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.message;
018    
019    import java.text.SimpleDateFormat;
020    import java.util.Arrays;
021    import java.util.Collection;
022    import java.util.Date;
023    import java.util.HashSet;
024    import java.util.Map;
025    import java.util.Set;
026    
027    /**
028     * Handles messages that consist of a format string containing '{}' to represent each replaceable token, and
029     * the parameters.
030     * <p/>
031     * This class was originally written for Lillith (http://mac.freshmeat.net/projects/lilith-viewer) by
032     * Joern Huxhorn where it is licensed under the LGPL. It has been relicensed here with his permission
033     * providing that this attribution remain.
034     */
035    public class ParameterizedMessage implements Message {
036    
037        /**
038         * Prefix for recursion.
039         */
040        public static final String RECURSION_PREFIX = "[...";
041        /**
042         * Suffix for recursion.
043         */
044        public static final String RECURSION_SUFFIX = "...]";
045    
046        /**
047         * Prefix for errors.
048         */
049        public static final String ERROR_PREFIX = "[!!!";
050        /**
051         * Separator for errors.
052         */
053        public static final String ERROR_SEPARATOR = "=>";
054        /**
055         * Separator for error messages.
056         */
057        public static final String ERROR_MSG_SEPARATOR = ":";
058        /**
059         * Suffix for errors.
060         */
061        public static final String ERROR_SUFFIX = "!!!]";
062    
063        private static final long serialVersionUID = -665975803997290697L;
064    
065        private static final int HASHVAL = 31;
066    
067        private static final char DELIM_START = '{';
068        private static final char DELIM_STOP = '}';
069        private static final char ESCAPE_CHAR = '\\';
070    
071        private final String messagePattern;
072        private String[] stringArgs;
073        private transient Object[] argArray;
074        private transient String formattedMessage;
075        private transient Throwable throwable;
076    
077        /**
078         * Create the parameterizedMessage.
079         * @param messagePattern The message "format" string. This will be a String containing "{}" placeholders
080         * where parameters should be substituted.
081         * @param stringArgs The arguments for substitution.
082         * @param throwable A Throwable.
083         */
084        public ParameterizedMessage(final String messagePattern, final String[] stringArgs, final Throwable throwable) {
085            this.messagePattern = messagePattern;
086            this.stringArgs = stringArgs;
087            this.throwable = throwable;
088        }
089    
090        public ParameterizedMessage(final String messagePattern, final Object[] arguments, final Throwable throwable) {
091            this.messagePattern = messagePattern;
092            this.throwable = throwable;
093            if (arguments != null) {
094                parseArguments(arguments);
095            }
096        }
097    
098        /**
099         * <p>This method returns a ParameterizedMessage which contains the arguments converted to String
100         * as well as an optional Throwable.</p>
101         * <p/>
102         * <p>If the last argument is a Throwable and is NOT used up by a placeholder in the message pattern it is returned
103         * in ParameterizedMessage.getThrowable() and won't be contained in the created String[].<br/>
104         * If it is used up ParameterizedMessage.getThrowable() will return null even if the last argument was a
105         * Throwable!</p>
106         *
107         * @param messagePattern the message pattern that to be checked for placeholders.
108         * @param arguments      the argument array to be converted.
109         */
110        public ParameterizedMessage(final String messagePattern, final Object[] arguments) {
111            this.messagePattern = messagePattern;
112            if (arguments != null) {
113                parseArguments(arguments);
114            }
115        }
116    
117        /**
118         * Constructor with a pattern and a single parameter.
119         * @param messagePattern The message pattern.
120         * @param arg The parameter.
121         */
122        public ParameterizedMessage(final String messagePattern, final Object arg) {
123            this(messagePattern, new Object[]{arg});
124        }
125    
126        /**
127         * Constructor with a pattern and two parameters.
128         * @param messagePattern The message pattern.
129         * @param arg1 The first parameter.
130         * @param arg2 The second parameter.
131         */
132        public ParameterizedMessage(final String messagePattern, final Object arg1, final Object arg2) {
133            this(messagePattern, new Object[]{arg1, arg2});
134        }
135    
136        private void parseArguments(final Object[] arguments) {
137            final int argsCount = countArgumentPlaceholders(messagePattern);
138            int resultArgCount = arguments.length;
139            if (argsCount < arguments.length) {
140                if (throwable == null && arguments[arguments.length - 1] instanceof Throwable) {
141                    throwable = (Throwable) arguments[arguments.length - 1];
142                    resultArgCount--;
143                }
144            }
145            argArray = new Object[resultArgCount];
146            for (int i = 0; i < resultArgCount; ++i) {
147                argArray[i] = arguments[i];
148            }
149    
150            if (argsCount == 1 && throwable == null && arguments.length > 1) {
151                // special case
152                stringArgs = new String[1];
153                stringArgs[0] = deepToString(arguments);
154            } else {
155                stringArgs = new String[resultArgCount];
156                for (int i = 0; i < stringArgs.length; i++) {
157                    stringArgs[i] = deepToString(arguments[i]);
158                }
159            }
160        }
161    
162        /**
163         * Returns the formatted message.
