javacompiler.java

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    public boolean verbose;

    /** Emit plain Java source files rather than class files.
     */
    public boolean sourceOutput;

    /** Emit stub source files rather than class files.
     */
    public boolean stubOutput;

    /** Generate attributed parse tree only.
     */
    public boolean attrParseOnly;

    /** Switch: relax some constraints for producing the jsr14 prototype.
     */
    boolean relax;

    /** Debug switch: Emit Java sources after inner class flattening.
     */
    public boolean printFlat;

    /** The encoding to be used for source input.
     */
    public String encoding;

    /** Generate code with the LineNumberTable attribute for debugging
     */
    public boolean lineDebugInfo;

    /** Switch: should we store the ending positions?
     */
    public boolean genEndPos;

    /** Switch: should we debug ignored exceptions
     */
    protected boolean devVerbose;

    /** Switch: should we (annotation) process packages as well
     */
    protected boolean processPcks;

    /** Switch: is annotation processing requested explitly via
     * CompilationTask.setProcessors?
     */
    protected boolean explicitAnnotationProcessingRequested = false;

    /**
     * The policy for the order in which to perform the compilation
     */
    protected CompilePolicy compilePolicy;
    
    /**
     * The policy for what to do with implicitly read source files
     */
    protected ImplicitSourcePolicy implicitSourcePolicy;

    /**
     * Report activity related to compilePolicy
     */
    public boolean verboseCompilePolicy;

    /** A queue of all as yet unattributed classes.
     */
    public Todo todo;

    private Set<Env<AttrContext>> deferredSugar = new HashSet<Env<AttrContext>>();

    /** The set of currently compiled inputfiles, needed to ensure
     *  we don't accidentally overwrite an input file when -s is set.
     *  initialized by `compile'.
     */
    protected Set<JavaFileObject> inputFiles = new HashSet<JavaFileObject>();

    /** The number of errors reported so far.
     */
    public int errorCount() {
        if (delegateCompiler != null && delegateCompiler != this)
            return delegateCompiler.errorCount();
        else
            return log.nerrors;
    }

    protected final <T> List<T> stopIfError(ListBuffer<T> listBuffer) {
        if (errorCount() == 0)
            return listBuffer.toList();
        else
            return List.nil();
    }

    protected final <T> List<T> stopIfError(List<T> list) {
        if (errorCount() == 0)
            return list;
        else
            return List.nil();
    }

    /** The number of warnings reported so far.
     */
    public int warningCount() {
        if (delegateCompiler != null && delegateCompiler != this)
            return delegateCompiler.warningCount();
        else
            return log.nwarnings;
    }
    
    /** Whether or not any parse errors have occurred.
     */
    public boolean parseErrors() {
	return parseErrors;
    }

    protected Scanner.Factory getScannerFactory() {
        return Scanner.Factory.instance(context);
    }

    /** Try to open input stream with given name.
     *  Report an error if this fails.
     *  @param filename   The file name of the input stream to be opened.
     */
    public CharSequence readSource(JavaFileObject filename) {
        try {
            inputFiles.add(filename);
            return filename.getCharContent(false);
        } catch (IOException e) {
            log.error("error.reading.file", filename, e.getLocalizedMessage());
            return null;
        }
    }

    /** Parse contents of input stream.
     *  @param filename     The name of the file from which input stream comes.
     *  @param input        The input stream to be parsed.
     */
    protected JCCompilationUnit parse(JavaFileObject filename, CharSequence content) {
        long msec = now();
        JCCompilationUnit tree = make.TopLevel(List.<JCTree.JCAnnotation>nil(),
                                      null, List.<JCTree>nil());
        if (content != null) {
            if (verbose) {
                printVerbose("parsing.started", filename);
            }
            if (taskListener != null) {
                TaskEvent e = new TaskEvent(TaskEvent.Kind.PARSE, filename);
                taskListener.started(e);
            }
	    int initialErrorCount = log.nerrors;
            Scanner scanner = getScannerFactory().newScanner(content);
            Parser parser = parserFactory.newParser(scanner, keepComments(), genEndPos);
            tree = parser.compilationUnit();
	    parseErrors |= (log.nerrors > initialErrorCount);
            if (lineDebugInfo) {
                tree.lineMap = scanner.getLineMap();
            }
            if (verbose) {
                printVerbose("parsing.done", Long.toString(elapsed(msec)));
            }
        }

