Get Found regex : String Operation « Regular Expressions « Java

Get Found regex

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import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Utils {
  public static List<String> getFound(String contents, String regex) {
      if (isEmpty(regex) || isEmpty(contents)) {
          return null;
      List<String> results = new ArrayList<String>();
      Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CASE);
      Matcher matcher = pattern.matcher(contents);
      while (matcher.find()) {
          if (matcher.groupCount() > 0) {
          } else {
      return results;

  public static boolean isEmpty(String str) {
      if (str != null && str.trim().length() > 0) {
          return false;
      return true;


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