import com.sun.tools.javac.parser.DocCommentScanner; //导入依赖的package包/类
/**
 * Check if we should process annotations.
 * If so, and if no scanner is yet registered, then set up the DocCommentScanner
 * to catch doc comments, and set keepComments so the parser records them in
 * the compilation unit.
 *
 * @param processors user provided annotation processors to bypass
 * discovery, {@code null} means that no processors were provided
 */
public void initProcessAnnotations(Iterable<? extends Processor> processors) {
    // Process annotations if processing is not disabled and there
    // is at least one Processor available.
    Options options = Options.instance(context);
    if (options.get("-proc:none") != null) {
        processAnnotations = false;
    } else if (procEnvImpl == null) {
        procEnvImpl = new JavacProcessingEnvironment(context, processors);
        processAnnotations = procEnvImpl.atLeastOneProcessor();

        if (processAnnotations) {
            if (context.get(Scanner.Factory.scannerFactoryKey) == null)
                DocCommentScanner.Factory.preRegister(context);
            options.put("save-parameter-names", "save-parameter-names");
            reader.saveParameterNames = true;
            keepComments = true;
            if (taskListener != null)
                taskListener.started(new TaskEvent(TaskEvent.Kind.ANNOTATION_PROCESSING));


        } else { // free resources
            procEnvImpl.close();
        }
    }
}
 

import com.sun.tools.javac.parser.DocCommentScanner; //导入依赖的package包/类
/**
 *  Construct a new javadoc tool.
 */
public static JavadocTool make0(Context context) {
    Messager messager = null;
    try {
        // force the use of Javadoc's class reader
        JavadocClassReader.preRegister(context);

        // force the use of Javadoc's own enter phase
        JavadocEnter.preRegister(context);

        // force the use of Javadoc's own member enter phase
        JavadocMemberEnter.preRegister(context);

        // force the use of Javadoc's own todo phase
        JavadocTodo.preRegister(context);

        // force the use of Messager as a Log
        messager = Messager.instance0(context);

        // force the use of the scanner that captures Javadoc comments
        DocCommentScanner.Factory.preRegister(context);

        return new JavadocTool(context);
    } catch (CompletionFailure ex) {
        messager.error(Position.NOPOS, ex.getMessage());
        return null;
    }
}
 

import com.sun.tools.javac.parser.DocCommentScanner; //导入依赖的package包/类
private static Context preRegister(Context context) {
    Bark.preRegister(context);

    // force the use of the scanner that captures Javadoc comments
    DocCommentScanner.Factory.preRegister(context);

    if (context.get(JavaFileManager.class) == null)
        JavacFileManager.preRegister(context);

    return context;
}
 

import com.sun.tools.javac.parser.DocCommentScanner; //导入依赖的package包/类
/**
 * Check if we should process annotations.
 * If so, and if no scanner is yet registered, then set up the DocCommentScanner
 * to catch doc comments, and set keepComments so the parser records them in
 * the compilation unit.
 *
 * @param processors user provided annotation processors to bypass
 * discovery, {@code null} means that no processors were provided
 */
public void initProcessAnnotations(Iterable<? extends Processor> processors)
            throws IOException {
    // Process annotations if processing is not disabled and there
    // is at least one Processor available.
    Options options = Options.instance(context);
    if (options.get("-proc:none") != null) {
        processAnnotations = false;
    } else if (procEnvImpl == null) {
        procEnvImpl = new JavacProcessingEnvironment(context, processors);
        processAnnotations = procEnvImpl.atLeastOneProcessor();

        if (processAnnotations) {
            if (context.get(Scanner.Factory.scannerFactoryKey) == null)
                DocCommentScanner.Factory.preRegister(context);
            options.put("save-parameter-names", "save-parameter-names");
            reader.saveParameterNames = true;
            keepComments = true;
            if (taskListener != null)
                taskListener.started(new TaskEvent(TaskEvent.Kind.ANNOTATION_PROCESSING));


        } else { // free resources
            procEnvImpl.close();
        }
    }
}