test/langtools/tools/javac/tree/TreePosTest.java
changeset 47216 71c04702a3d5
parent 44972 d2a28bbe4d44
child 51563 de411d537aae
equal deleted inserted replaced
47215:4ebc2e2fb97c 47216:71c04702a3d5
       
     1 /*
       
     2  * Copyright (c) 2010, 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
       
    20  * or visit www.oracle.com if you need additional information or have any
       
    21  * 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.EndPosTable;
       
    77 import com.sun.tools.javac.tree.JCTree;
       
    78 import com.sun.tools.javac.tree.JCTree.JCAnnotatedType;
       
    79 import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;
       
    80 import com.sun.tools.javac.tree.JCTree.JCNewClass;
       
    81 import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
       
    82 import com.sun.tools.javac.tree.TreeInfo;
       
    83 import com.sun.tools.javac.tree.TreeScanner;
       
    84 
       
    85 import static com.sun.tools.javac.tree.JCTree.Tag.*;
       
    86 import static com.sun.tools.javac.util.Position.NOPOS;
       
    87 
       
    88 /**
       
    89  * Utility and test program to check validity of tree positions for tree nodes.
       
    90  * The program can be run standalone, or as a jtreg test.  In standalone mode,
       
    91  * errors can be displayed in a gui viewer. For info on command line args,
       
    92  * run program with no args.
       
    93  *
       
    94  * <p>
       
    95  * jtreg: Note that by using the -r switch in the test description below, this test
       
    96  * will process all java files in the langtools/test directory, thus implicitly
       
    97  * covering any new language features that may be tested in this test suite.
       
    98  */
       
    99 
       
   100 /*
       
   101  * @test
       
   102  * @bug 6919889
       
   103  * @summary assorted position errors in compiler syntax trees
       
   104  * OLD: -q -r -ef ./tools/javac/typeAnnotations -ef ./tools/javap/typeAnnotations -et ANNOTATED_TYPE .
       
   105  * @modules java.desktop
       
   106  *          jdk.compiler/com.sun.tools.javac.api
       
   107  *          jdk.compiler/com.sun.tools.javac.code
       
   108  *          jdk.compiler/com.sun.tools.javac.file
       
   109  *          jdk.compiler/com.sun.tools.javac.tree
       
   110  *          jdk.compiler/com.sun.tools.javac.util
       
   111  * @run main TreePosTest -q -r .
       
   112  */
       
   113 public class TreePosTest {
       
   114     /**
       
   115      * Main entry point.
       
   116      * If test.src is set, program runs in jtreg mode, and will throw an Error
       
   117      * if any errors arise, otherwise System.exit will be used, unless the gui
       
   118      * viewer is being used. In jtreg mode, the default base directory for file
       
   119      * args is the value of ${test.src}. In jtreg mode, the -r option can be
       
   120      * given to change the default base directory to the root test directory.
       
   121      */
       
   122     public static void main(String... args) throws IOException {
       
   123         String testSrc = System.getProperty("test.src");
       
   124         File baseDir = (testSrc == null) ? null : new File(testSrc);
       
   125         boolean ok = new TreePosTest().run(baseDir, args);
       
   126         if (!ok) {
       
   127             if (testSrc != null)  // jtreg mode
       
   128                 throw new Error("failed");
       
   129             else
       
   130                 System.exit(1);
       
   131         }
       
   132     }
       
   133 
       
   134     /**
       
   135      * Run the program. A base directory can be provided for file arguments.
       
   136      * In jtreg mode, the -r option can be given to change the default base
       
   137      * directory to the test root directory. For other options, see usage().
       
   138      * @param baseDir base directory for any file arguments.
       
