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 * published by the Free Software Foundation.  Oracle designates this

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 * 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

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 *

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package jdk.javadoc.doclet;

import java.util.List;

import java.util.Locale;

import java.util.Set;

import javax.lang.model.SourceVersion;

/**

 * The user doclet must implement this interface, as described in the

 * Each implementation of a Doclet must provide a public no-argument constructor

 * to be used by tools to instantiate the doclet. The tool infrastructure will

 * interact with classes implementing this interface as follows:

 * <ol>

 * <li> The tool will create an instance of a doclet using the no-arg constructor

 *  of the doclet class.

 * <li> Next, the tool calls the {@link #init init} method with an appropriate locale

 *  and reporter.

 * <li> Afterwards, the tool calls {@link #getSupportedOptions getSupportedOptions},

 * and {@link #getSupportedSourceVersion getSupportedSourceVersion}.

 * These methods are only called once.

 * <li> As appropriate, the tool calls the {@link #run run} method on the doclet

 * object, giving it a DocletEnvironment object, from which the doclet can determine

 * the elements to be included in the documentation.

 * </ol>

 * <p>

 * If a doclet object is created and used without the above protocol being followed,

 * then the doclet's behavior is not defined by this interface specification.

 * <p> To start the doclet, pass {@code -doclet} followed by the fully-qualified

 * name of the entry point class (i.e. the implementation of this interface) on

 * the javadoc tool command line.

 *

 * @since 9

 */

public interface Doclet {

    /**

     * Initializes this doclet with the given locale and error reporter.

     * This locale will be used by the reporter and the doclet components.

     *

     * @param locale the locale to be used

     * @param reporter the reporter to be used

     */

    void init(Locale locale, Reporter reporter);

    /**

     * Returns a name identifying the doclet. A name is a simple identifier

     * without white spaces, as defined in <cite>The Java&trade; Language Specification</cite>,

     * section 6.2 "Names and Identifiers".

     *

     * @return name of the Doclet

     */

    String getName();

    /**

     * Returns all the supported options.

     *

     * @return a set containing all the supported options, an empty set if none

     */

    Set<? extends Option> getSupportedOptions();

    /**

     * Returns the version of the Java Programming Language supported

     * by this doclet.

     *

     * @return  the language version supported by this doclet, usually

     * the latest version

     */

    SourceVersion getSupportedSourceVersion();

    /**

     * The entry point of the doclet. Further processing will commence as

     * instructed by this method.

     *

     * @param environment from which essential information can be extracted

     * @return true on success

     */

    boolean run(DocletEnvironment environment);

    /**

     * An encapsulation of option name, aliases, parameters and descriptions

     * as used by the Doclet.

     */

    interface Option {

        /**

         * Returns the number of arguments, this option will consume.

         * @return number of consumed arguments

         */

        int getArgumentCount();

        /**

         * Returns the description of the option. For instance, the option "group", would

         * return the synopsis of the option such as, "groups the documents".

         * @return description if set, otherwise an empty String

         */

        String getDescription();

        /**

         * Returns the option kind.

         * @return the kind of this option

         */

        Option.Kind getKind();

        /**

         * Returns the list of names that may be used to identify the option. For instance, the

         * list could be {@code ["-classpath", "--class-path"]} for the

         * option "-classpath", with an alias "--class-path".

         * @return the names of the option

         */

        List<String> getNames();

        /**

         * Returns the parameters of the option. For instance "name <p1>:<p2>.."

         * @return parameters if set, otherwise an empty String

         */

        String getParameters();

        /**

         * Processes the option and arguments as needed. This method will

         * be invoked if the given option name matches the option.

         * @param option the option

         * @param arguments a list encapsulating the arguments

         * @return true if operation succeeded, false otherwise

         */

        boolean process(String option, List<String> arguments);

        /**

         * The kind of an option.

         */

        public static enum Kind {

            /** an extended option, such as those prefixed with -X */

            EXTENDED,

            /** a standard option */

            STANDARD,

            /** an implementation reserved option */

            OTHER;

        }

    }

}