regex problem: 'greater than' 'less than' and 'equals' not matching!

[falcon]

I have a very strange problem. I want to replace every thing in a
string except letters, numbers, space, and certain symbols listed in
the regex expression below

"blahblah !@#$%^&*()--.,<>=".replaceAll("[^A-Za-z0-9/-?).,'+^| ]","")

I expect to get the following string back:
"blahblah ^().,"

but I actually get the following:
"blahblah ^().,<>="

Notice the greater/less than and equals signs are still there!

I did a quick check using this site:
http://www.fileformat.info/tool/regex.htm and I get the same result
back. What's going on here???

 

[colirl]

Hi,

I have not actually run the regex with my fixes but first of all there
are a few problems. Characters like $, |, [, ), \, / and so on are
peculiar cases in regular expressions. If you want to match for one of
those then you have to preceed it by a backslash. So:

\| # Vertical bar
\[ # An open square bracket
\) # A closing parenthesis
\* # An asterisk
\^ # A carat symbol
\/ # A slash
\\ # A backslash

Try this for your ( and ) and see if it makes any difference! I dont'
have the time to test the fix but thats what you need to do for special
charachters.

 

[falcon]

colirl,
That doesn't seem to work. Besides, it is replacing most of right
characters with blanks, for some reason it keeps relational symbols
(><=).

 

[falcon]

Sorry, it does work, I had to move some chars in my regext string
around, but adding back slashes to those characters which have special
meaning apparently was the problem. Thanks colirl!

 

[colirl]

Ok you need to escape the - symbol because as I said, specail
characters need to be escaped.

try [^A-Za-z0-9/\-?).,'+^| ] as your expression. gets rid of
the ><= for me.

 

[colirl]

so then you get


blahblah ^()--.,


Solution:
"blahblah !@#$%^&*()--.,<>=".replaceAll("[^A-Za-z0-9/\-?).,'+^|
]","")


Enjoy

 

[Jussi Piitulainen]

I have a very strange problem. I want to replace every thing in a
string except letters, numbers, space, and certain symbols listed in
the regex expression below

"blahblah !@#$%^&*()--.,<>=".replaceAll("[^A-Za-z0-9/-?).,'+^| ]","")

/-? contains :;<=>.

 

[falcon]

Jussi,
I already fixed the problem, but its amusing that I missed seeing /-?
as *from '/'* *to '?'*

Thanks

 

[Rob Skedgell]

Ok you need to escape the - symbol because as I said, specail
characters need to be escaped.

try [^A-Za-z0-9/\-?).,'+^| ] as your expression. gets rid of
the ><= for me.

Or you can put a '-' unescaped as the last character in a character
class, since it doesn't form part of a range e.g. "[a-z-]" will match
"-". Admittedly the 1.5.0 javadocs for java.util.regex.Pattern at
<http://java.sun.com/j2se/1.5.0/docs/api/java/util/regex/Pattern.html#cc>
don't make that clear: "inside a character class ... the expression -
becomes a range forming metacharacter."

 

[colirl]

Rob,
ya, I had forgotten about that one. .

 

[Roedy Green]

Sorry, it does work, I had to move some chars in my regext string
around, but adding back slashes to those characters which have special
meaning apparently was the problem. Thanks colirl!

It its pretty hairy since \ is used both by regex and string literals
for quoting. so a literal \ becomes \\\\
see http://mindprod.com/jgloss\regex.html#QUOTING