Source code

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.layout;
018
019import java.nio.charset.Charset;
020import java.util.HashMap;
021import java.util.List;
022import java.util.Map;
023
024import org.apache.logging.log4j.core.Layout;
025import org.apache.logging.log4j.core.LogEvent;
026import org.apache.logging.log4j.core.config.Configuration;
027import org.apache.logging.log4j.core.config.DefaultConfiguration;
028import org.apache.logging.log4j.core.config.Node;
029import org.apache.logging.log4j.core.config.plugins.Plugin;
030import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
031import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
032import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
033import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
034import org.apache.logging.log4j.core.config.plugins.PluginElement;
035import org.apache.logging.log4j.core.config.plugins.PluginFactory;
036import org.apache.logging.log4j.core.pattern.LogEventPatternConverter;
037import org.apache.logging.log4j.core.pattern.PatternFormatter;
038import org.apache.logging.log4j.core.pattern.PatternParser;
039import org.apache.logging.log4j.core.pattern.RegexReplacement;
040
041/**
042 * A flexible layout configurable with pattern string.
043 * <p>
044 * The goal of this class is to {@link org.apache.logging.log4j.core.Layout#toByteArray format} a {@link LogEvent} and
045 * return the results. The format of the result depends on the <em>conversion pattern</em>.
046 * </p>
047 * <p>
048 * The conversion pattern is closely related to the conversion pattern of the printf function in C. A conversion pattern
049 * is composed of literal text and format control expressions called <em>conversion specifiers</em>.
050 * </p>
051 * <p>
052 * See the Log4j Manual for details on the supported pattern converters.
053 * </p>
054 */
055@Plugin(name = "PatternLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
056public final class PatternLayout extends AbstractStringLayout {
057
058    private static final long serialVersionUID = 1L;
059
060    /**
061     * Default pattern string for log output. Currently set to the
062     * string <b>"%m%n"</b> which just prints the application supplied
063     * message.
064     */
065    public static final String DEFAULT_CONVERSION_PATTERN = "%m%n";
066
067    /**
068     * A conversion pattern equivalent to the TTCCCLayout.
069     * Current value is <b>%r [%t] %p %c %x - %m%n</b>.
070     */
071    public static final String TTCC_CONVERSION_PATTERN =
072        "%r [%t] %p %c %x - %m%n";
073
074    /**
075     * A simple pattern.
076     * Current value is <b>%d [%t] %p %c - %m%n</b>.
077     */
078    public static final String SIMPLE_CONVERSION_PATTERN =
079        "%d [%t] %p %c - %m%n";
080
081    /** Key to identify pattern converters. */
082    public static final String KEY = "Converter";
083
084    /**
085     * Initial converter for pattern.
086     */
087    private final List<PatternFormatter> formatters;
088
089    /**
090     * Conversion pattern.
091     */
092    private final String conversionPattern;
093
094
095    /**
096     * The current Configuration.
097     */
098    private final Configuration config;
099
100    private final RegexReplacement replace;
101
102    private final boolean alwaysWriteExceptions;
103
104    private final boolean noConsoleNoAnsi;
105
106    /**
107     * Constructs a EnhancedPatternLayout using the supplied conversion pattern.
108     *
109     * @param config The Configuration.
110     * @param replace The regular expression to match.
111     * @param pattern conversion pattern.
112     * @param charset The character set.
113     * @param alwaysWriteExceptions Whether or not exceptions should always be handled in this pattern (if {@code true},
114     *                         exceptions will be written even if the pattern does not specify so).
