    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.commons.logging.impl;
    018
    019import static org.slf4j.spi.LocationAwareLogger.DEBUG_INT;
    020import static org.slf4j.spi.LocationAwareLogger.ERROR_INT;
    021import static org.slf4j.spi.LocationAwareLogger.INFO_INT;
    022import static org.slf4j.spi.LocationAwareLogger.TRACE_INT;
    023import static org.slf4j.spi.LocationAwareLogger.WARN_INT;
    024
    025import java.util.concurrent.ConcurrentHashMap;
    026import java.util.concurrent.ConcurrentMap;
    027
    028import org.apache.commons.logging.Log;
    029import org.apache.commons.logging.LogConfigurationException;
    030import org.apache.commons.logging.LogFactory;
    031import org.slf4j.ILoggerFactory;
    032import org.slf4j.Logger;
    033import org.slf4j.LoggerFactory;
    034import org.slf4j.Marker;
    035import org.slf4j.MarkerFactory;
    036import org.slf4j.spi.LocationAwareLogger;
    037
    038/**
    039 * Logger factory hardcoded to send everything to SLF4J.
    040 *
    041 * @since 1.3.0
    042 */
    043public final class Slf4jLogFactory extends LogFactory {
    044
    045    private static final class Slf4jLocationAwareLog implements Log {
    046
    047        private static final String FQCN = Slf4jLocationAwareLog.class.getName();
    048
    049        private final LocationAwareLogger logger;
    050
    051        public Slf4jLocationAwareLog(final LocationAwareLogger logger) {
    052            this.logger = logger;
    053        }
    054
    055        @Override
    056        public void debug(final Object message) {
    057            log(DEBUG_INT, message, null);
    058        }
    059
    060        @Override
    061        public void debug(final Object message, final Throwable t) {
    062            log(DEBUG_INT, message, t);
    063        }
    064
    065        @Override
    066        public void error(final Object message) {
    067            log(ERROR_INT, message, null);
    068        }
    069
    070        @Override
    071        public void error(final Object message, final Throwable t) {
    072            log(ERROR_INT, message, t);
    073        }
    074
    075        @Override
    076        public void fatal(final Object message) {
    077            error(message);
    078        }
    079
    080        @Override
    081        public void fatal(final Object message, final Throwable t) {
    082            error(message, t);
    083        }
    084
    085        @Override
    086        public void info(final Object message) {
    087            log(INFO_INT, message, null);
    088        }
    089
    090        @Override
    091        public void info(final Object message, final Throwable t) {
    092            log(INFO_INT, message, t);
    093        }
    094
    095        @Override
    096        public boolean isDebugEnabled() {
    097            return logger.isDebugEnabled(MARKER);
    098        }
    099
    100        @Override
    101        public boolean isErrorEnabled() {
    102            return logger.isErrorEnabled(MARKER);
    103        }
    104
    105        @Override
    106        public boolean isFatalEnabled() {
    107            return isErrorEnabled();
    108        }
    109
    110        @Override
    111        public boolean isInfoEnabled() {
    112            return logger.isInfoEnabled(MARKER);
    113        }
    114
    115        @Override
    116        public boolean isTraceEnabled() {
    117            return logger.isTraceEnabled(MARKER);
    118        }
    119
    120        @Override
    121        public boolean isWarnEnabled() {
    122            return logger.isWarnEnabled(MARKER);
    123        }
    124
    125        private void log(final int level, final Object message, final Throwable t) {
    126            logger.log(MARKER, FQCN, level, String.valueOf(message), EMPTY_OBJECT_ARRAY, t);
    127        }
    128
    129        @Override
    130        public void trace(final Object message) {
    131            log(TRACE_INT, message, null);
    132        }
    133
    134        @Override
    135        public void trace(final Object message, final Throwable t) {
    136            log(TRACE_INT, message, t);
    137        }
    138
    139        @Override
    140        public void warn(final Object message) {
    141            log(WARN_INT, message, null);
    142        }
    143
    144        @Override
    145        public void warn(final Object message, final Throwable t) {
    146            log(WARN_INT, message, t);
    147        }
    148    }
    149    private static class Slf4jLog implements Log {
    150
    151        private final Logger logger;
    152
    153        public Slf4jLog(final Logger logger) {
    154            this.logger = logger;
    155        }
    156
    157        @Override
    158        public void debug(final Object message) {
    159            logger.debug(MARKER, String.valueOf(message));
    160        }
    161
    162        @Override
    163        public void debug(final Object message, final Throwable t) {
    164            logger.debug(MARKER, String.valueOf(message), t);
    165        }
    166
    167        @Override
    168        public void error(final Object message) {
    169            logger.error(MARKER, String.valueOf(message));
    170        }
    171
    172        @Override
