1 /*

     2  * Copyright 2010 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  */

    23 

    24 import java.awt.BorderLayout;

    25 import java.awt.Color;

    26 import java.awt.Dimension;

    27 import java.awt.EventQueue;

    28 import java.awt.Font;

    29 import java.awt.GridBagConstraints;

    30 import java.awt.GridBagLayout;

    31 import java.awt.Rectangle;

    32 import java.awt.event.ActionEvent;

    33 import java.awt.event.ActionListener;

    34 import java.awt.event.MouseAdapter;

    35 import java.awt.event.MouseEvent;

    36 import java.io.File;

    37 import java.io.IOException;

    38 import java.io.PrintStream;

    39 import java.io.PrintWriter;

    40 import java.io.StringWriter;

    41 import java.lang.reflect.Field;

    42 import java.lang.reflect.Modifier;

    43 import java.nio.charset.Charset;

    44 import java.util.ArrayList;

    45 import java.util.Collections;

    46 import java.util.HashMap;

    47 import java.util.HashSet;

    48 import java.util.Iterator;

    49 import java.util.List;

    50 import java.util.Map;

    51 import java.util.Set;

    52 import javax.swing.DefaultComboBoxModel;

    53 import javax.swing.JComboBox;

    54 import javax.swing.JComponent;

    55 import javax.swing.JFrame;

    56 import javax.swing.JLabel;

    57 import javax.swing.JPanel;

    58 import javax.swing.JScrollPane;

    59 import javax.swing.JTextArea;

    60 import javax.swing.JTextField;

    61 import javax.swing.SwingUtilities;

    62 import javax.swing.event.CaretEvent;

    63 import javax.swing.event.CaretListener;

    64 import javax.swing.text.BadLocationException;

    65 import javax.swing.text.DefaultHighlighter;

    66 import javax.swing.text.Highlighter;

    67 import javax.tools.Diagnostic;

    68 import javax.tools.DiagnosticListener;

    69 import javax.tools.JavaFileObject;

    70 import javax.tools.StandardJavaFileManager;

    71 

    72 import com.sun.source.tree.CompilationUnitTree;

    73 import com.sun.source.util.JavacTask;

    74 import com.sun.tools.javac.api.JavacTool;

    75 import com.sun.tools.javac.code.Flags;

    76 import com.sun.tools.javac.tree.JCTree;

    77 import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;

    78 import com.sun.tools.javac.tree.JCTree.JCNewClass;

    79 import com.sun.tools.javac.tree.JCTree.JCVariableDecl;

    80 import com.sun.tools.javac.tree.TreeInfo;

    81 import com.sun.tools.javac.tree.TreeScanner;

    82 

    83 import static com.sun.tools.javac.util.Position.NOPOS;

    84 

    85 /**

    86  * Utility and test program to check validity of tree positions for tree nodes.

    87  * The program can be run standalone, or as a jtreg test.  In standalone mode,

    88  * errors can be displayed in a gui viewer. For info on command line args,

    89  * run program with no args.

    90  *

    91  * <p>

    92  * jtreg: Note that by using the -r switch in the test description below, this test

    93  * will process all java files in the langtools/test directory, thus implicitly

    94  * covering any new language features that may be tested in this test suite.

    95  */

    96 

    97 /*

    98  * @test

    99  * @bug 6919889

   100  * @summary assorted position errors in compiler syntax trees

   101  * @run main TreePosTest -q -r -ef ./tools/javac/typeAnnotations -ef ./tools/javap/typeAnnotations -et ANNOTATED_TYPE .

   102  */

   103 public class TreePosTest {

   104     /**

   105      * Main entry point.

   106      * If test.src is set, program runs in jtreg mode, and will throw an Error

   107      * if any errors arise, otherwise System.exit will be used, unless the gui

   108      * viewer is being used. In jtreg mode, the default base directory for file

   109      * args is the value of ${test.src}. In jtreg mode, the -r option can be

   110      * given to change the default base directory to the root test directory.