164         * @return the formatted message.
165         */
166        public String getFormattedMessage() {
167            if (formattedMessage == null) {
168                formattedMessage = formatMessage(messagePattern, stringArgs);
169            }
170            return formattedMessage;
171        }
172    
173        /**
174         * Returns the message pattern.
175         * @return the message pattern.
176         */
177        public String getFormat() {
178            return messagePattern;
179        }
180    
181        /**
182         * Returns the message parameters.
183         * @return the message parameters.
184         */
185        public Object[] getParameters() {
186            if (argArray != null) {
187                return argArray;
188            }
189            return stringArgs;
190        }
191    
192        /**
193         * Returns the Throwable that was given as the last argument, if any.
194         * It will not survive serialization. The Throwable exists as part of the message
195         * primarily so that it can be extracted from the end of the list of parameters
196         * and then be added to the LogEvent. As such, the Throwable in the event should
197         * not be used once the LogEvent has been constructed.
198         *
199         * @return the Throwable, if any.
200         */
201        public Throwable getThrowable() {
202            return throwable;
203        }
204    
205        protected String formatMessage(final String msgPattern, final String[] sArgs) {
206            return format(msgPattern, sArgs);
207        }
208    
209        @Override
210        public boolean equals(final Object o) {
211            if (this == o) {
212                return true;
213            }
214            if (o == null || getClass() != o.getClass()) {
215                return false;
216            }
217    
218            final ParameterizedMessage that = (ParameterizedMessage) o;
219    
220            if (messagePattern != null ? !messagePattern.equals(that.messagePattern) : that.messagePattern != null) {
221                return false;
222            }
223            if (!Arrays.equals(stringArgs, that.stringArgs)) {
224                return false;
225            }
226            //if (throwable != null ? !throwable.equals(that.throwable) : that.throwable != null) return false;
227    
228            return true;
229        }
230    
231        @Override
232        public int hashCode() {
233            int result = messagePattern != null ? messagePattern.hashCode() : 0;
234            result = HASHVAL * result + (stringArgs != null ? Arrays.hashCode(stringArgs) : 0);
235            return result;
236        }
237    
238        /**
239         * Replace placeholders in the given messagePattern with arguments.
240         *
241         * @param messagePattern the message pattern containing placeholders.
242         * @param arguments      the arguments to be used to replace placeholders.
243         * @return the formatted message.
244         */
245        public static String format(final String messagePattern, final Object[] arguments) {
246            if (messagePattern == null || arguments == null || arguments.length == 0) {
247                return messagePattern;
248            }
249    
250            final StringBuilder result = new StringBuilder();
251            int escapeCounter = 0;
252            int currentArgument = 0;
253            for (int i = 0; i < messagePattern.length(); i++) {
254                final char curChar = messagePattern.charAt(i);
255                if (curChar == ESCAPE_CHAR) {
256                    escapeCounter++;
257                } else {
258                    if (curChar == DELIM_START) {
259                        if (i < messagePattern.length() - 1) {
260                            if (messagePattern.charAt(i + 1) == DELIM_STOP) {
261                                // write escaped escape chars
262                                final int escapedEscapes = escapeCounter / 2;
263                                for (int j = 0; j < escapedEscapes; j++) {
264                                    result.append(ESCAPE_CHAR);
265                                }
266    
267                                if (escapeCounter % 2 == 1) {
268                                    // i.e. escaped
269                                    // write escaped escape chars
270                                    result.append(DELIM_START);
271                                    result.append(DELIM_STOP);
272                                } else {
273                                    // unescaped
274                                    if (currentArgument < arguments.length) {
275                                        result.append(arguments[currentArgument]);
276                                    } else {
277                                        result.append(DELIM_START).append(DELIM_STOP);
278                                    }
279                                    currentArgument++;
280                                }
281                                i++;
282                                escapeCounter = 0;
283                                continue;
284                            }
285                        }
286                    }
287                    // any other char beside ESCAPE or DELIM_START/STOP-combo
288                    // write unescaped escape chars
289                    if (escapeCounter > 0) {
290                        for (int j = 0; j < escapeCounter; j++) {
291                            result.append(ESCAPE_CHAR);
292                        }
293                        escapeCounter = 0;
294                    }
295                    result.append(curChar);
296                }
297            }
298            return result.toString();
299        }
300    
301        /**
302         * Counts the number of unescaped placeholders in the given messagePattern.
