Java – Search for a regexp in a java arraylist

arraylistjavaregexsearch

ArrayList <String> list = new ArrayList(); 
list.add("behold");
list.add("bend");
list.add("bet");
list.add("bear");
list.add("beat");
list.add("become");
list.add("begin");

There is a way to search for the regexp bea.* and get the indexes like in ArrayList.indexOf ?

EDIT: returning the items is fine but I need something with more performance than a Linear search

Best Solution

Herms got the basics right. If you want the Strings and not the indexes then you can improve by using the Java 5 foreach loop:

import java.util.regex.Pattern;
import java.util.ListIterator;
import java.util.ArrayList;

/**
 * Finds the index of all entries in the list that matches the regex
 * @param list The list of strings to check
 * @param regex The regular expression to use
 * @return list containing the indexes of all matching entries
 */
List<String> getMatchingStrings(List<String> list, String regex) {

  ArrayList<String> matches = new ArrayList<String>();

  Pattern p = Pattern.compile(regex);

  for (String s:list) {
    if (p.matcher(s).matches()) {
      matches.add(s);
    }
  }

  return matches
}

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