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.classic.pattern;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import static java.util.regex.Pattern.quote;
import ch.qos.logback.classic.spi.CallerData;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.Context;
import ch.qos.logback.core.CoreConstants;
import ch.qos.logback.core.boolex.EvaluationException;
import ch.qos.logback.core.boolex.EventEvaluator;
import ch.qos.logback.core.status.ErrorStatus;

This converter outputs caller data depending on depth or depth range and marker data.
Author:
Ceki Gulcu/**
 * This converter outputs caller data depending on depth or depth range and marker data.
 * 
 * @author Ceki Gulcu
 */
public class CallerDataConverter extends ClassicConverter {

    public static final String DEFAULT_CALLER_LINE_PREFIX = "Caller+";

    public static final String DEFAULT_RANGE_DELIMITER = "..";

    private int depthStart = 0;
    private int depthEnd = 5;
    List<EventEvaluator<ILoggingEvent>> evaluatorList = null;

    final int MAX_ERROR_COUNT = 4;
    int errorCount = 0;

    @SuppressWarnings("unchecked")
    public void start() {
        String depthStr = getFirstOption();
        if (depthStr == null) {
            return;
        }

        try {
            if (isRange(depthStr)) {
                String[] numbers = splitRange(depthStr);
                if (numbers.length == 2) {
                    depthStart = Integer.parseInt(numbers[0]);
                    depthEnd = Integer.parseInt(numbers[1]);
                    checkRange();
                } else {
                    addError("Failed to parse depth option as range [" + depthStr + "]");
                }
            } else {
                depthEnd = Integer.parseInt(depthStr);
            }
        } catch (NumberFormatException nfe) {
            addError("Failed to parse depth option [" + depthStr + "]", nfe);
        }

        final List<String> optionList = getOptionList();

        if (optionList != null && optionList.size() > 1) {
            final int optionListSize = optionList.size();
            for (int i = 1; i < optionListSize; i++) {
                String evaluatorStr = optionList.get(i);
                Context context = getContext();
                if (context != null) {
                    Map<String, EventEvaluator<?>> evaluatorMap = (Map<String, EventEvaluator<?>>) context.getObject(CoreConstants.EVALUATOR_MAP);
                    EventEvaluator<ILoggingEvent> ee = (EventEvaluator<ILoggingEvent>) evaluatorMap.get(evaluatorStr);
                    if (ee != null) {
                        addEvaluator(ee);
                    }
                }
            }
        }
    }

    private boolean isRange(String depthStr) {
        return depthStr.contains(getDefaultRangeDelimiter());
    }

    private String[] splitRange(String depthStr) {
        return depthStr.split(quote(getDefaultRangeDelimiter()), 2);
    }

    private void checkRange() {
        if (depthStart < 0 || depthEnd < 0) {
            addError("Invalid depthStart/depthEnd range [" + depthStart + ", " + depthEnd + "] (negative values are not allowed)");
        } else if (depthStart >= depthEnd) {
            addError("Invalid depthEnd range [" + depthStart + ", " + depthEnd + "] (start greater or equal to end)");
        }
    }

    private void addEvaluator(EventEvaluator<ILoggingEvent> ee) {
        if (evaluatorList == null) {
            evaluatorList = new ArrayList<EventEvaluator<ILoggingEvent>>();
        }
        evaluatorList.add(ee);
    }

    public String convert(ILoggingEvent le) {
        StringBuilder buf = new StringBuilder();

        if (evaluatorList != null) {
            boolean printCallerData = false;
            for (int i = 0; i < evaluatorList.size(); i++) {
                EventEvaluator<ILoggingEvent> ee = evaluatorList.get(i);
                try {
                    if (ee.evaluate(le)) {
                        printCallerData = true;
                        break;
                    }
                } catch (EvaluationException eex) {
                    errorCount++;
                    if (errorCount < MAX_ERROR_COUNT) {
                        addError("Exception thrown for evaluator named [" + ee.getName() + "]", eex);
                    } else if (errorCount == MAX_ERROR_COUNT) {
                        ErrorStatus errorStatus = new ErrorStatus("Exception thrown for evaluator named [" + ee.getName() + "].", this, eex);
                        errorStatus.add(new ErrorStatus("This was the last warning about this evaluator's errors."
                                        + "We don't want the StatusManager to get flooded.", this));
                        addStatus(errorStatus);
                    }

                }
            }

            if (!printCallerData) {
                return CoreConstants.EMPTY_STRING;
            }
        }

        StackTraceElement[] cda = le.getCallerData();
        if (cda != null && cda.length > depthStart) {
            int limit = depthEnd < cda.length ? depthEnd : cda.length;

            for (int i = depthStart; i < limit; i++) {
                buf.append(getCallerLinePrefix());
                buf.append(i);
                buf.append("\t at ");
                buf.append(cda[i]);
                buf.append(CoreConstants.LINE_SEPARATOR);
            }
            return buf.toString();
        } else {
            return CallerData.CALLER_DATA_NA;
        }
    }

    protected String getCallerLinePrefix() {
        return DEFAULT_CALLER_LINE_PREFIX;
    }

    protected String getDefaultRangeDelimiter() {
        return DEFAULT_RANGE_DELIMITER;
    }
}