        tree.sourcefile = filename;

        if (content != null && taskListener != null) {
            TaskEvent e = new TaskEvent(TaskEvent.Kind.PARSE, tree);
            taskListener.finished(e);
        }

        return tree;
    }
    // where
        public boolean keepComments = false;
        protected boolean keepComments() {
            return keepComments || sourceOutput || stubOutput;
        }


    /** Parse contents of file.
     *  @param filename     The name of the file to be parsed.
     */
    @Deprecated
    public JCTree.JCCompilationUnit parse(String filename) throws IOException {
	JavacFileManager fm = (JavacFileManager)fileManager;
        return parse(fm.getJavaFileObjectsFromStrings(List.of(filename)).iterator().next());
    }

    /** Parse contents of file.
     *  @param filename     The name of the file to be parsed.
     */
    public JCTree.JCCompilationUnit parse(JavaFileObject filename) {
        JavaFileObject prev = log.useSource(filename);
        try {
            JCTree.JCCompilationUnit t = parse(filename, readSource(filename));
            if (t.endPositions != null)
                log.setEndPosTable(filename, t.endPositions);
            return t;
        } finally {
            log.useSource(prev);
        }
    }

    /** Resolve an identifier.
     * @param name      The identifier to resolve
     */
    public Symbol resolveIdent(String name) {
        if (name.equals(""))
            return syms.errSymbol;
        JavaFileObject prev = log.useSource(null);
        try {
            JCExpression tree = null;
            for (String s : name.split("\\.", -1)) {
                if (!SourceVersion.isIdentifier(s)) // TODO: check for keywords
                    return syms.errSymbol;
                tree = (tree == null) ? make.Ident(names.fromString(s))
                                      : make.Select(tree, names.fromString(s));
            }
            JCCompilationUnit toplevel =
                make.TopLevel(List.<JCTree.JCAnnotation>nil(), null, List.<JCTree>nil());
            toplevel.packge = syms.unnamedPackage;
            return attr.attribIdent(tree, toplevel);
        } finally {
            log.useSource(prev);
        }
    }

    /** Emit plain Java source for a class.
     *  @param env    The attribution environment of the outermost class
     *                containing this class.
     *  @param cdef   The class definition to be printed.
     */
    JavaFileObject printSource(Env<AttrContext> env, JCClassDecl cdef) throws IOException {
        JavaFileObject outFile
            = fileManager.getJavaFileForOutput(CLASS_OUTPUT,
					       cdef.sym.flatname.toString(),
					       JavaFileObject.Kind.SOURCE,
					       null);
        if (inputFiles.contains(outFile)) {
            log.error(cdef.pos(), "source.cant.overwrite.input.file", outFile);
            return null;
        } else {
            BufferedWriter out = new BufferedWriter(outFile.openWriter());
            try {
                new Pretty(out, true).printUnit(env.toplevel, cdef);
                if (verbose)
                    printVerbose("wrote.file", outFile);
            } finally {
                out.close();
            }
            return outFile;
        }
    }

    /** Generate code and emit a class file for a given class
     *  @param env    The attribution environment of the outermost class
     *                containing this class.
     *  @param cdef   The class definition from which code is generated.
     */
    JavaFileObject genCode(Env<AttrContext> env, JCClassDecl cdef) throws IOException {
        try {
            if (gen.genClass(env, cdef)) 
                return writer.writeClass(cdef.sym);
        } catch (ClassWriter.PoolOverflow ex) {
            log.error(cdef.pos(), "limit.pool");
        } catch (ClassWriter.StringOverflow ex) {
            log.error(cdef.pos(), "limit.string.overflow",
                      ex.value.substring(0, 20));
        } catch (CompletionFailure ex) {
            chk.completionError(cdef.pos(), ex);
        }
        return null;
    }

