Logical and Relational Operation Session 5

2. Logical and Relational OperationSession 5 Course : T0974 Algorithm & Object-Oriented Programming I Year : 2011

3. Learning Outcomes After taking this course, student should be expected to apply and demonstrate using Relational and comparator operator, Logical operator and bitwise operator.

4. Lecture outline • Relational & Comparator procedure • Relational & Comparator operator • Logic & Boolean procedure • Logic & Boolean operator • Truth table • Bitwise Operation

5. Relational procedure • Relational procedure == Comparator procedure. • Comparing two values. • Using 6 relational/comparator operator. • The result has Boolean type. • The values have number, ASCII, or String data type.

6. Comparator operator

7. Comparator operator • Character can be compared by refering to its ASCII number. • Example: ‘a’ is more bigger than ‘A’ because ASCII number for ‘a’ (97) is bigger than ASCII number for ‘A’ (65). • Word can be compared by String helper. • Comparator operator is different than asssignment operator. X = 14  store 14 to X. X == 14  compare if X is equal to 14.

8. Comparator Operation

9. Logic/Boolean Procedure • Logical procedure == Boolean procedure. • Execute 1 or 2 logic values. • It has 4 types Logic/Boolean operator. • The result has Boolean data type. • Truth table

10. Boolean Operator

11. NOT (!) • Operator not (!) inverts the original value. • true  false and false  true

12. AND (&&) • AND Operator (&&) is true when all of its operands are true. • If one of its operand is false, then AND is false.

13. OR (||) • OR (||) Operator is true if one of every its operand is true. • If all of its operands become false then OR is false.

14. XOR (^) • Operator XOR (^) is true when both if its operands has different condition. • When its operands has same condition then XOR is false.

15. Tabel Kebenaran: Demo

16. Thruth Table: Demo

17. Thruth table: Leap Year

18. Did You Know? • When evaluating p1&&p2, Java evaluates p1 first. • If p1 is true then Java evaluates p2. • If p2 is false then Java doesn’t evaluate p2. • When evaluating p1||p2, Java evaluates p1 first • If p1 is true then Java doesn’t evaluate p2. • If p1 is false then Java evaluates p2.

19. Advanced Learning • Bit : the smallest unit in data. • 1 byte = 8 bits. • 1 bit has 0 or 1. • Java support bitwise operator to do bit shift. • Example : 0000 0000  0 0000 1000  8 0000 0001  1 0001 0000  16 0000 0010  2 0010 0000  32 0000 0011  3 0100 1101  77 0000 0100  4 1111 1111  255

20. Advanced Learning • Bit’s values is same as boolean • 1 : true • 0 : false • Its procedure is same as logical procedure. &  && (AND) |  || (OR) ^  ^ (XOR) ~  ! (NOT/NEGATE) • Additional operator << : shift left (unsigned) >> : shift right (signed) >>> : shift right (unsigned)

21. Advanced Learning

22. Advanced Learning • Shorthand for bitwise operation : &=, |=, ^=, <<=, >>=, >>>= • Bitwise only can be used for real number like : byte, short, int and long. • Bitwise for Char type converts to int which refer to ASCII number.

23. Advanced Learning

24. Advanced Learning

25. References • Introduction to Java Programming. 8ed. Liang. 2011. p96-97 • Dasar Pemrograman Java 2. Abdul Kadir. 2004. p76-83 • The Complete Reference Java. 5ed. Herbert Schildt. 2005. p62-76 • Java 2 Weekend Crash Course. Julio Sanchez. 2002. p85-96 • Bitwise: • http://java.sun.com/docs/books/tutorial/java/nutsandbolts/op3.html • http://www.sap-img.com/java/java-bitwise-logical-operators.htm • http://www.leepoint.net/notes-java/data/expressions/bitops.html • http://www.javabeginner.com/java-operators.htm