Java example source code file (TestPosition.java)

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Java - Java tags/keywords

abstractprocessor, doccommenttree, docsourcepositions, doctrees, illegalstateexception, ioexception, override, roundenvironment, sourceversion, string, supportedannotationtypes, testposition, typeelement, util, void

The TestPosition.java Java example source code

/*
 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 8008174
 * @summary proper source positions for doc comments
 * @build TestPosition
 * @compile/ref=TestPosition.out -processor TestPosition -proc:only TestPositionSource.java
 */

import com.sun.source.doctree.DocCommentTree;
import com.sun.source.doctree.DocTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.util.DocSourcePositions;
import com.sun.source.util.DocTreeScanner;
import com.sun.source.util.DocTrees;
import com.sun.source.util.TreePath;
import com.sun.source.util.TreePathScanner;
import java.io.IOException;
import java.util.Set;
import javax.annotation.processing.*;
import javax.lang.model.*;
import javax.lang.model.element.*;

@SupportedAnnotationTypes("*")
public class TestPosition extends AbstractProcessor {

    @Override
    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
        TypeElement source = processingEnv.getElementUtils().getTypeElement("TestPositionSource");

        if (source == null) throw new IllegalStateException();

        if (!roundEnv.getRootElements().contains(source)) return false;

        final DocTrees trees = DocTrees.instance(processingEnv);
        final TreePath testElement = trees.getPath(source);

        if (testElement == null) throw new IllegalStateException();

        String code;

        try {
            code = testElement.getCompilationUnit().getSourceFile().getCharContent(false).toString();
        } catch ( IOException ex) {
            throw new IllegalStateException(ex);
        }

        new TreePathScanner<Void, Void>() {
            @Override public Void visitMethod(MethodTree node, Void p) {
                final DocCommentTree docCommentTree = trees.getDocCommentTree(getCurrentPath());

                if (docCommentTree != null) {
                    System.out.println(node.getName() + ":");
                    new DocTreeScanner<Void, Void>() {
                        @Override public Void scan(DocTree node, Void p) {
                            if (node != null) {
                                DocSourcePositions sp = (DocSourcePositions) trees.getSourcePositions(); //XXX: the cast???
                                int start = (int) sp.getStartPosition(testElement.getCompilationUnit(), docCommentTree, node);
                                int end   = (int) sp.getEndPosition(testElement.getCompilationUnit(), docCommentTree, node);
                                String snippet = code.substring(start, end).replace(" \n", "!trailing-whitespace!\n");

                                if (snippet.endsWith(" ")) {
                                    snippet = snippet.substring(0, snippet.length() - 1) + "!trailing-whitespace!";
                                }
                                System.out.println(node.getKind().name() + ":" + snippet);
                            }
                            return super.scan(node, p);
                        }
                    }.scan(docCommentTree, null);
                }

                return super.visitMethod(node, p);
            }
        }.scan(testElement, null);

        return false;
    }

    @Override
    public SourceVersion getSupportedSourceVersion() {
        return SourceVersion.latest();
    }
}