   111      */

   112     public static void main(String... args) {

   113         String testSrc = System.getProperty("test.src");

   114         File baseDir = (testSrc == null) ? null : new File(testSrc);

   115         boolean ok = new TreePosTest().run(baseDir, args);

   116         if (!ok) {

   117             if (testSrc != null)  // jtreg mode

   118                 throw new Error("failed");

   119             else

   120                 System.exit(1);

   121         }

   122     }

   123 

   124     /**

   125      * Run the program. A base directory can be provided for file arguments.

   126      * In jtreg mode, the -r option can be given to change the default base

   127      * directory to the test root directory. For other options, see usage().

   128      * @param baseDir base directory for any file arguments.

   129      * @param args command line args

   130      * @return true if successful or in gui mode

   131      */

   132     boolean run(File baseDir, String... args) {

   133         if (args.length == 0) {

   134             usage(System.out);

   135             return true;

   136         }

   137 

   138         List<File> files = new ArrayList<File>();

   139         for (int i = 0; i < args.length; i++) {

   140             String arg = args[i];

   141             if (arg.equals("-encoding") && i + 1 < args.length)

   142                 encoding = args[++i];

   143             else if (arg.equals("-gui"))

   144                 gui = true;

   145             else if (arg.equals("-q"))

   146                 quiet = true;

   147             else if (arg.equals("-v"))

   148                 verbose = true;

   149             else if (arg.equals("-t") && i + 1 < args.length)

   150                 tags.add(args[++i]);

   151             else if (arg.equals("-ef") && i + 1 < args.length)

   152                 excludeFiles.add(new File(baseDir, args[++i]));

   153             else if (arg.equals("-et") && i + 1 < args.length)

   154                 excludeTags.add(args[++i]);

   155             else if (arg.equals("-r")) {

   156                 if (excludeFiles.size() > 0)

   157                     throw new Error("-r must be used before -ef");

   158                 File d = baseDir;

   159                 while (!new File(d, "TEST.ROOT").exists()) {

   160                     d = d.getParentFile();

   161                     if (d == null)

   162                         throw new Error("cannot find TEST.ROOT");

   163                 }

   164                 baseDir = d;

   165             }

   166             else if (arg.startsWith("-"))

   167                 throw new Error("unknown option: " + arg);

   168             else {

   169                 while (i < args.length)

   170                     files.add(new File(baseDir, args[i++]));

   171             }

   172         }

   173 

   174         for (File file: files) {

   175             if (file.exists())

   176                 test(file);

   177             else

   178                 error("File not found: " + file);

   179         }

   180 

   181         if (fileCount != 1)

   182             System.err.println(fileCount + " files read");

   183         if (errors > 0)

   184             System.err.println(errors + " errors");

   185 

   186         return (gui || errors == 0);

   187     }

   188 

   189     /**

   190      * Print command line help.

   191      * @param out output stream

   192      */

   193     void usage(PrintStream out) {

   194         out.println("Usage:");

   195         out.println("  java TreePosTest options... files...");

   196         out.println("");

   197         out.println("where options include:");

   198         out.println("-gui      Display returns in a GUI viewer");

   199         out.println("-q        Quiet: don't report on inapplicable files");

   200         out.println("-v        Verbose: report on files as they are being read");

   201         out.println("-t tag    Limit checks to tree nodes with this tag");

   202         out.println("          Can be repeated if desired");

   203         out.println("-ef file  Exclude file or directory");

   204         out.println("-et tag   Exclude tree nodes with given tag name");

   205         out.println("");

   206         out.println("files may be directories or files");

   207         out.println("directories will be scanned recursively");

   208         out.println("non java files, or java files which cannot be parsed, will be ignored");

   209         out.println("");

   210     }

   211 

   212     /**

   213      * Test a file. If the file is a directory, it will be recursively scanned

   214      * for java files.

