Java regex to extract text between tags
To be quite honest, regular expressions are not the best idea for this type of parsing. The regular expression you posted will probably work great for simple cases, but if things get more complex you are going to have huge problems (same reason why you cant reliably parse HTML with regular expressions). I know you probably don't want to hear this, I know I didn't when I asked the same type of questions, but string parsing became WAY more reliable for me after I stopped trying to use regular expressions for everything.
jTopas is an AWESOME tokenizer that makes it quite easy to write parsers by hand (I STRONGLY suggest jtopas over the standard java scanner/etc.. libraries). If you want to see jtopas in action, here are some parsers I wrote using jTopas to parse this type of file
If you are parsing XML files, you should be using an xml parser library. Dont do it youself unless you are just doing it for fun, there are plently of proven options out there
Try this:
Pattern p = Pattern.compile(?<=\\<(any_tag)\\>)(\\s*.*\\s*)(?=\\<\\/(any_tag)\\>);
Matcher m = p.matcher(anyString);
For example:
String str = "<TR> <TD>1Q Ene</TD> <TD>3.08%</TD> </TR>";
Pattern p = Pattern.compile("(?<=\\<TD\\>)(\\s*.*\\s*)(?=\\<\\/TD\\>)");
Matcher m = p.matcher(str);
while(m.find()){
Log.e("Regex"," Regex result: " + m.group())
}
Output:
10 Ene
3.08%
You're on the right track. Now you just need to extract the desired group, as follows:
final Pattern pattern = Pattern.compile("<tag>(.+?)</tag>", Pattern.DOTALL);
final Matcher matcher = pattern.matcher("<tag>String I want to extract</tag>");
matcher.find();
System.out.println(matcher.group(1)); // Prints String I want to extract
If you want to extract multiple hits, try this:
public static void main(String[] args) {
final String str = "<tag>apple</tag><b>hello</b><tag>orange</tag><tag>pear</tag>";
System.out.println(Arrays.toString(getTagValues(str).toArray())); // Prints [apple, orange, pear]
}
private static final Pattern TAG_REGEX = Pattern.compile("<tag>(.+?)</tag>", Pattern.DOTALL);
private static List<String> getTagValues(final String str) {
final List<String> tagValues = new ArrayList<String>();
final Matcher matcher = TAG_REGEX.matcher(str);
while (matcher.find()) {
tagValues.add(matcher.group(1));
}
return tagValues;
}
However, I agree that regular expressions are not the best answer here. I'd use XPath to find elements I'm interested in. See The Java XPath API for more info.
A generic,simpler and a bit primitive approach to find tag, attribute and value
Pattern pattern = Pattern.compile("<(\\w+)( +.+)*>((.*))</\\1>");
System.out.println(pattern.matcher("<asd> TEST</asd>").find());
System.out.println(pattern.matcher("<asd TEST</asd>").find());
System.out.println(pattern.matcher("<asd attr='3'> TEST</asd>").find());
System.out.println(pattern.matcher("<asd> <x>TEST<x>asd>").find());
System.out.println("-------");
Matcher matcher = pattern.matcher("<as x> TEST</as>");
if (matcher.find()) {
for (int i = 0; i <= matcher.groupCount(); i++) {
System.out.println(i + ":" + matcher.group(i));
}
}