Teach Yourself Java in 21 Days

Week 3 at a Glance
303
Day
15
Modifiers
305
Method and Variable Access Control ...................................................... 307
The Four P’s of Protection ................................................................. 307
The Conventions for Instance Variable Access ................................... 312
Class Variables and Methods .................................................................. 314
The final Modifier .................................................................................. 316
final Classes ....................................................................................... 316
final Variables .................................................................................... 317
final Methods .................................................................................... 317
abstract Methods and Classes .................................................................. 319
Summary ................................................................................................ 320
Q&A ...................................................................................................... 320
Day
16
Packages and Interfaces
323
Packages ................................................................................................. 324
Programming in the Large ................................................................. 324
Programming in the Small ................................................................. 327
Hiding Classes ................................................................................... 329
Interfaces ................................................................................................ 331
Programming in the Large ................................................................. 331
Programming in the Small ................................................................. 335
Summary ................................................................................................ 338
Q&A ...................................................................................................... 339