Final Review

1
Final Review
2
Final Details

• Monday, December 11th
• 700pm 1000pm
• HCC 1325

3
Sections Covered - Detailed View

• 1.1-1.2, 1.4-1.6
• 2.1-2.6
• 3.1-3.3, 3.6-3.8 covered 3.4, 3.5 in class
• 4.1-4.4 covered 4.5 in class
• 5.1-5.5, 5.7-5.8 (basically) covered 5.6 in
  class
• 6.1-6.5, 6.7, 6.8 covered 6.9 in class
• 7.1-7.2, 7.6-7.7 covered 7.4 in class
• 8.1-8.5
• 9.1-9.5
• 10.1-10.6
• 11.1-11.3
• some parts of 12 covered in class notes

4
Sections Covered - Broadly

• Chapters 1-11
• (except for Graphics track)
• with minor exceptions

5
Other Topics (from before midterm)

• Running time / Big O notation
• Working with references handout
• including null/this
• Merge sort
• Command line arguments
• printf

6
Other Topics (after midterm)

• More detailed treatment of some topics
• polymorphism (e.g. covered Collections)
• file output (e.g. covered buffers and generic
  Writers)
• File input
• Call Stack
• Scanning tokens
• Regular Expressions

7
Chapter 1

• Computer processing
• The Java Programming Language
• Program Development
• Object-Oriented Programming
• (very basic)

8
Chapter 2

• Character Strings
• Variables and Assignment
• Primitive Data Types
• Expressions
• Data Conversion
• Interactive Programs

9
Chapter 3

• Creating Objects
• The String Class
• Packages
• Formatting Output
• (plus more detailed coverage of printf)
• Enumerated Types
• Wrapper Classes

10
Chapter 4

• Anatomy of a Class
• Encapsulation
• Anatomy of a Method

11
Chapter 5

• The if Statement and Conditions
• Other Conditional Statements
• Comparing Data
• The while Statement
• Other Repetition Statements

12
Chapter 6

• Software Development Activities
• Identifying Classes and Objects
• Static Variables and Methods
• Class Relationships
• Interfaces
• Method Design
• Testing
• (covered the same material in class)

13
Chapter 7

• Declaring and Using Arrays
• Two-Dimensional Arrays
• The ArrayList Class

14
Chapter 8

• Creating subclasses
• Overriding methods
• Class hierarchies
• Inheritance and visibility
• Designing for inheritance

15
Chapter 9

• Polymorphism
• polymorphic references
• through inheritance
• through interfaces
• Searching
• linear search
• binary search
• Sorting
• insertion sort
• selection sort
• merge sort

16
Chapter 10

• Exception Handling
• The try-catch Statement
• Exception Classes
• I/O Exceptions

17
Chapter 11

• Recursive Thinking
• Recursive Programming
• Using Recursion

18
Running Time Big-O

• For a parameter n
• e.g. the length of a string or size of an array
• count the number of steps performed
• loop through n elements n steps
• loop inside a loop n2 steps
• Ignore constants coefficients
• 3n 2 steps O(n)
• n2 /2 steps O(n2)
• cutting problem in half at each step O(log n)

19
Working with References

• null reference
• Object variable not assigned anything
• When does this cause an exception?
• this reference
• When does this simplify code?

20
File I/O

• Where do the exceptions happen?
• How do we handle them?
• Why do we want to buffer?
• How do we buffer?
• Using Scanner
• with default tokens
• with defined tokens

21
Regular Expressions

• Given regular expression
• yes/no matching questions
• give informal description
• Given informal description
• write regular expression
• pass appropriately to Scanner

22
What Kind of Questions?

• Look at the exercises in the text
• finding errors in code
• finding differences in code
• explaining/defining concepts
• predicting output of code
• writing methods or classes
• specifying/justifying design from requirements