115     * @param noConsoleNoAnsi
116     *            If {@code "true"} (default) and {@link System#console()} is null, do not output ANSI escape codes
117     * @param header
118     */
119    private PatternLayout(final Configuration config, final RegexReplacement replace, final String pattern,
120                          final Charset charset, final boolean alwaysWriteExceptions, final boolean noConsoleNoAnsi,
121                          final String header, final String footer) {
122        super(charset, toBytes(header, charset), toBytes(footer, charset));
123        this.replace = replace;
124        this.conversionPattern = pattern;
125        this.config = config;
126        this.alwaysWriteExceptions = alwaysWriteExceptions;
127        this.noConsoleNoAnsi = noConsoleNoAnsi;
128        final PatternParser parser = createPatternParser(config);
129        this.formatters = parser.parse(pattern == null ? DEFAULT_CONVERSION_PATTERN : pattern, this.alwaysWriteExceptions, this.noConsoleNoAnsi);
130    }
131
132    private static byte[] toBytes(final String str, final Charset charset) {
133        if (str != null) {
134            return str.getBytes(charset != null ? charset : Charset.defaultCharset());
135        }
136        return null;
137    }
138
139    private byte[] strSubstitutorReplace(final byte... b) {
140        if (b != null && config != null) {
141            return getBytes(config.getStrSubstitutor().replace(new String(b, getCharset())));
142        }
143        return b;
144    }
145
146    @Override
147    public byte[] getHeader() {
148        return strSubstitutorReplace(super.getHeader());
149    }
150
151    @Override
152    public byte[] getFooter() {
153        return strSubstitutorReplace(super.getFooter());
154    }
155
156    /**
157     * Gets the conversion pattern.
158     *
159     * @return the conversion pattern.
160     */
161    public String getConversionPattern() {
162        return conversionPattern;
163    }
164
165    /**
166     * Gets this PatternLayout's content format. Specified by:
167     * <ul>
168     * <li>Key: "structured" Value: "false"</li>
169     * <li>Key: "formatType" Value: "conversion" (format uses the keywords supported by OptionConverter)</li>
170     * <li>Key: "format" Value: provided "conversionPattern" param</li>
171     * </ul>
172     * 
173     * @return Map of content format keys supporting PatternLayout
174     */
175    @Override
176    public Map<String, String> getContentFormat()
177    {
178        final Map<String, String> result = new HashMap<String, String>();
179        result.put("structured", "false");
180        result.put("formatType", "conversion");
181        result.put("format", conversionPattern);
182        return result;
183    }
184
185    /**
186     * Formats a logging event to a writer.
187     *
188     *
189     * @param event logging event to be formatted.
190     * @return The event formatted as a String.
191     */
192    @Override
193    public String toSerializable(final LogEvent event) {
194        final StringBuilder buf = new StringBuilder();
195        for (final PatternFormatter formatter : formatters) {
196            formatter.format(event, buf);
197        }
198        String str = buf.toString();
199        if (replace != null) {
200            str = replace.format(str);
201        }
202        return str;
203    }
204
205    /**
206     * Create a PatternParser.
207     * @param config The Configuration.
208     * @return The PatternParser.
209     */
210    public static PatternParser createPatternParser(final Configuration config) {
211        if (config == null) {
212            return new PatternParser(config, KEY, LogEventPatternConverter.class);
213        }
214        PatternParser parser = config.getComponent(KEY);
215        if (parser == null) {
216            parser = new PatternParser(config, KEY, LogEventPatternConverter.class);
217            config.addComponent(KEY, parser);
218            parser = (PatternParser) config.getComponent(KEY);
219        }
220        return parser;
221    }
222
223    @Override
224    public String toString() {
225        return conversionPattern;
226    }
227
228    /**
229     * Create a pattern layout.
230     *
231     * @param pattern
232     *        The pattern. If not specified, defaults to DEFAULT_CONVERSION_PATTERN.
233     * @param config
234     *        The Configuration. Some Converters require access to the Interpolator.
235     * @param replace
236     *        A Regex replacement String.
237     * @param charset
238     *        The character set.
239     * @param alwaysWriteExceptions
240     *        If {@code "true"} (default) exceptions are always written even if the pattern contains no exception tokens.
241     * @param noConsoleNoAnsi
242     *        If {@code "true"} (default is false) and {@link System#console()} is null, do not output ANSI escape codes
243     * @param header
244     *        The footer to place at the top of the document, once.
245     * @param footer
246     *        The footer to place at the bottom of the document, once.
247     * @return The PatternLayout.
