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     */
017    package org.apache.logging.log4j.core.appender.rolling;
018    
019    import org.apache.logging.log4j.Logger;
020    import org.apache.logging.log4j.core.LogEvent;
021    import org.apache.logging.log4j.core.config.plugins.Plugin;
022    import org.apache.logging.log4j.core.config.plugins.PluginAttr;
023    import org.apache.logging.log4j.core.config.plugins.PluginFactory;
024    import org.apache.logging.log4j.status.StatusLogger;
025    
026    import java.text.NumberFormat;
027    import java.text.ParseException;
028    import java.util.Locale;
029    import java.util.regex.Matcher;
030    import java.util.regex.Pattern;
031    
032    /**
033     *
034     */
035    @Plugin(name = "SizeBasedTriggeringPolicy", category = "Core", printObject = true)
036    public 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(@PluginAttr("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            } else {
153                LOGGER.error("Unable to parse bytes: " + string);
154                return MAX_FILE_SIZE;
155            }
156        }
157    }