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cs205: engineering software
university of virginia fall 2006
Introducing
Java
David Evans
www.cs.virginia.edu/cs205
Don’t forget to email your registration survey –
if you haven’t yet, please do it today
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cs205: engineering software
Course Announcements
• Assistant Coaches:
Drew Abott and Dan Marcus
– Lab hours: after class today, Sunday 7-
8:30pm
• Office Hours
– Posted time conflicts with cs202
– New time is 10:30-noon on Thursdays
– My door is almost always open – feel free
to stop by outside of office hours
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cs205: engineering software
Why so many
programming languages?
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cs205: engineering software
Fundamental Differences
• All equivalently powerful!
–Universal languages: all capable of simulating
each other
• Fundamental differences
– Expressiveness: how easy it is to describe a
computation
– “Truthiness”: likelihood that a program means
what a programmer things it means
– Safeness: impact of programmer mistakes
• There is usually a conflict between
expressiveness and truthiness/safeness
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cs205: engineering software
Pragmatic Differences
• Performance of available compilers,
interpreters
• Tools available
• Libraries
• Portability
• Availability/cost of programmers
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cs205: engineering software
What is Java?
A. Island in Indonesia known for coffee
and volcanoes
B. A Programming Language (Java)
C. A Portable Low-Level Language (JVML)
D. A Platform (JavaVM)
E. A (semi-)successful marketing strategy
– JavaScript is not related to Java or Java
F. All of the above