248     */
249    @PluginFactory
250    public static PatternLayout createLayout(
251            @PluginAttribute(value = "pattern", defaultString = DEFAULT_CONVERSION_PATTERN) final String pattern,
252            @PluginConfiguration final Configuration config,
253            @PluginElement("Replace") final RegexReplacement replace,
254            @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
255            @PluginAttribute(value = "alwaysWriteExceptions", defaultBoolean = true) final boolean alwaysWriteExceptions,
256            @PluginAttribute(value = "noConsoleNoAnsi", defaultBoolean = false) final boolean noConsoleNoAnsi,
257            @PluginAttribute("header") final String header,
258            @PluginAttribute("footer") final String footer) {
259        return newBuilder()
260            .withPattern(pattern)
261            .withConfiguration(config)
262            .withRegexReplacement(replace)
263            .withCharset(charset)
264            .withAlwaysWriteExceptions(alwaysWriteExceptions)
265            .withNoConsoleNoAnsi(noConsoleNoAnsi)
266            .withHeader(header)
267            .withFooter(footer)
268            .build();
269    }
270
271    /**
272     * Creates a PatternLayout using the default options. These options include using UTF-8, the default conversion
273     * pattern, exceptions being written, and with ANSI escape codes.
274     *
275     * @return the PatternLayout.
276     * @see #DEFAULT_CONVERSION_PATTERN Default conversion pattern
277     */
278    public static PatternLayout createDefaultLayout() {
279        return newBuilder().build();
280    }
281
282    /**
283     * Creates a builder for a custom PatternLayout.
284     * @return a PatternLayout builder.
285     */
286    @PluginBuilderFactory
287    public static Builder newBuilder() {
288        return new Builder();
289    }
290
291    /**
292     * Custom PatternLayout builder. Use the {@link PatternLayout#newBuilder() builder factory method} to create this.
293     */
294    public static class Builder implements org.apache.logging.log4j.core.util.Builder<PatternLayout> {
295
296        // FIXME: it seems rather redundant to repeat default values (same goes for field names)
297        // perhaps introduce a @PluginBuilderAttribute that has no values of its own and uses reflection?
298
299        @PluginBuilderAttribute
300        private String pattern = PatternLayout.DEFAULT_CONVERSION_PATTERN;
301
302        @PluginConfiguration
303        private Configuration configuration = null;
304
305        @PluginElement("Replace")
306        private RegexReplacement regexReplacement = null;
307
308        // LOG4J2-783 use platform default by default
309        @PluginBuilderAttribute
310        private Charset charset = Charset.defaultCharset();
311
312        @PluginBuilderAttribute
313        private boolean alwaysWriteExceptions = true;
314
315        @PluginBuilderAttribute
316        private boolean noConsoleNoAnsi = false;
317
318        @PluginBuilderAttribute
319        private String header = null;
320
321        @PluginBuilderAttribute
322        private String footer = null;
323
324        private Builder() {
325        }
326
327        // TODO: move javadocs from PluginFactory to here
328
329        public Builder withPattern(final String pattern) {
330            this.pattern = pattern;
331            return this;
332        }
333
334
335        public Builder withConfiguration(final Configuration configuration) {
336            this.configuration = configuration;
337            return this;
338        }
339
340        public Builder withRegexReplacement(final RegexReplacement regexReplacement) {
341            this.regexReplacement = regexReplacement;
342            return this;
343        }
344
345        public Builder withCharset(final Charset charset) {
346            this.charset = charset;
347            return this;
348        }
349
350        public Builder withAlwaysWriteExceptions(final boolean alwaysWriteExceptions) {
351            this.alwaysWriteExceptions = alwaysWriteExceptions;
352            return this;
353        }
354
355        public Builder withNoConsoleNoAnsi(final boolean noConsoleNoAnsi) {
356            this.noConsoleNoAnsi = noConsoleNoAnsi;
357            return this;
358        }
359
360        public Builder withHeader(final String header) {
361            this.header = header;
362            return this;
363        }
364
365        public Builder withFooter(final String footer) {
366            this.footer = footer;
367            return this;
368        }
369
370        @Override
371        public PatternLayout build() {
372            // fall back to DefaultConfiguration
373            if (configuration == null) {
374                configuration = new DefaultConfiguration();
375            }
376            return new PatternLayout(configuration, regexReplacement, pattern, charset, alwaysWriteExceptions,
377                noConsoleNoAnsi, header, footer);
378        }
379    }
380}