
SQL statement syntax (IF NOT EXISTS
need to be locate before database name) in order to match what is documented in official MySQL and MariaDB documentation - Fix potential bug in
TreeNode
line 82