   139      * @param args command line args
       
   140      * @return true if successful or in gui mode
       
   141      */
       
   142     boolean run(File baseDir, String... args) throws IOException {
       
   143         try {
       
   144             if (args.length == 0) {
       
   145                 usage(System.out);
       
   146                 return true;
       
   147             }
       
   148 
       
   149             List<File> files = new ArrayList<File>();
       
   150             for (int i = 0; i < args.length; i++) {
       
   151                 String arg = args[i];
       
   152                 if (arg.equals("-encoding") && i + 1 < args.length)
       
   153                     encoding = args[++i];
       
   154                 else if (arg.equals("-gui"))
       
   155                     gui = true;
       
   156                 else if (arg.equals("-q"))
       
   157                     quiet = true;
       
   158                 else if (arg.equals("-v"))
       
   159                     verbose = true;
       
   160                 else if (arg.equals("-t") && i + 1 < args.length)
       
   161                     tags.add(args[++i]);
       
   162                 else if (arg.equals("-ef") && i + 1 < args.length)
       
   163                     excludeFiles.add(new File(baseDir, args[++i]));
       
   164                 else if (arg.equals("-et") && i + 1 < args.length)
       
   165                     excludeTags.add(args[++i]);
       
   166                 else if (arg.equals("-r")) {
       
   167                     if (excludeFiles.size() > 0)
       
   168                         throw new Error("-r must be used before -ef");
       
   169                     File d = baseDir;
       
   170                     while (!new File(d, "TEST.ROOT").exists()) {
       
   171                         d = d.getParentFile();
       
   172                         if (d == null)
       
   173                             throw new Error("cannot find TEST.ROOT");
       
   174                     }
       
   175                     baseDir = d;
       
   176                 }
       
   177                 else if (arg.startsWith("-"))
       
   178                     throw new Error("unknown option: " + arg);
       
   179                 else {
       
   180                     while (i < args.length)
       
   181                         files.add(new File(baseDir, args[i++]));
       
   182                 }
       
   183             }
       
   184 
       
   185             for (File file: files) {
       
   186                 if (file.exists())
       
   187                     test(file);
       
   188                 else
       
   189                     error("File not found: " + file);
       
   190             }
       
   191 
       
   192             if (fileCount != 1)
       
   193                 System.err.println(fileCount + " files read");
       
   194             if (errors > 0)
       
   195                 System.err.println(errors + " errors");
       
   196 
       
   197             return (gui || errors == 0);
       
   198         } finally {
       
   199             fm.close();
       
   200         }
       
   201     }
       
   202 
       
   203     /**
       
   204      * Print command line help.
       
   205      * @param out output stream
       
   206      */
       
   207     void usage(PrintStream out) {
       
   208         out.println("Usage:");
       
   209         out.println("  java TreePosTest options... files...");
       
   210         out.println("");
       
   211         out.println("where options include:");
       
   212         out.println("-gui      Display returns in a GUI viewer");
       
   213         out.println("-q        Quiet: don't report on inapplicable files");
       
   214         out.println("-v        Verbose: report on files as they are being read");
       
   215         out.println("-t tag    Limit checks to tree nodes with this tag");
       
   216         out.println("          Can be repeated if desired");
       
   217         out.println("-ef file  Exclude file or directory");
       
   218         out.println("-et tag   Exclude tree nodes with given tag name");
       
   219         out.println("");
       
   220         out.println("files may be directories or files");
       
   221         out.println("directories will be scanned recursively");
       
   222         out.println("non java files, or java files which cannot be parsed, will be ignored");
       
   223         out.println("");
       
   224     }
       
   225 
       
   226     /**
       
   227      * Test a file. If the file is a directory, it will be recursively scanned
       
   228      * for java files.
       
