Lecture 11

1. COP3502: Introduction to CIS I Lecture 11

2. anatomy of a class <modifier> class <class name> { // instance variables <modifiers> <type> <name>; // constructor <modifier> <class name> ( <arguments> ) { <constructor body> } // methods <modifiers> <return type> <function name> ( <arguments> ) { <function body> } }

3. anatomy of instance variables public class Complex { // instance variables //<modifiers> <type> <name>; publicdouble real; publicdoubleimag; ... … … }

4. anatomy of a constructor publicclass Complex { … … // constructor //<modifier> <class name> ( <arguments> ) publicComplex(intr, inti ) { real = r; imag = i; } … … }

5. anatomy of a constructor public class Complex { … … // constructor //<modifier> <class name> ( <arguments> ) public Complex(intr, inti ) { real = r; imag = i; } … … } Complexcnum = new Complex(8,6);

6. anatomy of a method public class Complex { … … // methods //<modifiers> <return type> <function name> ( <arguments> ) publicComplexadd(Complexn) { Complex sum = new Complex(real * n.real, imag * n.imag); return sum; } … … }

7. packages collection of tools written by other programmers that perform specific operations

8. packages collection of tools written by other programmers that perform specific operations accessed using import keyword

9. packages collection of tools written by other programmers that perform specific operations accessed using import keyword import java.awt.Color;

10. Point p = new Point(3,4); OR Point p; p = new Point(3,4)

11. memory 1 byte = 8 bits

12. intnum; num 32 bits = 4 bytes

13. intnum; num = 400; binary - 110010000 num 32 bits = 4 bytes

14. objects

15. Complex n; n

16. Complex n; n = new Complex(3,4); n “reference”

17. Complex n1 = new Complex(8,6); Complex n2 = new Complex(3,5); n2 n1

18. Complex n; n = new Complex(8,6); “This is not a pipe” “n is not a Complex”

19. wrapper classes