303         *
304         * @param messagePattern the message pattern to be analyzed.
305         * @return the number of unescaped placeholders.
306         */
307        public static int countArgumentPlaceholders(final String messagePattern) {
308            if (messagePattern == null) {
309                return 0;
310            }
311    
312            final int delim = messagePattern.indexOf(DELIM_START);
313    
314            if (delim == -1) {
315                // special case, no placeholders at all.
316                return 0;
317            }
318            int result = 0;
319            boolean isEscaped = false;
320            for (int i = 0; i < messagePattern.length(); i++) {
321                final char curChar = messagePattern.charAt(i);
322                if (curChar == ESCAPE_CHAR) {
323                    isEscaped = !isEscaped;
324                } else if (curChar == DELIM_START) {
325                    if (!isEscaped) {
326                        if (i < messagePattern.length() - 1) {
327                            if (messagePattern.charAt(i + 1) == DELIM_STOP) {
328                                result++;
329                                i++;
330                            }
331                        }
332                    }
333                    isEscaped = false;
334                } else {
335                    isEscaped = false;
336                }
337            }
338            return result;
339        }
340    
341        /**
342         * This method performs a deep toString of the given Object.
343         * Primitive arrays are converted using their respective Arrays.toString methods while
344         * special handling is implemented for "container types", i.e. Object[], Map and Collection because those could
345         * contain themselves.
346         * <p/>
347         * It should be noted that neither AbstractMap.toString() nor AbstractCollection.toString() implement such a
348         * behavior. They only check if the container is directly contained in itself, but not if a contained container
349         * contains the original one. Because of that, Arrays.toString(Object[]) isn't safe either.
350         * Confusing? Just read the last paragraph again and check the respective toString() implementation.
351         * <p/>
352         * This means, in effect, that logging would produce a usable output even if an ordinary System.out.println(o)
353         * would produce a relatively hard-to-debug StackOverflowError.
354         * @param o The object.
355         * @return The String representation.
356         */
357        public static String deepToString(final Object o) {
358            if (o == null) {
359                return null;
360            }
361            if (o instanceof String) {
362                return (String) o;
363            }
364            final StringBuilder str = new StringBuilder();
365            final Set<String> dejaVu = new HashSet<String>(); // that's actually a neat name ;)
366            recursiveDeepToString(o, str, dejaVu);
367            return str.toString();
368        }
369    
370        /**
371         * This method performs a deep toString of the given Object.
372         * Primitive arrays are converted using their respective Arrays.toString methods while
373         * special handling is implemented for "container types", i.e. Object[], Map and Collection because those could
374         * contain themselves.
375         * <p/>
376         * dejaVu is used in case of those container types to prevent an endless recursion.
377         * <p/>
378         * It should be noted that neither AbstractMap.toString() nor AbstractCollection.toString() implement such a
379         * behavior.
380         * They only check if the container is directly contained in itself, but not if a contained container contains the
381         * original one. Because of that, Arrays.toString(Object[]) isn't safe either.
382         * Confusing? Just read the last paragraph again and check the respective toString() implementation.
383         * <p/>
384         * This means, in effect, that logging would produce a usable output even if an ordinary System.out.println(o)
385         * would produce a relatively hard-to-debug StackOverflowError.
386         *
387         * @param o      the Object to convert into a String
388         * @param str    the StringBuilder that o will be appended to
389         * @param dejaVu a list of container identities that were already used.