   229      * @param file the file or directory to test
       
   230      */
       
   231     void test(File file) {
       
   232         if (excludeFiles.contains(file)) {
       
   233             if (!quiet)
       
   234                 error("File " + file + " excluded");
       
   235             return;
       
   236         }
       
   237 
       
   238         if (file.isDirectory()) {
       
   239             for (File f: file.listFiles()) {
       
   240                 test(f);
       
   241             }
       
   242             return;
       
   243         }
       
   244 
       
   245         if (file.isFile() && file.getName().endsWith(".java")) {
       
   246             try {
       
   247                 if (verbose)
       
   248                     System.err.println(file);
       
   249                 fileCount++;
       
   250                 PosTester p = new PosTester();
       
   251                 p.test(read(file));
       
   252             } catch (ParseException e) {
       
   253                 if (!quiet) {
       
   254                     error("Error parsing " + file + "\n" + e.getMessage());
       
   255                 }
       
   256             } catch (IOException e) {
       
   257                 error("Error reading " + file + ": " + e);
       
   258             }
       
   259             return;
       
   260         }
       
   261 
       
   262         if (!quiet)
       
   263             error("File " + file + " ignored");
       
   264     }
       
   265 
       
   266     // See CR:  6982992 Tests CheckAttributedTree.java, JavacTreeScannerTest.java, and SourceTreeeScannerTest.java timeout
       
   267     StringWriter sw = new StringWriter();
       
   268     PrintWriter pw = new PrintWriter(sw);
       
   269     Reporter r = new Reporter(pw);
       
   270     JavacTool tool = JavacTool.create();
       
   271     StandardJavaFileManager fm = tool.getStandardFileManager(r, null, null);
       
   272 
       
   273     /**
       
   274      * Read a file.
       
   275      * @param file the file to be read
       
   276      * @return the tree for the content of the file
       
   277      * @throws IOException if any IO errors occur
       
   278      * @throws TreePosTest.ParseException if any errors occur while parsing the file
       
   279      */
       
   280     JCCompilationUnit read(File file) throws IOException, ParseException {
       
   281         JavacTool tool = JavacTool.create();
       
   282         r.errors = 0;
       
   283         Iterable<? extends JavaFileObject> files = fm.getJavaFileObjects(file);
       
   284         JavacTask task = tool.getTask(pw, fm, r, List.of("-proc:none"), null, files);
       
   285         Iterable<? extends CompilationUnitTree> trees = task.parse();
       
   286         pw.flush();
       
   287         if (r.errors > 0)
       
   288             throw new ParseException(sw.toString());
       
   289         Iterator<? extends CompilationUnitTree> iter = trees.iterator();
       
   290         if (!iter.hasNext())
       
   291             throw new Error("no trees found");
       
   292         JCCompilationUnit t = (JCCompilationUnit) iter.next();
       
   293         if (iter.hasNext())
       
   294             throw new Error("too many trees found");
       
   295         return t;
       
   296     }
       
   297 
       
   298     /**
       
   299      * Report an error. When the program is complete, the program will either
       
   300      * exit or throw an Error if any errors have been reported.
       
   301      * @param msg the error message
       
   302      */
       
   303     void error(String msg) {
       
   304         System.err.println(msg);
       
   305         errors++;
       
   306     }
       
   307 
       
   308     /**
       
   309      * Names for tree tags.
       
   310      */
       
   311     private static String getTagName(JCTree.Tag tag) {
       
   312         String name = tag.name();
       
   313         return (name == null) ? "??" : name;
       
   314     }
       
   315 
       
   316     /** Number of files that have been analyzed. */
       
   317     int fileCount;
       
   318     /** Number of errors reported. */
       
   319     int errors;
       
   320     /** Flag: don't report irrelevant files. */
       
   321     boolean quiet;
       
   322     /** Flag: report files as they are processed. */
       
   323     boolean verbose;
       
   324     /** Flag: show errors in GUI viewer. */
       
   325     boolean gui;
       
   326     /** Option: encoding for test files. */
       
   327     String encoding;
       
   328     /** The GUI viewer for errors. */
       
   329     Viewer viewer;
       
   330     /** The set of tags for tree nodes to be analyzed; if empty, all tree nodes
       
   331      * are analyzed. */
       
   332     Set<String> tags = new HashSet<String>();
       
   333     /** Set of files and directories to be excluded from analysis. */
       
   334     Set<File> excludeFiles = new HashSet<File>();
       
   335     /** Set of tag names to be excluded from analysis. */
       
   336     Set<String> excludeTags = new HashSet<String>();
       
   337 
       
   338     /**
       
   339      * Main class for testing assertions concerning tree positions for tree nodes.
       
