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How to use import java.util.regex.Pattern ?

somkiat puisungnoen
Ranch Hand

Joined: Jul 04, 2003
Posts: 1312


Result for complied above code

java.util.regex.PatternSyntaxException: Dangling meta character '*' near index 0
*welcome*
^
at java.util.regex.Pattern.error(Pattern.java:1528)
at java.util.regex.Pattern.sequence(Pattern.java:1645)
at java.util.regex.Pattern.expr(Pattern.java:1545)
at java.util.regex.Pattern.compile(Pattern.java:1279)
at java.util.regex.Pattern.<init>(Pattern.java:1035)
at java.util.regex.Pattern.compile(Pattern.java:779)
at com.spns.history.TestPattern.main(TestPattern.java:21)
Exception in thread "main"


Why i don't use "*" in pattern?

--------
p.s. When i remove "*" is work fine.


SCJA,SCJP,SCWCD,SCBCD,SCEA I
Java Developer, Thailand
Amit Ghai
Ranch Hand

Joined: Mar 24, 2004
Posts: 35
The '*' character by itself does not mean anything in regular expressions. If it follows a character, character class, or group, then it means 'zero or more' of the thing it follows.

If your intention with "*welcome" is "zero or more of any character, welcome" then the expression you want is: ".*welcome";
The '.' character will match any character, and the '*' works as stated above.


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subject: How to use import java.util.regex.Pattern ?