001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.appender.rolling;
018
019import java.text.NumberFormat;
020import java.text.ParseException;
021import java.util.Locale;
022import java.util.regex.Matcher;
023import java.util.regex.Pattern;
024
025import org.apache.logging.log4j.Logger;
026import org.apache.logging.log4j.core.LogEvent;
027import org.apache.logging.log4j.core.config.plugins.Plugin;
028import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
029import org.apache.logging.log4j.core.config.plugins.PluginFactory;
030import org.apache.logging.log4j.status.StatusLogger;
031
032/**
033 *
034 */
035@Plugin(name = "SizeBasedTriggeringPolicy", category = "Core", printObject = true)
036public class SizeBasedTriggeringPolicy implements TriggeringPolicy {
037    /**
038     * Allow subclasses access to the status logger without creating another instance.
039     */
040    protected static final Logger LOGGER = StatusLogger.getLogger();
041
042    private static final long KB = 1024;
043    private static final long MB = KB * KB;
044    private static final long GB = KB * MB;
045
046    /**
047     * Rollover threshold size in bytes.
048     */
049    private static final long MAX_FILE_SIZE = 10 * 1024 * 1024; // let 10 MB the default max size
050
051
052    /**
053     * Pattern for string parsing.
054     */
055    private static final Pattern VALUE_PATTERN =
056        Pattern.compile("([0-9]+([\\.,][0-9]+)?)\\s*(|K|M|G)B?", Pattern.CASE_INSENSITIVE);
057
058    private final long maxFileSize;
059
060    private RollingFileManager manager;
061
062    /**
063     * Constructs a new instance.
064     */
065    protected SizeBasedTriggeringPolicy() {
066        this.maxFileSize = MAX_FILE_SIZE;
067    }
068
069    /**
070     * Constructs a new instance.
071     *
072     * @param maxFileSize rollover threshold size in bytes.
073     */
074    protected SizeBasedTriggeringPolicy(final long maxFileSize) {
075        this.maxFileSize = maxFileSize;
076    }
077
078    /**
079     * Initialize the TriggeringPolicy.
080     * @param manager The RollingFileManager.
081     */
082    @Override
083    public void initialize(final RollingFileManager manager) {
084        this.manager = manager;
085    }
086
087
088    /**
089     * Returns true if a rollover should occur.
090     * @param event   A reference to the currently event.
091     * @return true if a rollover should take place, false otherwise.
092     */
093    @Override
094    public boolean isTriggeringEvent(final LogEvent event) {
095        return manager.getFileSize() > maxFileSize;
096    }
097
098    @Override
099    public String toString() {
100        return "SizeBasedTriggeringPolicy(size=" + maxFileSize + ")";
101    }
102
103    /**
104     * Create a SizeBasedTriggeringPolicy.
105     * @param size The size of the file before rollover is required.
106     * @return A SizeBasedTriggeringPolicy.
107     */
108    @PluginFactory
109    public static SizeBasedTriggeringPolicy createPolicy(@PluginAttribute("size") final String size) {
110
111        final long maxSize = size == null ? MAX_FILE_SIZE : valueOf(size);
112        return new SizeBasedTriggeringPolicy(maxSize);
113    }
114
115    /**
116     * Converts a string to a number of bytes. Strings consist of a floating point value followed by
117     * K, M, or G for kilobytes, megabytes, gigabytes, respectively. The
118     * abbreviations KB, MB, and GB are also accepted. Matching is case insensitive.
119     *
120     * @param string The string to convert
121     * @return The Bytes value for the string
122     */
123    private static long valueOf(final String string) {
124        final Matcher matcher = VALUE_PATTERN.matcher(string);
125
126        // Valid input?
127        if (matcher.matches()) {
128            try {
129                // Get double precision value
130                final long value = NumberFormat.getNumberInstance(Locale.getDefault()).parse(
131                    matcher.group(1)).longValue();
132
133                // Get units specified
134                final String units = matcher.group(3);
135
136                if (units.equalsIgnoreCase("")) {
137                    return value;
138                } else if (units.equalsIgnoreCase("K")) {
139                    return value * KB;
140                } else if (units.equalsIgnoreCase("M")) {
141                    return value * MB;
142                } else if (units.equalsIgnoreCase("G")) {
143                    return value * GB;
144                } else {
145                    LOGGER.error("Units not recognized: " + string);
146                    return MAX_FILE_SIZE;
147                }
148            } catch (final ParseException e) {
149                LOGGER.error("Unable to parse numeric part: " + string, e);
150                return MAX_FILE_SIZE;
151            }
152        }
153        LOGGER.error("Unable to parse bytes: " + string);
154        return MAX_FILE_SIZE;
155    }
156}