   340      */
       
   341     private class PosTester extends TreeScanner {
       
   342         void test(JCCompilationUnit tree) {
       
   343             sourcefile = tree.sourcefile;
       
   344             endPosTable = tree.endPositions;
       
   345             encl = new Info();
       
   346             tree.accept(this);
       
   347         }
       
   348 
       
   349         @Override
       
   350         public void scan(JCTree tree) {
       
   351             if (tree == null)
       
   352                 return;
       
   353 
       
   354             Info self = new Info(tree, endPosTable);
       
   355             if (check(encl, self)) {
       
   356                 // Modifiers nodes are present throughout the tree even where
       
   357                 // there is no corresponding source text.
       
   358                 // Redundant semicolons in a class definition can cause empty
       
   359                 // initializer blocks with no positions.
       
   360                 if ((self.tag == MODIFIERS || self.tag == BLOCK)
       
   361                         && self.pos == NOPOS) {
       
   362                     // If pos is NOPOS, so should be the start and end positions
       
   363                     check("start == NOPOS", encl, self, self.start == NOPOS);
       
   364                     check("end == NOPOS", encl, self, self.end == NOPOS);
       
   365                 } else {
       
   366                     // For this node, start , pos, and endpos should be all defined
       
   367                     check("start != NOPOS", encl, self, self.start != NOPOS);
       
   368                     check("pos != NOPOS", encl, self, self.pos != NOPOS);
       
   369                     check("end != NOPOS", encl, self, self.end != NOPOS);
       
   370                     // The following should normally be ordered
       
   371                     // encl.start <= start <= pos <= end <= encl.end
       
   372                     // In addition, the position of the enclosing node should be
       
   373                     // within this node.
       
   374                     // The primary exceptions are for array type nodes, because of the
       
   375                     // need to support legacy syntax:
       
   376                     //    e.g.    int a[];    int[] b[];    int f()[] { return null; }
       
   377                     // and because of inconsistent nesting of left and right of
       
   378                     // array declarations:
       
   379                     //    e.g.    int[][] a = new int[2][];
       
   380                     if (!(encl.tag == REFERENCE && self.tag == ANNOTATED_TYPE)) {
       
   381                     check("encl.start <= start", encl, self, encl.start <= self.start);
       
   382                     }
       
   383                     check("start <= pos", encl, self, self.start <= self.pos);
       
   384                     if (!( (self.tag == TYPEARRAY ||
       
   385                             isAnnotatedArray(self.tree))
       
   386                             && (encl.tag == VARDEF ||
       
   387                                 encl.tag == METHODDEF ||
       
   388                                 encl.tag == TYPEARRAY ||
       
   389                                 isAnnotatedArray(encl.tree))
       
   390                            ||
       
   391                             encl.tag == ANNOTATED_TYPE && self.tag == SELECT
       
   392                            ||
       
   393                             encl.tag == REFERENCE && self.tag == ANNOTATED_TYPE
       
   394                          )) {
       
   395                         check("encl.pos <= start || end <= encl.pos",
       
   396                                 encl, self, encl.pos <= self.start || self.end <= encl.pos);
       
   397                     }
       
   398                     check("pos <= end", encl, self, self.pos <= self.end);
       
   399                     if (!( (self.tag == TYPEARRAY || isAnnotatedArray(self.tree)) &&
       
   400                             (encl.tag == TYPEARRAY || isAnnotatedArray(encl.tree))
       
   401                            ||
       
   402                             encl.tag == MODIFIERS && self.tag == ANNOTATION
       
   403                          ) ) {
       
   404                         check("end <= encl.end", encl, self, self.end <= encl.end);
       