    173        public void error(final Object message, final Throwable t) {
    174            logger.debug(MARKER, String.valueOf(message), t);
    175        }
    176
    177        @Override
    178        public void fatal(final Object message) {
    179            error(message);
    180        }
    181
    182        @Override
    183        public void fatal(final Object message, final Throwable t) {
    184            error(message, t);
    185        }
    186
    187        @Override
    188        public void info(final Object message) {
    189            logger.info(MARKER, String.valueOf(message));
    190        }
    191
    192        @Override
    193        public void info(final Object message, final Throwable t) {
    194            logger.info(MARKER, String.valueOf(message), t);
    195        }
    196
    197        @Override
    198        public boolean isDebugEnabled() {
    199            return logger.isDebugEnabled(MARKER);
    200        }
    201
    202        @Override
    203        public boolean isErrorEnabled() {
    204            return logger.isErrorEnabled(MARKER);
    205        }
    206
    207        @Override
    208        public boolean isFatalEnabled() {
    209            return isErrorEnabled();
    210        }
    211
    212        @Override
    213        public boolean isInfoEnabled() {
    214            return logger.isInfoEnabled(MARKER);
    215        }
    216
    217        @Override
    218        public boolean isTraceEnabled() {
    219            return logger.isTraceEnabled(MARKER);
    220        }
    221
    222        @Override
    223        public boolean isWarnEnabled() {
    224            return logger.isWarnEnabled(MARKER);
    225        }
    226
    227        @Override
    228        public void trace(final Object message) {
    229            logger.trace(MARKER, String.valueOf(message));
    230        }
    231
    232        @Override
    233        public void trace(final Object message, final Throwable t) {
    234            logger.trace(MARKER, String.valueOf(message), t);
    235        }
    236
    237        @Override
    238        public void warn(final Object message) {
    239            logger.warn(MARKER, String.valueOf(message));
    240        }
    241
    242        @Override
    243        public void warn(final Object message, final Throwable t) {
    244            logger.warn(MARKER, String.valueOf(message), t);
    245        }
    246    }
    247
    248    private static final Object[] EMPTY_OBJECT_ARRAY = {};
    249
    250    private static final String[] EMPTY_STRING_ARRAY = {};
    251
    252    /**
    253     * Marker used by all messages coming from Apache Commons Logging.
    254     */
    255    private static final Marker MARKER = MarkerFactory.getMarker("COMMONS-LOGGING");
    256
    257    /**
    258     * Caches Log instances.
    259     * <p>
    260     * The SLF4J reference implementation (Logback) has a single logger context, so each call to
    261     * {@link #getInstance(String)}
    262     * should give the same result.
    263     * </p>
    264     */
    265    private final ConcurrentMap<String, Log> loggers = new ConcurrentHashMap<>();
    266
    267    private final ConcurrentMap<String, Object> attributes = new ConcurrentHashMap<>();
    268
    269    /**
    270     * Constructs a new instance.
    271     */
    272    public Slf4jLogFactory() {
    273        // empty
    274    }
    275
    276    @Override
    277    public Object getAttribute(final String name) {
    278        return attributes.get(name);
    279    }
    280
    281    @Override
    282    public String[] getAttributeNames() {
    283        return attributes.keySet().toArray(EMPTY_STRING_ARRAY);
    284    }
    285
    286    @Override
    287    public Log getInstance(final Class<?> clazz) throws LogConfigurationException {
    288        return getInstance(clazz.getName());
    289    }
    290
    291    @Override
    292    public Log getInstance(final String name) {
    293        return loggers.computeIfAbsent(name, n -> {
    294            final Logger logger = LoggerFactory.getLogger(n);
    295            return logger instanceof LocationAwareLogger ? new Slf4jLocationAwareLog((LocationAwareLogger) logger) : new Slf4jLog(
    296                    logger);
    297        });
    298    }
    299
    300    /**
    301     * This method is supposed to clear all loggers.
    302     * <p>
    303     * In this implementation it calls a "stop" method if the logger factory supports it. This is the case of
    304     * Logback.
    305     * </p>
    306     */
    307    @Override
    308    public void release() {
    309        final ILoggerFactory factory = LoggerFactory.getILoggerFactory();
    310        try {
    311            factory.getClass().getMethod("stop").invoke(factory);
    312        } catch (final ReflectiveOperationException ignored) {
    313            // empty
    314        }
    315    }
    316
    317    @Override
    318    public void removeAttribute(final String name) {
    319        attributes.remove(name);
    320    }
    321
    322    @Override
    323    public void setAttribute(final String name, final Object value) {
    324        if (value != null) {
    325            attributes.put(name, value);
    326        } else {
    327            removeAttribute(name);
    328        }
    329    }
    330}