    /** Complete compiling a source file that has been accessed
     *  by the class file reader.
     *  @param c          The class the source file of which needs to be compiled.
     *  @param filename   The name of the source file.
     *  @param f          An input stream that reads the source file.
     */
    public void complete(ClassSymbol c) throws CompletionFailure {
//      System.err.println("completing " + c);//DEBUG
        if (completionFailureName == c.fullname) {
            throw new CompletionFailure(c, "user-selected completion failure by class name");
        }
        JCCompilationUnit tree;
        JavaFileObject filename = c.classfile;
        JavaFileObject prev = log.useSource(filename);

        try {
            tree = parse(filename, filename.getCharContent(false));
        } catch (IOException e) {
            log.error("error.reading.file", filename, e);
            tree = make.TopLevel(List.<JCTree.JCAnnotation>nil(), null, List.<JCTree>nil());
        } finally {
            log.useSource(prev);
        }

        if (taskListener != null) {
            TaskEvent e = new TaskEvent(TaskEvent.Kind.ENTER, tree);
            taskListener.started(e);
        }

        enter.complete(List.of(tree), c);

        if (taskListener != null) {
            TaskEvent e = new TaskEvent(TaskEvent.Kind.ENTER, tree);
            taskListener.finished(e);
        }

        if (enter.getEnv(c) == null) {
            boolean isPkgInfo =
                tree.sourcefile.isNameCompatible("package-info",
                                                 JavaFileObject.Kind.SOURCE);
            if (isPkgInfo) {
                if (enter.getEnv(tree.packge) == null) {
                    String msg
                        = log.getLocalizedString("file.does.not.contain.package",
                                                 c.location());
                    throw new ClassReader.BadClassFile(c, filename, msg);
                }
            } else {
                throw new
                    ClassReader.BadClassFile(c, filename, log.
                                             getLocalizedString("file.doesnt.contain.class",
                                                                c.fullname));
            }
        }
        
        implicitSourceFilesRead = true;
    }

    /** Track when the JavaCompiler has been used to compile something. */
    private boolean hasBeenUsed = false;
    private long start_msec = 0;
    public long elapsed_msec = 0;

    /** Track whether any errors occurred while parsing source text. */
    private boolean parseErrors = false;

    public void compile(List<JavaFileObject> sourceFileObject)
        throws Throwable {
        compile(sourceFileObject, List.<String>nil(), null);
    }

    /**
     * Main method: compile a list of files, return all compiled classes
     *
     * @param sourceFileObjects file objects to be compiled
     * @param classnames class names to process for annotations
     * @param processors user provided annotation processors to bypass
     * discovery, {@code null} means that no processors were provided
     */
    public void compile(List<JavaFileObject> sourceFileObjects,
                        List<String> classnames,
			Iterable<? extends Processor> processors)
        throws IOException // TODO: temp, from JavacProcessingEnvironment
    {
        if (processors != null && processors.iterator().hasNext())
            explicitAnnotationProcessingRequested = true;
        // as a JavaCompiler can only be used once, throw an exception if
        // it has been used before.
        if (hasBeenUsed)
	    throw new AssertionError("attempt to reuse JavaCompiler");
        hasBeenUsed = true;

        start_msec = now();
        try {
            initProcessAnnotations(processors);

            // These method calls must be chained to avoid memory leaks
            delegateCompiler = processAnnotations(enterTrees(stopIfError(parseFiles(sourceFileObjects))),
                                                  classnames);

            delegateCompiler.compile2();
	    delegateCompiler.close();
	    elapsed_msec = delegateCompiler.elapsed_msec;