   405                     }
       
   406                 }
       
   407             }
       
   408 
       
   409             Info prevEncl = encl;
       
   410             encl = self;
       
   411             tree.accept(this);
       
   412             encl = prevEncl;
       
   413         }
       
   414 
       
   415         private boolean isAnnotatedArray(JCTree tree) {
       
   416             return tree.hasTag(ANNOTATED_TYPE) &&
       
   417                             ((JCAnnotatedType)tree).underlyingType.hasTag(TYPEARRAY);
       
   418         }
       
   419 
       
   420         @Override
       
   421         public void visitVarDef(JCVariableDecl tree) {
       
   422             // enum member declarations are desugared in the parser and have
       
   423             // ill-defined semantics for tree positions, so for now, we
       
   424             // skip the synthesized bits and just check parts which came from
       
   425             // the original source text
       
   426             if ((tree.mods.flags & Flags.ENUM) != 0) {
       
   427                 scan(tree.mods);
       
   428                 if (tree.init != null) {
       
   429                     if (tree.init.hasTag(NEWCLASS)) {
       
   430                         JCNewClass init = (JCNewClass) tree.init;
       
   431                         if (init.args != null && init.args.nonEmpty()) {
       
   432                             scan(init.args);
       
   433                         }
       
   434                         if (init.def != null && init.def.defs != null) {
       
   435                             scan(init.def.defs);
       
   436                         }
       
   437                     }
       
   438                 }
       
   439             } else
       
   440                 super.visitVarDef(tree);
       
   441         }
       
   442 
       
   443         boolean check(Info encl, Info self) {
       
   444             if (excludeTags.size() > 0) {
       
   445                 if (encl != null && excludeTags.contains(getTagName(encl.tag))
       
   446                         || excludeTags.contains(getTagName(self.tag)))
       
   447                     return false;
       
   448             }
       
   449             return tags.size() == 0 || tags.contains(getTagName(self.tag));
       
   450         }
       
   451 
       
   452         void check(String label, Info encl, Info self, boolean ok) {
       
   453             if (!ok) {
       
   454                 if (gui) {
       
   455                     if (viewer == null)
       
   456                         viewer = new Viewer();
       
   457                     viewer.addEntry(sourcefile, label, encl, self);
       
   458                 }
       
   459 
       
   460                 String s = "encl: " + encl.tree.toString() +
       
   461                         "  this: " + self.tree.toString();
       
   462                 String msg = sourcefile.getName() + ": " + label + ": " +
       
   463                         "encl:" + encl + " this:" + self + "\n" +
       
   464                         s.substring(0, Math.min(80, s.length())).replaceAll("[\r\n]+", " ");
       
   465                 error(msg);
       
   466             }
       
   467         }
       
   468 
       
   469         JavaFileObject sourcefile;
       
   470         EndPosTable endPosTable;
       
   471         Info encl;
       
   472 
       
   473     }
       
   474 
       
   475     /**
       
   476      * Utility class providing easy access to position and other info for a tree node.
       
   477      */
       
   478     private class Info {
       
   479         Info() {
       
   480             tree = null;
       
   481             tag = ERRONEOUS;
       
   482             start = 0;
       
   483             pos = 0;
       
   484             end = Integer.MAX_VALUE;
       
   485         }
       
   486 
       
   487         Info(JCTree tree, EndPosTable endPosTable) {
       
   488             this.tree = tree;
       
   489             tag = tree.getTag();
       
   490             start = TreeInfo.getStartPos(tree);
       
   491             pos = tree.pos;
       
   492             end = TreeInfo.getEndPos(tree, endPosTable);
       
   493         }
       
   494 
       
   495         @Override
       
   496         public String toString() {
       
   497             return getTagName(tree.getTag()) + "[start:" + start + ",pos:" + pos + ",end:" + end + "]";
       
   498         }
       
   499 
       
   500         final JCTree tree;
       
   501         final JCTree.Tag tag;
       
   502         final int start;
       
   503         final int pos;
       
   504         final int end;
       
   505     }
       
   506 
       
   507     /**
       
   508      * Thrown when errors are found parsing a java file.
       
