In the java programming language, what does the following mean?

Question

temp = temp - (temp > 150 ? 100 : 20 ) ;

Is there somewhere online I can get a complete list of operators?

Answer 1

Somewhere online where you can get a list...Well, normally I just use Google or a search engine to find stuff. I'm guessing Google doesn't work for you? Because look at the first two results for http://www.google.com/search?q=java+operators

? is a ternary operator. temp > 150 returns either true or false. If true, the ternary operator returns 100, otherwise 20.

Effectively, you get
if temp > 150:
temp = temp - 100
else:
temp = temp - 20

Answer 2

(temp > 150 ? 100 : 20 )
means
if temp > 150 then result=100 else result=20



temp = temp - (temp > 150 ? 100 : 20 )
means
temp =temp-result

Answer 3

The ternary operator is inherited from the C programming language. The value of

a ? b : c

is b if a is nonzero and c if a is zero. So your statement means if temp is greater than 150, subtract 100 from it, else subtract 20 from it.

Answer 4

here is a good site for operator terminology
http://www.cafeaulait.org/course/week2/03.html

http://java.about.com/od/beginningjava/l/aa_operator_1.htm

the statement (temp > 150 ? 100 : 20 )
is equivalant to:

if temp > 150 then
temp=temp-100
else
temp=temp-20
end if

Answer 5

A full list of operators can be found here