   215      * @param file the file or directory to test

   216      */

   217     void test(File file) {

   218         if (excludeFiles.contains(file)) {

   219             if (!quiet)

   220                 error("File " + file + " excluded");

   221             return;

   222         }

   223 

   224         if (file.isDirectory()) {

   225             for (File f: file.listFiles()) {

   226                 test(f);

   227             }

   228             return;

   229         }

   230 

   231         if (file.isFile() && file.getName().endsWith(".java")) {

   232             try {

   233                 if (verbose)

   234                     System.err.println(file);

   235                 fileCount++;

   236                 PosTester p = new PosTester();

   237                 p.test(read(file));

   238             } catch (ParseException e) {

   239                 if (!quiet) {

   240                     error("Error parsing " + file + "\n" + e.getMessage());

   241                 }

   242             } catch (IOException e) {

   243                 error("Error reading " + file + ": " + e);

   244             }

   245             return;

   246         }

   247 

   248         if (!quiet)

   249             error("File " + file + " ignored");

   250     }

   251 

   252     /**

   253      * Read a file.

   254      * @param file the file to be read

   255      * @return the tree for the content of the file

   256      * @throws IOException if any IO errors occur

   257      * @throws TreePosTest.ParseException if any errors occur while parsing the file

   258      */

   259     JCCompilationUnit read(File file) throws IOException, ParseException {

   260         StringWriter sw = new StringWriter();

   261         PrintWriter pw = new PrintWriter(sw);

   262         Reporter r = new Reporter(pw);

   263         JavacTool tool = JavacTool.create();

   264         Charset cs = (encoding == null ? null : Charset.forName(encoding));

   265         StandardJavaFileManager fm = tool.getStandardFileManager(r, null, null);

   266         Iterable<? extends JavaFileObject> files = fm.getJavaFileObjects(file);

   267         JavacTask task = tool.getTask(pw, fm, r, Collections.<String>emptyList(), null, files);

   268         Iterable<? extends CompilationUnitTree> trees = task.parse();

   269         pw.flush();

   270         if (r.errors > 0)

   271             throw new ParseException(sw.toString());

   272         Iterator<? extends CompilationUnitTree> iter = trees.iterator();

   273         if (!iter.hasNext())

   274             throw new Error("no trees found");

   275         JCCompilationUnit t = (JCCompilationUnit) iter.next();

   276         if (iter.hasNext())

   277             throw new Error("too many trees found");

   278         return t;

   279     }

   280 

   281     /**

   282      * Report an error. When the program is complete, the program will either

   283      * exit or throw an Error if any errors have been reported.

   284      * @param msg the error message

   285      */

   286     void error(String msg) {

   287         System.err.println(msg);

   288         errors++;

   289     }

   290 

   291     /** Number of files that have been analyzed. */

   292     int fileCount;

   293     /** Number of errors reported. */

   294     int errors;

   295     /** Flag: don't report irrelevant files. */

   296     boolean quiet;

   297     /** Flag: report files as they are processed. */

   298     boolean verbose;

   299     /** Flag: show errors in GUI viewer. */

   300     boolean gui;

   301     /** Option: encoding for test files. */

   302     String encoding;

   303     /** The GUI viewer for errors. */

   304     Viewer viewer;

   305     /** The set of tags for tree nodes to be analyzed; if empty, all tree nodes

   306      * are analyzed. */

   307     Set<String> tags = new HashSet<String>();

   308     /** Set of files and directories to be excluded from analysis. */

   309     Set<File> excludeFiles = new HashSet<File>();

   310     /** Set of tag names to be excluded from analysis. */

   311     Set<String> excludeTags = new HashSet<String>();

   312     /** Table of printable names for tree tag values. */

   313     TagNames tagNames = new TagNames();

   314 

   315     /**

   316      * Main class for testing assertions concerning tree positions for tree nodes.

   317      */

   318     private class PosTester extends TreeScanner {

   319         void test(JCCompilationUnit tree) {

   320             sourcefile = tree.sourcefile;

   321             endPosTable = tree.endPositions;

   322             encl = new Info();

   323             tree.accept(this);

   324         }

   325 

   326         @Override

   327         public void scan(JCTree tree) {

   328             if (tree == null)

   329                 return;

   330 

   331             Info self = new Info(tree, endPosTable);

   332             if (check(encl, self)) {

   333                 // Modifiers nodes are present throughout the tree even where

   334                 // there is no corresponding source text.

   335                 // Redundant semicolons in a class definition can cause empty

   336                 // initializer blocks with no positions.

