Logback: the reliable, generic, fast and flexible logging framework.
Copyright (C) 1999-2015, 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.
/**
 * Logback: the reliable, generic, fast and flexible logging framework.
 * Copyright (C) 1999-2015, 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
    protected String transform(E event, String in) {
        if (!started)
            return in;
        return pattern.matcher(in).replaceAll(replacement);
    }
}