This document discusses Java arrays, loops, packages, access levels, encapsulation, and interfaces. It provides examples of declaring and initializing arrays of different types, accessing array elements, and multidimensional arrays. It also covers while, do-while, and for loops. Finally, it mentions packages, access levels (private, protected, public, default), final, interfaces, class casting, and persistence.

1. Day 3

2. static

3. null reference

4. Java Arrays

5. Type[] arrayName = new Type[elements count];

6. int[] array1 = new int[10]; String[] array1 = new String[10]; Object[] array1 = new Object[10]; MyType[] array1 = new MyType[10];

7. String[] colors = new String[] {“red”, “blue”, “white”};

8. How To Access Elements?

9. String[] friends = new String[10]; friends[0] = “Oleg”; friends[1] = “Alex”; friends[3] = “Irina”; System.out.println(friends[1]); System.out.println(friends[3]);

10. Multidimensional arrays

11. Type[][] arrayName = new Type[rows count][columns count];

12. Java Loops

13. while (condition) { …. }

14. do { …. } while (condition);

15. for (counter; condition; increment) { …. }

16. Goals

17. Packages

18. Access Levels (Private, Protected, Public, default)

19. Private – this class only

20. Protected – this class and children

21. Public – no limits

22. default – package private

23. Encapsulation

24. final

25. Interfaces

26. Class casting

27. Never, Never, Never, Never Give Up!