Quantifiers and Greedy Quantifiers

Hello Ranchers,
Is there any difference between Quantifiers and greedy quantifiers OR are all quantifiers Greedy Quantifiers?

Sorry if its too basic question but iam literally confused.

Thanks
Prashanth

I presume you're referring to regular expressions. There is a difference: there are non-greedy quantifiers such as "??", "*?" and "+?", in contrast to greedy quantifiers like "?", "*" and "+". According to K&B, only greedy quantifiers are examined in SCJP 5.

What are the differences among greedy, reluctant and possessive quantifiers?

Thanks for the URLs.
Also iam getting bit scared as my exam is within 2 weeks away and i have read some basics

..Anyways i will give it a go.I dont have much time.I have allocated only 1 month for the exam.So fingers crossed.I hope i pass the exam;-);-)

Cheers
Prashanth

Hello,
I have again got this confusion..
How can i ever find out when is a quantifier becomes greedy
ex:
1)proj([^,])* --> is a quantifier

2).*xx --> is a greedy quantifier

can anyone advice?

Thanks

Did you write the text at that link yourself Wise?

How can i ever find out when is a quantifier becomes greedy

A qualifier, by default, is greedy. When you see the qualifier followed by a "?", then it is declared as reluctant.

In both of your examples, neither "*" qualifier is followed by a "?".

Henry

Originally posted by Henry Wong:

In both of your examples, neither "*" qualifier is followed by a "?".

Henry

So according to it,given the following text
"proj3.txt,proj1sched.pdf,proj1,proj2,proj1.java"

and pattern

proj1([^,])*

why doesnt it match the whole text..It acts as a reluctant and matches

proj1sched.pdf
proj1
proj1.java

Many Thanks
Prashanth

So according to it,given the following text
"proj3.txt,proj1sched.pdf,proj1,proj2,proj1.java"

and pattern

proj1([^,])*

why doesnt it match the whole text..It acts as a reluctant and matches

proj1sched.pdf
proj1
proj1.java

Just because the regex doesn't match the "whole text" doesn't make the qualifier "reluctant". In this case, the "greedy" qualifier still has to obey what is being qualified ([^,]) and can't match anything with commas.

If you change the qualifier in the pattern to reluctant:

proj1([^,])*?

You will see that each find() will try to match as little as possible. And the matches are...

proj1
proj1
proj1

Hope this helps,
Henry

Did you write the text at that link yourself Wise?

Originally posted by Marcus Green:
Did you write the text at that link yourself Wise?

Not unless his real name is Anant Athale.

Quoting from xyzws.com:

The XyzWS.com is hosted by a group of hardworking Renjings who call themselves the Tigons.

Indeed.