I'm trying to access a certain part of multiple strings that follow a pattern.
Here's an example of what I'm trying to do.
String s = "Hello my name is Joe";
if(Pattern.matches(s,"Hello my name is ([\\w]*)"))
{
System.out.println("Name entered: $1");
}
However, my code never enters inside the "if-statement"
Swap the parameters to the matches method, and your if will work (regex is the 1st parameter, not the second).
However, you still won't print the first capturing group with $1. To do so:
String s = "Hello my name is Joe";
Matcher m = Pattern.compile("Hello my name is ([\\w]*)").matcher(s);
if(m.matches())
{
System.out.println("Name entered: " + m.group(1));
}
I think that you are looking for this:
final String s = "Hello my name is Joe";
final Pattern p = Pattern.compile("Hello my name is (\\w++)");
final Matcher m = p.matcher(s);
if (m.matches()) {
System.out.printf("Name entered: %s\n", m.group(1));
}
This will capture the \w++ group value, only if p matches the entire content of the String. I've replaced \w* with \w++ to exclude zero length matches and eliminate backtracks.
For further reference take a look at The Java Tutorial > Essential Classes - Lesson: Regular Expressions.
Try using the Matcher class, see this page for more information about Regular Expressions in Java http://java.sun.com/developer/technicalArticles/releases/1.4regex/
Because you have the parameters to Pattern.matches() backwards.
http://docs.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html
Also, you don't need a set (the brackets). In addition, You are going to need to use the Matcher class and get the brackreference via the group() method.
ifline is missing a closing parenthesis...