Fix findbugs violations in utils

Fix findbugs violations in utils

- Naked notify
- An apparent infinite recursive loop
- Field isn't final but should be
- Boxing/unboxing to parse a primitive
- Method concatenates strings using + in a loop
- Method ignores exceptional return value
- Reliance on default encoding
- Should be a static inner clas
- Could be refactored into a static inner class
- Result of integer multiplication cast to long

Change-Id: Ie10a638f81490f9ddc1c27f651c4471168c50bd6
Signed-off-by: Tom Pantelis <tompantelis@gmail.com>