001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2018 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle;
021
022import java.io.OutputStream;
023import java.io.OutputStreamWriter;
024import java.io.PrintWriter;
025import java.io.StringWriter;
026import java.nio.charset.StandardCharsets;
027import java.util.ArrayList;
028import java.util.Collections;
029import java.util.List;
030import java.util.Locale;
031import java.util.Map;
032import java.util.ResourceBundle;
033import java.util.concurrent.ConcurrentHashMap;
034
035import com.puppycrawl.tools.checkstyle.api.AuditEvent;
036import com.puppycrawl.tools.checkstyle.api.AuditListener;
037import com.puppycrawl.tools.checkstyle.api.AutomaticBean;
038import com.puppycrawl.tools.checkstyle.api.SeverityLevel;
039import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
040
041/**
042 * Simple XML logger.
043 * It outputs everything in UTF-8 (default XML encoding is UTF-8) in case
044 * we want to localize error messages or simply that file names are
045 * localized and takes care about escaping as well.
046
047 */
048// -@cs[AbbreviationAsWordInName] We can not change it as,
049// check's name is part of API (used in configurations).
050public class XMLLogger
051    extends AutomaticBean
052    implements AuditListener {
053
054    /** Decimal radix. */
055    private static final int BASE_10 = 10;
056
057    /** Hex radix. */
058    private static final int BASE_16 = 16;
059
060    /** Some known entities to detect. */
061    private static final String[] ENTITIES = {"gt", "amp", "lt", "apos",
062                                              "quot", };
063
064    /** Close output stream in auditFinished. */
065    private final boolean closeStream;
066
067    /** The writer lock object. */
068    private final Object writerLock = new Object();
069
070    /** Holds all messages for the given file. */
071    private final Map<String, FileMessages> fileMessages =
072            new ConcurrentHashMap<>();
073
074    /**
075     * Helper writer that allows easy encoding and printing.
076     */
077    private final PrintWriter writer;
078
079    /**
080     * Creates a new {@code XMLLogger} instance.
081     * Sets the output to a defined stream.
082     * @param outputStream the stream to write logs to.
083     * @param closeStream close oS in auditFinished
084     * @deprecated in order to fulfill demands of BooleanParameter IDEA check.
085     * @noinspection BooleanParameter
086     */
087    @Deprecated
088    public XMLLogger(OutputStream outputStream, boolean closeStream) {
089        writer = new PrintWriter(new OutputStreamWriter(outputStream, StandardCharsets.UTF_8));
090        this.closeStream = closeStream;
091    }
092
093    /**
094     * Creates a new {@code XMLLogger} instance.
095     * Sets the output to a defined stream.
096     * @param outputStream the stream to write logs to.
097     * @param outputStreamOptions if {@code CLOSE} stream should be closed in auditFinished()
098     */
099    public XMLLogger(OutputStream outputStream, OutputStreamOptions outputStreamOptions) {
100        writer = new PrintWriter(new OutputStreamWriter(outputStream, StandardCharsets.UTF_8));
101        closeStream = outputStreamOptions == OutputStreamOptions.CLOSE;
102    }
103
104    @Override
105    protected void finishLocalSetup() {
106        // No code by default
107    }
108
109    @Override
110    public void auditStarted(AuditEvent event) {
111        writer.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
112
113        final ResourceBundle compilationProperties =
114            ResourceBundle.getBundle("checkstylecompilation", Locale.ROOT);
115        final String version =
116            compilationProperties.getString("checkstyle.compile.version");
117
118        writer.println("<checkstyle version=\"" + version + "\">");
119    }
120
121    @Override
122    public void auditFinished(AuditEvent event) {
123        writer.println("</checkstyle>");
124        if (closeStream) {
125            writer.close();
126        }
127        else {
128            writer.flush();
129        }
130    }
131
132    @Override
133    public void fileStarted(AuditEvent event) {
134        fileMessages.put(event.getFileName(), new FileMessages());
135    }
136
137    @Override
138    public void fileFinished(AuditEvent event) {
139        final String fileName = event.getFileName();
140        final FileMessages messages = fileMessages.get(fileName);
141
142        synchronized (writerLock) {
143            writeFileMessages(fileName, messages);
144        }
145
146        fileMessages.remove(fileName);
147    }
148
149    /**
150     * Prints the file section with all file errors and exceptions.
151     * @param fileName The file name, as should be printed in the opening file tag.
152     * @param messages The file messages.
153     */
154    private void writeFileMessages(String fileName, FileMessages messages) {
155        writeFileOpeningTag(fileName);
156        if (messages != null) {
157            for (AuditEvent errorEvent : messages.getErrors()) {
158                writeFileError(errorEvent);
159            }
160            for (Throwable exception : messages.getExceptions()) {
161                writeException(exception);
162            }
163        }
164        writeFileClosingTag();
165    }
166
167    /**
168     * Prints the "file" opening tag with the given filename.
169     * @param fileName The filename to output.
170     */
171    private void writeFileOpeningTag(String fileName) {
172        writer.println("<file name=\"" + encode(fileName) + "\">");
173    }
174
175    /**
176     * Prints the "file" closing tag.
177     */
178    private void writeFileClosingTag() {
179        writer.println("</file>");
180    }
181
182    @Override
183    public void addError(AuditEvent event) {
184        if (event.getSeverityLevel() != SeverityLevel.IGNORE) {
185            final String fileName = event.getFileName();
186            if (fileName == null || !fileMessages.containsKey(fileName)) {
187                synchronized (writerLock) {
188                    writeFileError(event);
189                }
190            }
191            else {
192                final FileMessages messages = fileMessages.get(fileName);
193                messages.addError(event);
194            }
195        }
196    }
197
198    /**
199     * Outputs the given event to the writer.