   509      */
       
   510     private static class ParseException extends Exception {
       
   511         ParseException(String msg) {
       
   512             super(msg);
       
   513         }
       
   514     }
       
   515 
       
   516     /**
       
   517      * DiagnosticListener to report diagnostics and count any errors that occur.
       
   518      */
       
   519     private static class Reporter implements DiagnosticListener<JavaFileObject> {
       
   520         Reporter(PrintWriter out) {
       
   521             this.out = out;
       
   522         }
       
   523 
       
   524         public void report(Diagnostic<? extends JavaFileObject> diagnostic) {
       
   525             out.println(diagnostic);
       
   526             switch (diagnostic.getKind()) {
       
   527                 case ERROR:
       
   528                     errors++;
       
   529             }
       
   530         }
       
   531         int errors;
       
   532         PrintWriter out;
       
   533     }
       
   534 
       
   535     /**
       
   536      * GUI viewer for issues found by TreePosTester. The viewer provides a drop
       
   537      * down list for selecting error conditions, a header area providing details
       
   538      * about an error, and a text area with the ranges of text highlighted as
       
   539      * appropriate.
       
   540      */
       
   541     private class Viewer extends JFrame {
       
   542         /**
       
   543          * Create a viewer.
       
   544          */
       
   545         Viewer() {
       
   546             initGUI();
       
   547         }
       
   548 
       
   549         /**
       
   550          * Add another entry to the list of errors.
       
   551          * @param file The file containing the error
       
   552          * @param check The condition that was being tested, and which failed
       
   553          * @param encl the enclosing tree node
       
   554          * @param self the tree node containing the error
       
   555          */
       
   556         void addEntry(JavaFileObject file, String check, Info encl, Info self) {
       
   557             Entry e = new Entry(file, check, encl, self);
       
   558             DefaultComboBoxModel m = (DefaultComboBoxModel) entries.getModel();
       
   559             m.addElement(e);
       
   560             if (m.getSize() == 1)
       
   561                 entries.setSelectedItem(e);
       
   562         }
       
   563 
       
   564         /**
       
   565          * Initialize the GUI window.
       
   566          */
       
   567         private void initGUI() {
       
   568             JPanel head = new JPanel(new GridBagLayout());
       
   569             GridBagConstraints lc = new GridBagConstraints();
       
   570             GridBagConstraints fc = new GridBagConstraints();
       
   571             fc.anchor = GridBagConstraints.WEST;
       
   572             fc.fill = GridBagConstraints.HORIZONTAL;
       
   573             fc.gridwidth = GridBagConstraints.REMAINDER;
       
   574 
       
   575             entries = new JComboBox();
       
   576             entries.addActionListener(new ActionListener() {
       
   577                 public void actionPerformed(ActionEvent e) {
       
   578                     showEntry((Entry) entries.getSelectedItem());
       
   579                 }
       
   580             });
       
   581             fc.insets.bottom = 10;
       
   582             head.add(entries, fc);
       
   583             fc.insets.bottom = 0;
       
   584             head.add(new JLabel("check:"), lc);
       
   585             head.add(checkField = createTextField(80), fc);
       
   586             fc.fill = GridBagConstraints.NONE;
       
   587             head.add(setBackground(new JLabel("encl:"), enclColor), lc);
       
   588             head.add(enclPanel = new InfoPanel(), fc);
       
   589             head.add(setBackground(new JLabel("self:"), selfColor), lc);
       
   590             head.add(selfPanel = new InfoPanel(), fc);
       
   591             add(head, BorderLayout.NORTH);
       
   592 
       
   593             body = new JTextArea();
       
