Java example source code file (InheritDocTaglet.java)

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Java - Java tags/keywords

baseinlinetaglet, configuration, content, executablememberdoc, inherit_doc_inline_tag, inheritabletaglet, inheritdoctaglet, javadoc, programelementdoc, string, tagletwriter

The InheritDocTaglet.java Java example source code

/*
 * Copyright (c) 2001, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 */

package com.sun.tools.doclets.internal.toolkit.taglets;

import com.sun.javadoc.*;
import com.sun.tools.doclets.internal.toolkit.Configuration;
import com.sun.tools.doclets.internal.toolkit.Content;
import com.sun.tools.doclets.internal.toolkit.util.*;

/**
 * An inline Taglet representing the <b>inheritDoc tag. This tag should only
 * be used with a method.  It is used to inherit documentation from overriden
 * and implemented methods.
 *
 *  <p>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 *
 * @author Jamie Ho
 * @since 1.4
 */

public class InheritDocTaglet extends BaseInlineTaglet {

    /**
     * The inline tag that would appear in the documentation if
     * the writer wanted documentation to be inherited.
     */
    public static final String INHERIT_DOC_INLINE_TAG = "{@inheritDoc}";

    /**
     * Construct a new InheritDocTaglet.
     */
    public InheritDocTaglet () {
        name = "inheritDoc";
    }

    /**
     * Will return false because this inline tag may
     * not appear in Fields.
     * @return false
     */
    public boolean inField() {
        return false;
    }

    /**
     * Will return false because this inline tag may
     * not appear in Constructors.
     * @return false
     */
    public boolean inConstructor() {
        return false;
    }

    /**
     * Will return false because this inline tag may
     * not appear in Overview.
     * @return false
     */
    public boolean inOverview() {
        return false;
    }

    /**
     * Will return false because this inline tag may
     * not appear in Packages.
     * @return false
     */
    public boolean inPackage() {
        return false;
    }

    /**
     * Will return true because this inline tag may
     * appear in Type (Class).
     * @return true
     */
    public boolean inType() {
        return true;
    }

    /**
     * Given a <code>MethodDoc item, a Tag in the
     * <code>MethodDoc item and a String, replace all occurrences
     * of @inheritDoc with documentation from it's superclass or superinterface.
     *
     * @param writer the writer that is writing the output.
     * @param ped the {@link ProgramElementDoc} that we are documenting.
     * @param holderTag the tag that holds the inheritDoc tag or null for type
     * (class) docs.
     * @param isFirstSentence true if we only want to inherit the first sentence.
     */
    private Content retrieveInheritedDocumentation(TagletWriter writer,
            ProgramElementDoc ped, Tag holderTag, boolean isFirstSentence) {
        Content replacement = writer.getOutputInstance();

        Configuration configuration = writer.configuration();
        Taglet inheritableTaglet = holderTag == null ?
            null : configuration.tagletManager.getTaglet(holderTag.name());
        if (inheritableTaglet != null &&
            !(inheritableTaglet instanceof InheritableTaglet)) {
                String message = ped.name() +
                    ((ped instanceof ExecutableMemberDoc)
                        ? ((ExecutableMemberDoc)ped).flatSignature()
                        : "");
                //This tag does not support inheritence.
                configuration.message.warning(ped.position(),
                "doclet.noInheritedDoc", message);
         }
        DocFinder.Output inheritedDoc =
            DocFinder.search(new DocFinder.Input(ped,
                (InheritableTaglet) inheritableTaglet, holderTag,
                isFirstSentence, true));
        if (inheritedDoc.isValidInheritDocTag) {
            if (inheritedDoc.inlineTags.length > 0) {
                replacement = writer.commentTagsToOutput(inheritedDoc.holderTag,
                    inheritedDoc.holder, inheritedDoc.inlineTags, isFirstSentence);
            }
        } else {
            String message = ped.name() +
                    ((ped instanceof ExecutableMemberDoc)
                        ? ((ExecutableMemberDoc)ped).flatSignature()
                        : "");
            configuration.message.warning(ped.position(),
                "doclet.noInheritedDoc", message);
        }
        return replacement;
    }

    /**
     * Given the <code>Tag representation of this custom
     * tag, return its string representation, which is output
     * to the generated page.
     * @param tag the <code>Tag representation of this custom tag.
     * @param tagletWriter the taglet writer for output.
     * @return the Content representation of this <code>Tag.
     */
    public Content getTagletOutput(Tag tag, TagletWriter tagletWriter) {
        if (! (tag.holder() instanceof ProgramElementDoc)) {
            return tagletWriter.getOutputInstance();
        }
        return tag.name().equals("@inheritDoc") ?
                retrieveInheritedDocumentation(tagletWriter, (ProgramElementDoc) tag.holder(), null, tagletWriter.isFirstSentence) :
                retrieveInheritedDocumentation(tagletWriter, (ProgramElementDoc) tag.holder(), tag, tagletWriter.isFirstSentence);
    }
}