   337                 if ((self.tag == JCTree.MODIFIERS || self.tag == JCTree.BLOCK)

   338                         && self.pos == NOPOS) {

   339                     // If pos is NOPOS, so should be the start and end positions

   340                     check("start == NOPOS", encl, self, self.start == NOPOS);

   341                     check("end == NOPOS", encl, self, self.end == NOPOS);

   342                 } else {

   343                     // For this node, start , pos, and endpos should be all defined

   344                     check("start != NOPOS", encl, self, self.start != NOPOS);

   345                     check("pos != NOPOS", encl, self, self.pos != NOPOS);

   346                     check("end != NOPOS", encl, self, self.end != NOPOS);

   347                     // The following should normally be ordered

   348                     // encl.start <= start <= pos <= end <= encl.end

   349                     // In addition, the position of the enclosing node should be

   350                     // within this node.

   351                     // The primary exceptions are for array type nodes, because of the

   352                     // need to support legacy syntax:

   353                     //    e.g.    int a[];    int[] b[];    int f()[] { return null; }

   354                     // and because of inconsistent nesting of left and right of

   355                     // array declarations:

   356                     //    e.g.    int[][] a = new int[2][];

   357                     check("encl.start <= start", encl, self, encl.start <= self.start);

   358                     check("start <= pos", encl, self, self.start <= self.pos);

   359                     if (!(self.tag == JCTree.TYPEARRAY

   360                             && (encl.tag == JCTree.VARDEF || encl.tag == JCTree.TYPEARRAY))) {

   361                         check("encl.pos <= start || end <= encl.pos",

   362                                 encl, self, encl.pos <= self.start || self.end <= encl.pos);

   363                     }

   364                     check("pos <= end", encl, self, self.pos <= self.end);

   365                     if (!(self.tag == JCTree.TYPEARRAY && encl.tag == JCTree.TYPEARRAY)) {

   366                         check("end <= encl.end", encl, self, self.end <= encl.end);

   367                     }

   368                 }

   369             }

   370 

   371             Info prevEncl = encl;

   372             encl = self;

   373             tree.accept(this);

   374             encl = prevEncl;

   375         }

   376 

   377         @Override

   378         public void visitVarDef(JCVariableDecl tree) {

   379             // enum member declarations are desugared in the parser and have

   380             // ill-defined semantics for tree positions, so for now, we

   381             // skip the synthesized bits and just check parts which came from

   382             // the original source text

   383             if ((tree.mods.flags & Flags.ENUM) != 0) {

   384                 scan(tree.mods);

   385                 if (tree.init != null) {

   386                     if (tree.init.getTag() == JCTree.NEWCLASS) {

   387                         JCNewClass init = (JCNewClass) tree.init;

   388                         if (init.args != null && init.args.nonEmpty()) {

   389                             scan(init.args);

   390                         }

   391                         if (init.def != null && init.def.defs != null) {

   392                             scan(init.def.defs);

   393                         }

   394                     }

   395                 }

   396             } else

   397                 super.visitVarDef(tree);

   398         }

   399 

   400         boolean check(Info encl, Info self) {

   401             if (excludeTags.size() > 0) {

   402                 if (encl != null && excludeTags.contains(tagNames.get(encl.tag))

   403                         || excludeTags.contains(tagNames.get(self.tag)))

   404                     return false;

   405             }

   406             return tags.size() == 0 || tags.contains(tagNames.get(self.tag));

   407         }

   408 

   409         void check(String label, Info encl, Info self, boolean ok) {

   410             if (!ok) {

   411                 if (gui) {

   412                     if (viewer == null)

   413                         viewer = new Viewer();

   414                     viewer.addEntry(sourcefile, label, encl, self);

   415                 }

   416 

   417                 String s = self.tree.toString();

   418                 String msg = sourcefile.getName() + ": " + label + ": " +

   419                         "encl:" + encl + " this:" + self + "\n" +

   420                         s.substring(0, Math.min(80, s.length())).replaceAll("[\r\n]+", " ");

   421                 error(msg);

   422             }

   423         }

   424 

   425         JavaFileObject sourcefile;

   426         Map<JCTree, Integer> endPosTable;

   427         Info encl;

   428 

   429     }

   430 

   431     /**

   432      * Utility class providing easy access to position and other info for a tree node.