200     * @param event An event to print.
201     */
202    private void writeFileError(AuditEvent event) {
203        writer.print("<error" + " line=\"" + event.getLine() + "\"");
204        if (event.getColumn() > 0) {
205            writer.print(" column=\"" + event.getColumn() + "\"");
206        }
207        writer.print(" severity=\""
208                + event.getSeverityLevel().getName()
209                + "\"");
210        writer.print(" message=\""
211                + encode(event.getMessage())
212                + "\"");
213        writer.print(" source=\"");
214        if (event.getModuleId() == null) {
215            writer.print(encode(event.getSourceName()));
216        }
217        else {
218            writer.print(encode(event.getModuleId()));
219        }
220        writer.println("\"/>");
221    }
222
223    @Override
224    public void addException(AuditEvent event, Throwable throwable) {
225        final String fileName = event.getFileName();
226        if (fileName == null || !fileMessages.containsKey(fileName)) {
227            synchronized (writerLock) {
228                writeException(throwable);
229            }
230        }
231        else {
232            final FileMessages messages = fileMessages.get(fileName);
233            messages.addException(throwable);
234        }
235    }
236
237    /**
238     * Writes the exception event to the print writer.
239     * @param throwable The
240     */
241    private void writeException(Throwable throwable) {
242        writer.println("<exception>");
243        writer.println("<![CDATA[");
244
245        final StringWriter stringWriter = new StringWriter();
246        final PrintWriter printer = new PrintWriter(stringWriter);
247        throwable.printStackTrace(printer);
248        writer.println(encode(stringWriter.toString()));
249
250        writer.println("]]>");
251        writer.println("</exception>");
252    }
253
254    /**
255     * Escape &lt;, &gt; &amp; &#39; and &quot; as their entities.
256     * @param value the value to escape.
257     * @return the escaped value if necessary.
258     */
259    public static String encode(String value) {
260        final StringBuilder sb = new StringBuilder(256);
261        for (int i = 0; i < value.length(); i++) {
262            final char chr = value.charAt(i);
263            switch (chr) {
264                case '<':
265                    sb.append("&lt;");
266                    break;
267                case '>':
268                    sb.append("&gt;");
269                    break;
270                case '\'':
271                    sb.append("&apos;");
272                    break;
273                case '\"':
274                    sb.append("&quot;");
275                    break;
276                case '&':
277                    sb.append("&amp;");
278                    break;
279                case '\r':
280                    break;
281                case '\n':
282                    sb.append("&#10;");
283                    break;
284                default:
285                    if (Character.isISOControl(chr)) {
286                        // true escape characters need '&' before but it also requires XML 1.1
287                        // until https://github.com/checkstyle/checkstyle/issues/5168
288                        sb.append("#x");
289                        sb.append(Integer.toHexString(chr));
290                        sb.append(';');
291                    }
292                    else {
293                        sb.append(chr);
294                    }
295                    break;
296            }
297        }
298        return sb.toString();
299    }
300
301    /**
302     * Finds whether the given argument is character or entity reference.
303     * @param ent the possible entity to look for.
304     * @return whether the given argument a character or entity reference
305     */
306    public static boolean isReference(String ent) {
307        boolean reference = false;
308
309        if (ent.charAt(0) != '&' || !CommonUtils.endsWithChar(ent, ';')) {
310            reference = false;
311        }
312        else if (ent.charAt(1) == '#') {
313            // prefix is "&#"
314            int prefixLength = 2;
315
316            int radix = BASE_10;
317            if (ent.charAt(2) == 'x') {
318                prefixLength++;
319                radix = BASE_16;
320            }
321            try {
322                Integer.parseInt(
323                    ent.substring(prefixLength, ent.length() - 1), radix);
324                reference = true;
325            }
326            catch (final NumberFormatException ignored) {
327                reference = false;
328            }
329        }
330        else {
331            final String name = ent.substring(1, ent.length() - 1);
332            for (String element : ENTITIES) {
333                if (name.equals(element)) {
334                    reference = true;
335                    break;
336                }
337            }
338        }
339        return reference;
340    }
341
342    /**
343     * The registered file messages.
344     */
345    private static class FileMessages {
346
347        /** The file error events. */
348        private final List<AuditEvent> errors = Collections.synchronizedList(new ArrayList<>());
349
350        /** The file exceptions. */
351        private final List<Throwable> exceptions = Collections.synchronizedList(new ArrayList<>());
352
353        /**
354         * Returns the file error events.
355         * @return the file error events.
356         */
357        public List<AuditEvent> getErrors() {
358            return Collections.unmodifiableList(errors);
359        }
360
361        /**
362         * Adds the given error event to the messages.
363         * @param event the error event.
364         */
365        public void addError(AuditEvent event) {
366            errors.add(event);
367        }
368
369        /**
370         * Returns the file exceptions.
371         * @return the file exceptions.
372         */
373        public List<Throwable> getExceptions() {
374            return Collections.unmodifiableList(exceptions);
375        }
376
377        /**
378         * Adds the given exception to the messages.
379         * @param throwable the file exception
380         */
381        public void addException(Throwable throwable) {
382            exceptions.add(throwable);
383        }
384
385    }
386
387}