001/**
002 * Logback: the reliable, generic, fast and flexible logging framework.
003 * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
004 *
005 * This program and the accompanying materials are dual-licensed under
006 * either the terms of the Eclipse Public License v1.0 as published by
007 * the Eclipse Foundation
008 *
009 *   or (per the licensee's choosing)
010 *
011 * under the terms of the GNU Lesser General Public License version 2.1
012 * as published by the Free Software Foundation.
013 */
014package ch.qos.logback.core.rolling;
015
016import ch.qos.logback.core.FileAppender;
017import ch.qos.logback.core.rolling.helper.CompressionMode;
018import ch.qos.logback.core.rolling.helper.FileNamePattern;
019import ch.qos.logback.core.spi.ContextAwareBase;
020
021import static ch.qos.logback.core.util.Loader.isClassLoadable;
022
023/**
024 * Implements methods common to most, it not all, rolling policies. Currently
025 * such methods are limited to a compression mode getter/setter.
026 *
027 * @author Ceki Gülcü
028 */
029public abstract class RollingPolicyBase extends ContextAwareBase implements RollingPolicy {
030    protected CompressionMode compressionMode = CompressionMode.NONE;
031
032    FileNamePattern fileNamePattern;
033    // fileNamePatternStr is always slashified, see setter
034    protected String fileNamePatternStr;
035
036    private FileAppender<?> parent;
037
038    // use to name files within zip file, i.e. the zipEntry
039    FileNamePattern zipEntryFileNamePattern;
040    private boolean started;
041
042    /**
043     * Given the FileNamePattern string, this method determines the compression mode
044     * depending on last letters of the fileNamePatternStr. Patterns ending with .gz
045     * imply GZIP compression, endings with '.zip' imply ZIP compression, endings with
046     * .xz imply XZ compression. Otherwise and by default, there is no compression.
047     *
048     */
049    protected void determineCompressionMode() {
050        if (fileNamePatternStr.endsWith(CompressionMode.GZ_SUFFIX)) {
051            addInfo("Will use gz compression");
052            compressionMode = CompressionMode.GZ;
053        } else if (fileNamePatternStr.endsWith(CompressionMode.ZIP_SUFFIX)) {
054            addInfo("Will use zip compression");
055            compressionMode = CompressionMode.ZIP;
056        } else if (fileNamePatternStr.endsWith(CompressionMode.XZ_SUFFIX)) {
057            addInfo("Will use xz compression");
058            compressionMode = CompressionMode.XZ;
059        } else {
060            addInfo("No compression will be used");
061            compressionMode = CompressionMode.NONE;
062        }
063    }
064
065    /**
066     * If compression mode is XZ but the XZ library is missing, then fallback to GZ compression.
067     */
068    protected void adjustCompressionModeAndFileNamePatternStrIfNecessary() {
069        if (compressionMode == compressionMode.XZ) {
070            boolean xzLibraryLoadable = isClassLoadable("org.tukaani.xz.XZOutputStream", getContext());
071            if (!xzLibraryLoadable) {
072                addWarn("XZ library missing, falling back to GZ compression");
073                compressionMode = CompressionMode.GZ;
074                fileNamePatternStr = replaceSuffix(fileNamePatternStr, CompressionMode.XZ_SUFFIX, CompressionMode.GZ_SUFFIX);
075            }
076        }
077    }
078
079    private String replaceSuffix(String input, String existingSuffix, String newSuffix) {
080        int existingSuffixLen = existingSuffix.length();
081        if (input.endsWith(existingSuffix)) {
082            return input.substring(0, input.length() - existingSuffixLen) + newSuffix;
083        } else {
084            // unreachable code
085            throw new IllegalArgumentException("[" + input + "] should end with "+existingSuffix);
086        }
087    }
088
089    public void setFileNamePattern(String fnp) {
090        fileNamePatternStr = fnp;
091    }
092
093    public String getFileNamePattern() {
094        return fileNamePatternStr;
095    }
096
097    public CompressionMode getCompressionMode() {
098        return compressionMode;
099    }
100
101    public boolean isStarted() {
102        return started;
103    }
104
105    public void start() {
106        started = true;
107    }
108
109    public void stop() {
110        started = false;
111    }
112
113    public void setParent(FileAppender<?> appender) {
114        this.parent = appender;
115    }
116
117    public boolean isParentPrudent() {
118        return parent.isPrudent();
119    }
120
121    public String getParentsRawFileProperty() {
122        return parent.rawFileProperty();
123    }
124}