   433      */

   434     private class Info {

   435         Info() {

   436             tree = null;

   437             tag = JCTree.ERRONEOUS;

   438             start = 0;

   439             pos = 0;

   440             end = Integer.MAX_VALUE;

   441         }

   442 

   443         Info(JCTree tree, Map<JCTree, Integer> endPosTable) {

   444             this.tree = tree;

   445             tag = tree.getTag();

   446             start = TreeInfo.getStartPos(tree);

   447             pos = tree.pos;

   448             end = TreeInfo.getEndPos(tree, endPosTable);

   449         }

   450 

   451         @Override

   452         public String toString() {

   453             return tagNames.get(tree.getTag()) + "[start:" + start + ",pos:" + pos + ",end:" + end + "]";

   454         }

   455 

   456         final JCTree tree;

   457         final int tag;

   458         final int start;

   459         final int pos;

   460         final int end;

   461     }

   462 

   463     /**

   464      * Names for tree tags.

   465      * javac does not provide an API to convert tag values to strings, so this class uses

   466      * reflection to determine names of public static final int values in JCTree.

   467      */

   468     private static class TagNames {

   469         String get(int tag) {

   470             if (map == null) {

   471                 map = new HashMap<Integer, String>();

   472                 Class c = JCTree.class;

   473                 for (Field f : c.getDeclaredFields()) {

   474                     if (f.getType().equals(int.class)) {

   475                         int mods = f.getModifiers();

   476                         if (Modifier.isPublic(mods) && Modifier.isStatic(mods) && Modifier.isFinal(mods)) {

   477                             try {

   478                                 map.put(f.getInt(null), f.getName());

   479                             } catch (IllegalAccessException e) {

   480                             }

   481                         }

   482                     }

   483                 }

   484             }

   485             String name = map.get(tag);

   486             return (name == null) ? "??" : name;

   487         }

   488 

   489         private Map<Integer, String> map;

   490     }

   491 

   492     /**

   493      * Thrown when errors are found parsing a java file.

   494      */

   495     private static class ParseException extends Exception {

   496         ParseException(String msg) {

   497             super(msg);

   498         }

   499     }

   500 

   501     /**

   502      * DiagnosticListener to report diagnostics and count any errors that occur.

   503      */

   504     private static class Reporter implements DiagnosticListener<JavaFileObject> {

   505         Reporter(PrintWriter out) {

   506             this.out = out;

   507         }

   508 

   509         public void report(Diagnostic<? extends JavaFileObject> diagnostic) {

   510             out.println(diagnostic);

   511             switch (diagnostic.getKind()) {

   512                 case ERROR:

   513                     errors++;

   514             }

   515         }

   516         int errors;

   517         PrintWriter out;

   518     }

   519 

   520     /**

   521      * GUI viewer for issues found by TreePosTester. The viewer provides a drop

   522      * down list for selecting error conditions, a header area providing details

   523      * about an error, and a text area with the ranges of text highlighted as

   524      * appropriate.

   525      */

   526     private class Viewer extends JFrame {

   527         /**

   528          * Create a viewer.

   529          */

   530         Viewer() {

   531             initGUI();

   532         }

   533 

   534         /**

   535          * Add another entry to the list of errors.

   536          * @param file The file containing the error

   537          * @param check The condition that was being tested, and which failed

   538          * @param encl the enclosing tree node

   539          * @param self the tree node containing the error

   540          */

   541         void addEntry(JavaFileObject file, String check, Info encl, Info self) {

   542             Entry e = new Entry(file, check, encl, self);

   543             DefaultComboBoxModel m = (DefaultComboBoxModel) entries.getModel();

   544             m.addElement(e);

   545             if (m.getSize() == 1)

   546                 entries.setSelectedItem(e);

   547         }

   548 

   549         /**

   550          * Initialize the GUI window.

