Transcript 619 Final Review

332 Final Review
Fall 2015
Professor Ammann
Agenda
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Review Technical Topics Covered
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Identify Areas for Study on Final
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Final May Test Several Concepts at Once
Thursday, December 17 @ 10:30
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Key Facets of Object Orientation
Final is NOT at noon!!!
Length: 2 hours and 30 minutes (max)
Goal: Strong Showing on Final
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Exceptions
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How to program Java exceptions
Rationale for exceptions
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Providing defined behavior
Bloch Items 57-65
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Exceptions for exceptional conditions
Checked vs. unchecked exceptions
Standard exceptions
Matching exceptions to the abstraction
Failure Atomicity
Ignoring Exceptions
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JUnit and JavaDoc
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JUnit tests for a given JavaDoc description
JavaDoc and JUnit for exceptions
Contract model and Junit
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JUnit theories
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(typed) parameters in test methods
Data sources (JUnit)
preconditions: assumeTrue(…)
postconditions: assertTrue(…)
Can you count?
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Contracts
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Fundamental Topic
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Expect Significant Exam Coverage
Understanding, not Formality, is the Focus
Method contracts
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Preconditions, Postconditions, Invariants
Relation to JavaDoc
Relation to JUnit
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Data Abstraction
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Abstraction Functions
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Representation Invariants
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What they are
How to implement (toString())
What they are
How to check
Fair exam questions
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Identify abstract states wrt implementation states
Identify states that satisfy/violate rep invariants
Identify rep invariants that disallow certain states
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Method Verification
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Verification of methods in isolation
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Two part verification
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Maintain representation invariant
Show implementation satisfies contract
Role of the abstraction function
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Representation invariant captures method
interactions
Relating implementation state to abstract state
Fair exam question
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Given contract/code pair
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Will verification succeed? If not, why not?
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Object Creation/Destruction
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Rules for Object creation
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Bloch Chapter 2
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Constructor chaining and it’s analogues
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Static factories, constructors with many parameters
Similar rules apply for cloning, serialization
Access to uninitialized state
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See Bloch Item 17
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Substitution Principle
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Core principle for inheritance
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Nuances of “IS-A” relationship
Reasoning About Subtypes
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Signature Rule
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Methods Rule
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Rules for Exceptions
Preconditions/Postconditions
More Rules for Exceptions
Relation to Method Verification
Properties Rule
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Substitution Principle and
Methods Common to All Objects
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Understand the problem
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equals()
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hashCode()
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Transitivity, Symmetry, Substitution for subtypes
Consistency with equals()
Understand the solution
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Composition (Bloch Item 16)
Understand Bloch’s InstrumentedSet example
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Iteration Abstraction
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What’s the state of a given iterator?
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How do preconditions figure into Java
iterators?
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With next(), hasNext()?
With remove()?
With previous(), hasPrevious()?
Can they be transformed into exceptions?
Good exam question:
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How does the state evolve as the iterator is
used?
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Polymorphic Abstraction
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Element Subtype vs. Related Subtype
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Comparable vs. Comparator
Addable vs Adder
Good exam question:
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Analyze/Repair a defective Comparator
implementation
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What, exactly, does “defective” mean?
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Mutability
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Key topic
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Should be comfortable converting between
mutable and immutable types
Achieving mutability, using guidance from
both Liskov and Bloch
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Transforming mutators to producers
Limiting subtyping
Limiting changes to instance variables
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Generics
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Programming with Java generics
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Understand that they are really “ungenerics”
Type safety aspects
Java Generics (Bloch Chapter 5)
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Arrays vs. Lists
Converting to generics
What do bounded wildcards do?
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? extends E
? super E
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Enums and Annotations
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Problems with C-Style Enums
Enums, EnumSet, EnumMap
Simple Annotations
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@Test, @SuppressWarnings, @Override…
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Odds and Ends
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Basic Agile
Basic Usable Security
Just having been in class should be
enough here
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Wrap Up
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Closed Book/Notes/Slides/Phone/Web/etc.
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You may bring one (1) 8.5”x11” paper
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Bring something to write with
Your handwriting – no printing/photocopying
Double-sided is fine
Goal: Effective study aid
Prepare with quizzes, in-class exercises
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At least one quiz or in-class will be on final
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More Wrap Up
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Grading issues (Blackboard) must be
brought to my attention by the final exam
Questions?
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