390         */
391        private static void recursiveDeepToString(final Object o, final StringBuilder str, final Set<String> dejaVu) {
392            if (o == null) {
393                str.append("null");
394                return;
395            }
396            if (o instanceof String) {
397                str.append(o);
398                return;
399            }
400    
401            final Class<?> oClass = o.getClass();
402            if (oClass.isArray()) {
403                if (oClass == byte[].class) {
404                    str.append(Arrays.toString((byte[]) o));
405                } else if (oClass == short[].class) {
406                    str.append(Arrays.toString((short[]) o));
407                } else if (oClass == int[].class) {
408                    str.append(Arrays.toString((int[]) o));
409                } else if (oClass == long[].class) {
410                    str.append(Arrays.toString((long[]) o));
411                } else if (oClass == float[].class) {
412                    str.append(Arrays.toString((float[]) o));
413                } else if (oClass == double[].class) {
414                    str.append(Arrays.toString((double[]) o));
415                } else if (oClass == boolean[].class) {
416                    str.append(Arrays.toString((boolean[]) o));
417                } else if (oClass == char[].class) {
418                    str.append(Arrays.toString((char[]) o));
419                } else {
420                    // special handling of container Object[]
421                    final String id = identityToString(o);
422                    if (dejaVu.contains(id)) {
423                        str.append(RECURSION_PREFIX).append(id).append(RECURSION_SUFFIX);
424                    } else {
425                        dejaVu.add(id);
426                        final Object[] oArray = (Object[]) o;
427                        str.append("[");
428                        boolean first = true;
429                        for (final Object current : oArray) {
430                            if (first) {
431                                first = false;
432                            } else {
433                                str.append(", ");
434                            }
435                            recursiveDeepToString(current, str, new HashSet<String>(dejaVu));
436                        }
437                        str.append("]");
438                    }
439                    //str.append(Arrays.deepToString((Object[]) o));
440                }
441            } else if (o instanceof Map) {
442                // special handling of container Map
443                final String id = identityToString(o);
444                if (dejaVu.contains(id)) {
445                    str.append(RECURSION_PREFIX).append(id).append(RECURSION_SUFFIX);
446                } else {
447                    dejaVu.add(id);
448                    final Map<?, ?> oMap = (Map<?, ?>) o;
449                    str.append("{");
450                    boolean isFirst = true;
451                    for (final Object o1 : oMap.entrySet()) {
452                        final Map.Entry<?, ?> current = (Map.Entry<?, ?>) o1;
453                        if (isFirst) {
454                            isFirst = false;
455                        } else {
456                            str.append(", ");
457                        }
458                        final Object key = current.getKey();
459                        final Object value = current.getValue();
460                        recursiveDeepToString(key, str, new HashSet<String>(dejaVu));
461                        str.append("=");
462                        recursiveDeepToString(value, str, new HashSet<String>(dejaVu));
463                    }
464                    str.append("}");
465                }
466            } else if (o instanceof Collection) {
467                // special handling of container Collection
468                final String id = identityToString(o);
469                if (dejaVu.contains(id)) {
470                    str.append(RECURSION_PREFIX).append(id).append(RECURSION_SUFFIX);
471                } else {
472                    dejaVu.add(id);
473                    final Collection<?> oCol = (Collection<?>) o;
474                    str.append("[");
475                    boolean isFirst = true;
476                    for (final Object anOCol : oCol) {
477                        if (isFirst) {
478                            isFirst = false;
479                        } else {
480                            str.append(", ");
481                        }
482                        recursiveDeepToString(anOCol, str, new HashSet<String>(dejaVu));
483                    }
484                    str.append("]");
485                }
486            } else if (o instanceof Date) {
487                final Date date = (Date) o;
488                final SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
489                // I'll leave it like this for the moment... this could probably be optimized using ThreadLocal...
490                str.append(format.format(date));
491            } else {
492                // it's just some other Object, we can only use toString().
493                try {
494                    str.append(o.toString());
495                } catch (final Throwable t) {
496                    str.append(ERROR_PREFIX);
497                    str.append(identityToString(o));
498                    str.append(ERROR_SEPARATOR);
499                    final String msg = t.getMessage();
500                    final String className = t.getClass().getName();
501                    str.append(className);
502                    if (!className.equals(msg)) {
503                        str.append(ERROR_MSG_SEPARATOR);
504                        str.append(msg);
505                    }
506                    str.append(ERROR_SUFFIX);
507                }
508            }
509        }
510    
511        /**
512         * This method returns the same as if Object.toString() would not have been
513         * overridden in obj.
514         * <p/>
515         * Note that this isn't 100% secure as collisions can always happen with hash codes.
516         * <p/>
517         * Copied from Object.hashCode():
518         * As much as is reasonably practical, the hashCode method defined by
519         * class <tt>Object</tt> does return distinct integers for distinct
520         * objects. (This is typically implemented by converting the internal
521         * address of the object into an integer, but this implementation
522         * technique is not required by the
523         * Java<font size="-2"><sup>TM</sup></font>
524         * programming language.)
525         *
526         * @param obj the Object that is to be converted into an identity string.
527         * @return the identity string as also defined in Object.toString()
528         */
529        public static String identityToString(final Object obj) {
530            if (obj == null) {
531                return null;
532            }
533            return obj.getClass().getName() + "@" + Integer.toHexString(System.identityHashCode(obj));
534        }
535    
536        @Override
537        public String toString() {
538            return "ParameterizedMessage[messagePattern=" + messagePattern + ", stringArgs=" +
539                Arrays.toString(stringArgs) + ", throwable=" + throwable + "]";
540        }
541    }