   551          */

   552         private void initGUI() {

   553             JPanel head = new JPanel(new GridBagLayout());

   554             GridBagConstraints lc = new GridBagConstraints();

   555             GridBagConstraints fc = new GridBagConstraints();

   556             fc.anchor = GridBagConstraints.WEST;

   557             fc.fill = GridBagConstraints.HORIZONTAL;

   558             fc.gridwidth = GridBagConstraints.REMAINDER;

   559 

   560             entries = new JComboBox();

   561             entries.addActionListener(new ActionListener() {

   562                 public void actionPerformed(ActionEvent e) {

   563                     showEntry((Entry) entries.getSelectedItem());

   564                 }

   565             });

   566             fc.insets.bottom = 10;

   567             head.add(entries, fc);

   568             fc.insets.bottom = 0;

   569             head.add(new JLabel("check:"), lc);

   570             head.add(checkField = createTextField(80), fc);

   571             fc.fill = GridBagConstraints.NONE;

   572             head.add(setBackground(new JLabel("encl:"), enclColor), lc);

   573             head.add(enclPanel = new InfoPanel(), fc);

   574             head.add(setBackground(new JLabel("self:"), selfColor), lc);

   575             head.add(selfPanel = new InfoPanel(), fc);

   576             add(head, BorderLayout.NORTH);

   577 

   578             body = new JTextArea();

   579             body.setFont(Font.decode(Font.MONOSPACED));

   580             body.addCaretListener(new CaretListener() {

   581                 public void caretUpdate(CaretEvent e) {

   582                     int dot = e.getDot();

   583                     int mark = e.getMark();

   584                     if (dot == mark)

   585                         statusText.setText("dot: " + dot);

   586                     else

   587                         statusText.setText("dot: " + dot + ", mark:" + mark);

   588                 }

   589             });

   590             JScrollPane p = new JScrollPane(body,

   591                     JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,

   592                     JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

   593             p.setPreferredSize(new Dimension(640, 480));

   594             add(p, BorderLayout.CENTER);

   595 

   596             statusText = createTextField(80);

   597             add(statusText, BorderLayout.SOUTH);

   598 

   599             pack();

   600             setLocationRelativeTo(null); // centered on screen

   601             setVisible(true);

   602             setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

   603         }

   604 

   605         /** Show an entry that has been selected. */

   606         private void showEntry(Entry e) {

   607             try {

   608                 // update simple fields

   609                 setTitle(e.file.getName());

   610                 checkField.setText(e.check);

   611                 enclPanel.setInfo(e.encl);

   612                 selfPanel.setInfo(e.self);

   613                 // show file text with highlights

   614                 body.setText(e.file.getCharContent(true).toString());

   615                 Highlighter highlighter = body.getHighlighter();

   616                 highlighter.removeAllHighlights();

   617                 addHighlight(highlighter, e.encl, enclColor);

   618                 addHighlight(highlighter, e.self, selfColor);

   619                 scroll(body, getMinPos(enclPanel.info, selfPanel.info));

   620             } catch (IOException ex) {

   621                 body.setText("Cannot read " + e.file.getName() + ": " + e);

   622             }

   623         }

   624 

   625         /** Create a test field. */

   626         private JTextField createTextField(int width) {

   627             JTextField f = new JTextField(width);

   628             f.setEditable(false);

   629             f.setBorder(null);

   630             return f;

   631         }

   632 

   633         /** Add a highlighted region based on the positions in an Info object. */

   634         private void addHighlight(Highlighter h, Info info, Color c) {

   635             int start = info.start;

   636             int end = info.end;

   637             if (start == -1 && end == -1)

   638                 return;

   639             if (start == -1)

   640                 start = end;

   641             if (end == -1)

   642                 end = start;

   643             try {

   644                 h.addHighlight(info.start, info.end,

   645                         new DefaultHighlighter.DefaultHighlightPainter(c));

   646                 if (info.pos != -1) {

   647                     Color c2 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int)(.4f * 255)); // 40%

   648                     h.addHighlight(info.pos, info.pos + 1,

   649                         new DefaultHighlighter.DefaultHighlightPainter(c2));