   594             body.setFont(Font.decode(Font.MONOSPACED));
       
   595             body.addCaretListener(new CaretListener() {
       
   596                 public void caretUpdate(CaretEvent e) {
       
   597                     int dot = e.getDot();
       
   598                     int mark = e.getMark();
       
   599                     if (dot == mark)
       
   600                         statusText.setText("dot: " + dot);
       
   601                     else
       
   602                         statusText.setText("dot: " + dot + ", mark:" + mark);
       
   603                 }
       
   604             });
       
   605             JScrollPane p = new JScrollPane(body,
       
   606                     JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
       
   607                     JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
       
   608             p.setPreferredSize(new Dimension(640, 480));
       
   609             add(p, BorderLayout.CENTER);
       
   610 
       
   611             statusText = createTextField(80);
       
   612             add(statusText, BorderLayout.SOUTH);
       
   613 
       
   614             pack();
       
   615             setLocationRelativeTo(null); // centered on screen
       
   616             setVisible(true);
       
   617             setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       
   618         }
       
   619 
       
   620         /** Show an entry that has been selected. */
       
   621         private void showEntry(Entry e) {
       
   622             try {
       
   623                 // update simple fields
       
   624                 setTitle(e.file.getName());
       
   625                 checkField.setText(e.check);
       
   626                 enclPanel.setInfo(e.encl);
       
   627                 selfPanel.setInfo(e.self);
       
   628                 // show file text with highlights
       
   629                 body.setText(e.file.getCharContent(true).toString());
       
   630                 Highlighter highlighter = body.getHighlighter();
       
   631                 highlighter.removeAllHighlights();
       
   632                 addHighlight(highlighter, e.encl, enclColor);
       
   633                 addHighlight(highlighter, e.self, selfColor);
       
   634                 scroll(body, getMinPos(enclPanel.info, selfPanel.info));
       
   635             } catch (IOException ex) {
       
   636                 body.setText("Cannot read " + e.file.getName() + ": " + e);
       
   637             }
       
   638         }
       
   639 
       
   640         /** Create a test field. */
       
   641         private JTextField createTextField(int width) {
       
   642             JTextField f = new JTextField(width);
       
   643             f.setEditable(false);
       
   644             f.setBorder(null);
       
   645             return f;
       
   646         }
       
   647 
       
   648         /** Add a highlighted region based on the positions in an Info object. */
       
   649         private void addHighlight(Highlighter h, Info info, Color c) {
       
   650             int start = info.start;
       
   651             int end = info.end;
       
   652             if (start == -1 && end == -1)
       
   653                 return;
       
   654             if (start == -1)
       
   655                 start = end;
       
   656             if (end == -1)
       
   657                 end = start;
       
   658             try {
       
   659                 h.addHighlight(info.start, info.end,
       
   660                         new DefaultHighlighter.DefaultHighlightPainter(c));
       
   661                 if (info.pos != -1) {
       
   662                     Color c2 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int)(.4f * 255)); // 40%
       
   663                     h.addHighlight(info.pos, info.pos + 1,
       
   664                         new DefaultHighlighter.DefaultHighlightPainter(c2));
       
   665                 }
       
   666             } catch (BadLocationException e) {
       
   667                 e.printStackTrace();
       
   668             }
       
   669         }
       
   670 
       
   671         /** Get the minimum valid position in a set of info objects. */
       
   672         private int getMinPos(Info... values) {
       
   673             int i = Integer.MAX_VALUE;
       
   674             for (Info info: values) {
       
   675                 if (info.start >= 0) i = Math.min(i, info.start);
       
   676                 if (info.pos   >= 0) i = Math.min(i, info.pos);
       
   677                 if (info.end   >= 0) i = Math.min(i, info.end);
       
   678             }
       
   679             return (i == Integer.MAX_VALUE) ? 0 : i;
       
   680         }
       
   681 
       
   682         /** Set the background on a component. */
       
   683         private JComponent setBackground(JComponent comp, Color c) {
       
   684             comp.setOpaque(true);
       
   685             comp.setBackground(c);
       
   686             return comp;
       
   687         }
       
   688 
       
   689         /** Scroll a text area to display a given position near the middle of the visible area. */
       
   690         private void scroll(final JTextArea t, final int pos) {
       
   691             // Using invokeLater appears to give text a chance to sort itself out
       
   692             // before the scroll happens; otherwise scrollRectToVisible doesn't work.
       