23
What Kind of Questions?

• Similar format for lecture material
• e.g. specify running time
• e.g. find null reference problem
• Using regular expressions
• Predicting tokens parsed
• Describe call stack
• including exceptions
• explain stack trace

24
It May Be on the Test if

• It is in the text
• It is in the lecture notes
• It is something I said in class or wrote on the
  blackboard
• It was part of a lab/assignment

25
What Code Do You Need to Know?

• Officially everything as per previous slide
• Unofficially
• I try to only assume you know important methods
  and classes
• but I decide what is important
• in general little used methods that occur rarely
  in the notes will be given implicitly
• but you should know enough code to solve problems
  without help/look-up

26
Examples

• There will be definitions (again)
• abstract class
• checked exception
• final method
• overridden method

27
Examples

• There may be explanations required
• Explain why a static method cannot refer to an
  instance variable.
• Give two differences between an abstract class
  and an interface.

28
Examples

• Draw a UML diagram for a single class hierarchy
  representing these animals, with abstract classes
  grouping animal types
• parrot
• gorilla
• horse
• bat
• penguin
• Add an interface for flyers

29
Examples

• Correct the problems
• Flyer polly new Parrot()
• Animal koko new Gorilla()
• Gorilla junior koko.makeOffspring()
• polly.layEgg()

30
Examples

• Define appropriate classes and public methods for
  the given requirements.
• Every salesperson will be assigned a unique ID
  number, and a numbered office with a phone.
  Salespeople will sell vacuum cleaners at a fixed
  price. When inventory runs out, the top
  salesperson will be designated employee of the
  month.

31
Examples

• Find the exception in this code, and handle it.
• public static void main(String args)
• FileWriter fileout new FileWriter(names.txt)
  
• if(fileout!null)
• fileout.write(John Smith)
• else
• System.out.println(No name written to file)

32
Examples

• Find the exception in this code, and handle it.
• public static void main(String args)
• Student s new Student(4533453,tsmith)
• String fname s.getFirstName()
• System.out.println(fname)

33
Examples

• Given this information in file.txt
• 7 5 5p , 4
• Write the code that will print these tokens to
  the screen using a Scanner/delimiter
• 7 5 5 and , 4
• 7 and and p , 4

34
Solution

• Scanner filein new Scanner(
• new File(file.txt)
• ).useDelimiter(p)
• while(filein.hasNext())
• System.out.println(filein.next())

5
35
Examples

• Yes or no expression matching
• 1-7a? 43
• (17)(17a)? 17a
• abcdef(di)? bed
• 123(45)?a 12312345aaaa
• abbccde abcde
• A-CDEF? ABCDE
• truck.stop trstopstop

yes
no
no
yes
yes
no
yes
36
Examples

• Describe the strings matching the expressions
• (cat)
• catcat
• cat?
• ca?t
• (c?a)t?
• c-ta?c-t

37
Examples

• What is the value in variable temp after
• int temp 30
• String stemp temp 12
• temp temp Integer.parseInt(stemp)
• Again
• CollectionltIntegergt l new ArrayListltInteg
  ergt
• int temp 40
• l.add(40)
• temp l.size()

38
Examples

• Write a method that picks a random character in
  the string string.

39
Examples

• What is wrong with this?
• How can it be corrected?
• int count1,max0
• while(countmax)
• System.out.println(count)
• count-2

40
Examples

• A LinkedList implements Collection
• Write a method that adds every word in the
  sentence This is a sentence to a LinkedList,
  then prints the size.

41
Examples

• Given double input, write a method that returns
  the highest value

42
Examples

• Write a class NamedArrayList that extends
  ArrayList by adding a name for the array list in
  the first position.

43
Examples

• What is wrong with these declarations
• char chars d, a, b
• String new String5
• Scanner sc new Scanner(5)

44
Examples

• Write a recursive function that returns true if
  the input is a power of 3.
• Write a recursive function that returns true if a
  string contains only the letter s.