Transcript java -agentlib:hprof Prog

Object-Oriented Design
Object Oriented Design
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CRC stands for Classes, Responsibilities,
Collaborators
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Class name goes on the top
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Responsibilities go on the left
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Collaborators go on the right
UML Basics
Inherits, is a...
Implements, is a...
Aggregation, has a...
Dependency
Design
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Identify nouns
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Group nouns into packages
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Responsibilities
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Identify more nouns & responsibilities
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Use case - example that helps identify what the
program needs to do/handle
Testing
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It's a good idea to write unit tests, small
examples of things that should happen
Language feature: assert()
Documentation
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/** javadoc comment */
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put them on classes, methods, fields, as
appropriate
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@see refer to another class or method
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@param document a param
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@return document the return value
Examples
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Blackjack?
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Chess?
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Battleship?
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Adventure?
Debugging
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To debug:
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compile with the -g flag, javac -g Prog.java
To run the debugger
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local debugging
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jdb Prog
remote debugging
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java -Xdebug Xrunjdwp:transport=dt_socket,server=y,address=8080 Prog
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jdb -attach 8080
To profile:
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run like this: java -agentlib:hprof Prog
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then start jconsole and attach to your program
Debugging
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stop at BlackJackViewer:58
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clear BlackJackViewer:58
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clears breakpoint
dump bj / print bj.game.deck.cards.size()
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sets breakpoint
prints out variables
run / step / step up / next / cont
Debugging
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threads / thread
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locals
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set
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watch
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threads
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where