/**
    * Logback: the reliable, generic, fast and flexible logging framework.
    * Copyright (C) 1999-2011, QOS.ch. All rights reserved.
    *
    * This program and the accompanying materials are dual-licensed under
    * either the terms of the Eclipse Public License v1.0 as published by
    * the Eclipse Foundation
    *
    *   or (per the licensee's choosing)
   *
   * under the terms of the GNU Lesser General Public License version 2.1
   * as published by the Free Software Foundation.
   */
  package ch.qos.logback.core.pattern;
  
  import java.util.List;
  import java.util.regex.Pattern;
  
  public class ReplacingCompositeConverter<E> extends CompositeConverter<E> {
  
    Pattern pattern;
    String regex;
    String replacement;
  
    public void start() {
      final List<String> optionList = getOptionList();
      if (optionList == null) {
        addError("at least two options are expected whereas you have declared none");
        return;
      }
  
      int numOpts = optionList.size();
  
      if (numOpts < 2) {
        addError("at least two options are expected whereas you have declared only " + numOpts + "as [" + optionList + "]");
        return;
      }
      regex = optionList.get(0);
      pattern = Pattern.compile(regex);
      replacement = optionList.get(1);
      super.start();
    }
  
    @Override
    String transform(String in) {
      if (!started)
        return in;
      return pattern.matcher(in).replaceAll(replacement);
    }
  }