Get First Not Empty String in a String list

  

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 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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 *
 * http://www.apache.org/licenses/LICENSE-2.0
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 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
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 */
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Utils {

  public static String getFirstNotEmpty(List<String> list) {
    if (isEmpty(list)) {
      return null;
    }
    for (String item : list) {
      if (!isEmpty(item)) {
        return item;
      }
    }
    return null;
  }

  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) {
        results.add(matcher.group(1));
      } else {
        results.add(matcher.group());
      }
    }
    return results;
  }


  public static boolean isEmpty(List<String> list) {
    if (list == null || list.size() == 0) {
      return true;
    }
    if (list.size() == 1 && isEmpty(list.get(0))) {
      return true;
    }
    return false;
  }

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

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Get First Not Empty String in a String list : String Operation « Regular Expressions « Java

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