I found this question on how to port PHP's preg_match to Java (it recommends using String.matches(). However, I still have trouble with the following situation:
PHP:
preg_match('/<(h1|h2|h3|h4|ul|td|div|table)/i', '<h1>') => returns 1
Java:
"<h1>".matches("/<(h1|h2|h3|h4|ul|td|div|table)/i") => return false
Why would that be?
In Java, matches() requires a full string match. And you do not need regex delimiters.
"<h1>".matches("(?i)<(h1|h2|h3|h4|ul|td|div|table)>")
See IDEONE demo
If you plan to use the same regex in Java, use Matcher with find() (find will match anywhere in the input string and Pattern.CASE_INSENSITIVE will act as i option in PHP):
String str = "<h1>";
String rx = "<(h1|h2|h3|h4|ul|td|div|table)";
Pattern ptrn = Pattern.compile(rx, Pattern.CASE_INSENSITIVE);
Matcher m = ptrn.matcher(str);
while (m.find()) {
System.out.println(m.group(0));
}
See another demo
Patter.compile thing?
import java.util.regex.*; import.You need to remove the regex delimiters.
And also you need to add (?i) modifier for doing case-insensitive match.
Finally you have tyo add > at the last since matches method tries to match the whole string.
"<h1>".matches("(?i)<(h1|h2|h3|h4|ul|td|div|table)>");
<h1>hello</h1>, java version wouldn't
Pattern and Matcher classes.In Java it should be:
"<h1>".matches("(?i)<(h[1234]|ul|td|div|table)>");
i.e. no regex delimiter and (?i) for ignore-case comparison.
