Java：此正则表达式有什么问题？

Question

I am trying to get the text inside a tag ie <text> . I am doing:

Pattern pattern = Pattern.compile("(?<=\\<).*(?=\\>)");

I think that this says: any character 0 or more times that before is a < (positive lookbehind) and followed by > (positive lookahead).

Matcher m = pattern.matcher(data);  
if (!m.matches()) continue; //Called in a for loop  

But there is no match for eg the input <text> some other stuff here .

What am I doing wrong here?

Answer 1

When you are using matches() , the entire input string must match the expression. If you want to find substrings, you may use find() instead.

Answer 2

Don't use m.matches() but m.find() .

From the JavaDoc on matches() :

Attempts to match the entire region against the pattern.

Answer 3

You can try this to match:

public static void main(String[] args) {
    String input = "<text> Some Value </text> <a>  <testTag>";
    Pattern p = Pattern.compile("<(\\w.*?)>");
    Matcher m = p.matcher(input);

    while(m.find()){
       System.out.println(m.group(1));
    }
}

Answer 4

I don't quite understand your regular expression, but this works for me:

String text = "<text>";
Pattern p = Pattern.compile(".*<(.*)>.*");
Matcher m = p.matcher(text);
System.out.println(m.matches());
System.out.println(m.group(1));

this displays:

true
text

Is that what you need?