   650                 }

   651             } catch (BadLocationException e) {

   652                 e.printStackTrace();

   653             }

   654         }

   655 

   656         /** Get the minimum valid position in a set of info objects. */

   657         private int getMinPos(Info... values) {

   658             int i = Integer.MAX_VALUE;

   659             for (Info info: values) {

   660                 if (info.start >= 0) i = Math.min(i, info.start);

   661                 if (info.pos   >= 0) i = Math.min(i, info.pos);

   662                 if (info.end   >= 0) i = Math.min(i, info.end);

   663             }

   664             return (i == Integer.MAX_VALUE) ? 0 : i;

   665         }

   666 

   667         /** Set the background on a component. */

   668         private JComponent setBackground(JComponent comp, Color c) {

   669             comp.setOpaque(true);

   670             comp.setBackground(c);

   671             return comp;

   672         }

   673 

   674         /** Scroll a text area to display a given position near the middle of the visible area. */

   675         private void scroll(final JTextArea t, final int pos) {

   676             // Using invokeLater appears to give text a chance to sort itself out

   677             // before the scroll happens; otherwise scrollRectToVisible doesn't work.

   678             // Maybe there's a better way to sync with the text...

   679             EventQueue.invokeLater(new Runnable() {

   680                 public void run() {

   681                     try {

   682                         Rectangle r = t.modelToView(pos);

   683                         JScrollPane p = (JScrollPane) SwingUtilities.getAncestorOfClass(JScrollPane.class, t);

   684                         r.y = Math.max(0, r.y - p.getHeight() * 2 / 5);

   685                         r.height += p.getHeight() * 4 / 5;

   686                         t.scrollRectToVisible(r);

   687                     } catch (BadLocationException ignore) {

   688                     }

   689                 }

   690             });

   691         }

   692 

   693         private JComboBox entries;

   694         private JTextField checkField;

   695         private InfoPanel enclPanel;

   696         private InfoPanel selfPanel;

   697         private JTextArea body;

   698         private JTextField statusText;

   699 

   700         private Color selfColor = new Color(0.f, 1.f, 0.f, 0.2f); // 20% green

   701         private Color enclColor = new Color(1.f, 0.f, 0.f, 0.2f); // 20% red

   702 

   703         /** Panel to display an Info object. */

   704         private class InfoPanel extends JPanel {

   705             InfoPanel() {

   706                 add(tagName = createTextField(20));

   707                 add(new JLabel("start:"));

   708                 add(addListener(start = createTextField(6)));

   709                 add(new JLabel("pos:"));

   710                 add(addListener(pos = createTextField(6)));

   711                 add(new JLabel("end:"));

   712                 add(addListener(end = createTextField(6)));

   713             }

   714 

   715             void setInfo(Info info) {

   716                 this.info = info;

   717                 tagName.setText(tagNames.get(info.tag));

   718                 start.setText(String.valueOf(info.start));

   719                 pos.setText(String.valueOf(info.pos));

   720                 end.setText(String.valueOf(info.end));

   721             }

   722 

   723             JTextField addListener(final JTextField f) {

   724                 f.addMouseListener(new MouseAdapter() {

   725                     @Override

   726                     public void mouseClicked(MouseEvent e) {

   727                         body.setCaretPosition(Integer.valueOf(f.getText()));

   728                         body.getCaret().setVisible(true);

   729                     }

   730                 });

   731                 return f;

   732             }

   733 

   734             Info info;

   735             JTextField tagName;

   736             JTextField start;

   737             JTextField pos;

   738             JTextField end;

   739         }

   740 

   741         /** Object to record information about an error to be displayed. */

   742         private class Entry {

   743             Entry(JavaFileObject file, String check, Info encl, Info self) {

   744                 this.file = file;

   745                 this.check = check;

   746                 this.encl = encl;

   747                 this.self= self;

   748             }

   749 

   750             @Override

   751             public String toString() {

   752                 return file.getName() + " " + check + " " + getMinPos(encl, self);

   753             }

   754 

   755             final JavaFileObject file;

   756             final String check;

   757             final Info encl;

   758             final Info self;

   759         }

   760     }

   761 }

   762