slf4j-migrator/src/main/java/org/slf4j/migrator/line/MultiGroupConversionRule.java

/**
 * Copyright (c) 2004-2011 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */
package org.slf4j.migrator.line;

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

/**
 * This class represents a conversion rule It uses a Pattern and defines for
 * each capturing group of this Pattern a replacement text
 * 
 * @author jean-noelcharpin
 * 
 */
public class MultiGroupConversionRule implements ConversionRule {

    // It is extremely unlikely to encounter more than 10 groups in one of
    // our conversion reg-expressions
    final private static int MAX_GROUPS = 10;

    private final Pattern pattern;
    private final String[] replacementTable = new String[MAX_GROUPS];

    public MultiGroupConversionRule(Pattern pattern) {
        this.pattern = pattern;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.slf4j.converter.ConversionRule#getPattern()
     */
    public Pattern getPattern() {
        return pattern;
    }

    public void addReplacement(int groupIndex, String replacement) {
        if (groupIndex == 0) {
            throw new IllegalArgumentException("regex groups start at 1, not zero");
        }
        replacementTable[groupIndex] = replacement;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.slf4j.converter.ConversionRule#getReplacement(java.lang.Integer)
     */
    public String getReplacement(int groupIndex) {
        return replacementTable[groupIndex];
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.slf4j.converter.ConversionRule#replace(java.util.regex.Matcher)
     */
    public String replace(Matcher matcher) {
        StringBuilder replacementBuffer = new StringBuilder();
        String replacementText;

        for (int group = 1; group <= matcher.groupCount(); group++) {
            replacementText = getReplacement(group);
            if (replacementText != null) {
                // System.out.println("replacing group " + group + " : "
                // + matcher.group(group) + " with " + replacementText);
                replacementBuffer.append(replacementText);
            } else {
                replacementBuffer.append(matcher.group(group));
            }
        }
        return replacementBuffer.toString();
    }

    public String getAdditionalLine() {
        return null;
    }
}