Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * 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 java.util.*;

 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 value tag. This tag should only be used with

  * constant fields that have a value.  It is used to access the value of constant

  * fields.  This inline tag has an optional field name parameter.  If the name is

  * specified, the constant value is retrieved from the specified field.  A link

  * is also created to the specified field.  If a name is not specified, the value

  * is retrieved for the field that the inline tag appears on.  The name is specifed

  * in the following format:  [fully qualified class name]#[constant field name].

  *

  *  <p><b>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 ValueTaglet extends BaseInlineTaglet {

     /**

      * Construct a new ValueTaglet.

      */

     public ValueTaglet() {

         name = "value";

     }

     /**

      * Will return false because this inline tag may

      * only appear in Fields.

      * @return false since this is not a method.

      */

     public boolean inMethod() {

         return true;

     }

     /**

      * Will return false because this inline tag may

      * only appear in Fields.

      * @return false since this is not a method.

      */

     public boolean inConstructor() {

         return true;

     }

     /**

      * Will return false because this inline tag may

      * only appear in Fields.

      * @return false since this is not a method.

      */

     public boolean inOverview() {

         return true;

     }

     /**

      * Will return false because this inline tag may

      * only appear in Fields.

      * @return false since this is not a method.

      */

     public boolean inPackage() {

         return true;

     }

     /**

      * Will return false because this inline tag may

      * only appear in Fields.

      * @return false since this is not a method.

      */

     public boolean inType() {

         return true;

     }

     /**

      * Given the name of the field, return the corresponding FieldDoc. Return null

      * due to invalid use of value tag if the name is null or empty string and if

      * the value tag is not used on a field.

      *

      * @param config the current configuration of the doclet.

      * @param tag the value tag.

      * @param name the name of the field to search for.  The name should be in

      * {@code <qualified class name>#<field name>} format. If the class name is omitted,

      * it is assumed that the field is in the current class.

      *

      * @return the corresponding FieldDoc. If the name is null or empty string,

      * return field that the value tag was used in. Return null if the name is null

      * or empty string and if the value tag is not used on a field.

      */

     private FieldDoc getFieldDoc(Configuration config, Tag tag, String name) {

         if (name == null || name.length() == 0) {

             //Base case: no label.

             if (tag.holder() instanceof FieldDoc) {

                 return (FieldDoc) tag.holder();

             } else {

                 // If the value tag does not specify a parameter which is a valid field and

                 // it is not used within the comments of a valid field, return null.

                  return null;

             }

         }

         StringTokenizer st = new StringTokenizer(name, "#");

         String memberName = null;

         ClassDoc cd = null;

         if (st.countTokens() == 1) {

             //Case 2:  @value in same class.

             Doc holder = tag.holder();

             if (holder instanceof MemberDoc) {

                 cd = ((MemberDoc) holder).containingClass();

             } else if (holder instanceof ClassDoc) {

                 cd = (ClassDoc) holder;

             }

             memberName = st.nextToken();

         } else {

             //Case 3: @value in different class.

             cd = config.root.classNamed(st.nextToken());

             memberName = st.nextToken();

         }

         if (cd == null) {

             return null;

         }

         FieldDoc[] fields = cd.fields();

         for (int i = 0; i < fields.length; i++) {

             if (fields[i].name().equals(memberName)) {

                 return fields[i];

             }

         }

         return null;

     }

     /**

      * {@inheritDoc}

      */

     public Content getTagletOutput(Tag tag, TagletWriter writer) {

         FieldDoc field = getFieldDoc(

             writer.configuration(), tag, tag.text());

         if (field == null) {

             if (tag.text().isEmpty()) {

                 //Invalid use of @value

                 writer.getMsgRetriever().warning(tag.holder().position(),

                         "doclet.value_tag_invalid_use");

             } else {

                 //Reference is unknown.

                 writer.getMsgRetriever().warning(tag.holder().position(),

                         "doclet.value_tag_invalid_reference", tag.text());

             }

         } else if (field.constantValue() != null) {

             return writer.valueTagOutput(field,

                 field.constantValueExpression(),

                 ! field.equals(tag.holder()));

         } else {

             //Referenced field is not a constant.

             writer.getMsgRetriever().warning(tag.holder().position(),

                 "doclet.value_tag_invalid_constant", field.name());

         }

         return writer.getOutputInstance();

     }

 }