   693             // Maybe there's a better way to sync with the text...
       
   694             EventQueue.invokeLater(new Runnable() {
       
   695                 public void run() {
       
   696                     try {
       
   697                         Rectangle r = t.modelToView(pos);
       
   698                         JScrollPane p = (JScrollPane) SwingUtilities.getAncestorOfClass(JScrollPane.class, t);
       
   699                         r.y = Math.max(0, r.y - p.getHeight() * 2 / 5);
       
   700                         r.height += p.getHeight() * 4 / 5;
       
   701                         t.scrollRectToVisible(r);
       
   702                     } catch (BadLocationException ignore) {
       
   703                     }
       
   704                 }
       
   705             });
       
   706         }
       
   707 
       
   708         private JComboBox entries;
       
   709         private JTextField checkField;
       
   710         private InfoPanel enclPanel;
       
   711         private InfoPanel selfPanel;
       
   712         private JTextArea body;
       
   713         private JTextField statusText;
       
   714 
       
   715         private Color selfColor = new Color(0.f, 1.f, 0.f, 0.2f); // 20% green
       
   716         private Color enclColor = new Color(1.f, 0.f, 0.f, 0.2f); // 20% red
       
   717 
       
   718         /** Panel to display an Info object. */
       
   719         private class InfoPanel extends JPanel {
       
   720             InfoPanel() {
       
   721                 add(tagName = createTextField(20));
       
   722                 add(new JLabel("start:"));
       
   723                 add(addListener(start = createTextField(6)));
       
   724                 add(new JLabel("pos:"));
       
   725                 add(addListener(pos = createTextField(6)));
       
   726                 add(new JLabel("end:"));
       
   727                 add(addListener(end = createTextField(6)));
       
   728             }
       
   729 
       
   730             void setInfo(Info info) {
       
   731                 this.info = info;
       
   732                 tagName.setText(getTagName(info.tag));
       
   733                 start.setText(String.valueOf(info.start));
       
   734                 pos.setText(String.valueOf(info.pos));
       
   735                 end.setText(String.valueOf(info.end));
       
   736             }
       
   737 
       
   738             JTextField addListener(final JTextField f) {
       
   739                 f.addMouseListener(new MouseAdapter() {
       
   740                     @Override
       
   741                     public void mouseClicked(MouseEvent e) {
       
   742                         body.setCaretPosition(Integer.valueOf(f.getText()));
       
   743                         body.getCaret().setVisible(true);
       
   744                     }
       
   745                 });
       
   746                 return f;
       
   747             }
       
   748 
       
   749             Info info;
       
   750             JTextField tagName;
       
   751             JTextField start;
       
   752             JTextField pos;
       
   753             JTextField end;
       
   754         }
       
   755 
       
   756         /** Object to record information about an error to be displayed. */
       
   757         private class Entry {
       
   758             Entry(JavaFileObject file, String check, Info encl, Info self) {
       
   759                 this.file = file;
       
   760                 this.check = check;
       
   761                 this.encl = encl;
       
   762                 this.self= self;
       
   763             }
       
   764 
       
   765             @Override
       
   766             public String toString() {
       
   767                 return file.getName() + " " + check + " " + getMinPos(encl, self);
       
   768             }
       
   769 
       
   770             final JavaFileObject file;
       
   771             final String check;
       
   772             final Info encl;
       
   773             final Info self;
       
   774         }
       
   775     }
       
   776 }
       
   777