Learning object oriented thinking [closed]

Answer 1

There's an essay in the book "ThoughtWorks Anthology" by Jeff Bay: "Object Calisthenics" in which he gives a set of rules for designing OOP sofware:

1. Use only one level of indentation per method
2. Don't use the else keyword
3. Wrap all primitives and strings
4. Use only one dot per line
5. Don't abbreviate
6. Keep all entities small
7. Don't use any classes with more than two instance variables
8. Use first-class collections
9. Don't use any getters/setters/properties

On the first look it may look too strict to follow all these rules. Keep in mind that even trying to write some code that coplies them will make you better OOP designer.