Plugin.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package com.sun.source.util;

import java.util.ServiceLoader;
import javax.tools.StandardLocation;

/**
 * The interface for a javac plug-in.
 *
 * <p>The javac plug-in mechanism allows a user to specify one or more plug-ins
 * on the javac command line, to be started soon after the compilation
 * has begun. Plug-ins are identified by a user-friendly name. Each plug-in that
 * is started will be passed an array of strings, which may be used to
 * provide the plug-in with values for any desired options or other arguments.
 *
 * <p>Plug-ins are located via a {@link ServiceLoader},
 * using the same class path as annotation processors (i.e.
 * {@link StandardLocation#ANNOTATION_PROCESSOR_PATH ANNOTATION_PROCESSOR_PATH} or
 * {@code -processorpath}).
 *
 * <p>It is expected that a typical plug-in will simply register a
 * {@link TaskListener} to be informed of events during the execution
 * of the compilation, and that the rest of the work will be done
 * by the task listener.
 *
 * @since 1.8
 */
public interface Plugin {
    /**
     * Returns the user-friendly name of this plug-in.
     * @return the user-friendly name of the plug-in
     */
    String getName();

    /**
     * Initializes the plug-in for a given compilation task.
     * @param task The compilation task that has just been started
     * @param args Arguments, if any, for the plug-in
     */
    void init(JavacTask task, String... args);

    /**
     * Returns whether or not this plugin should be automatically started,
     * even if not explicitly specified in the command-line options.
     *
     * <p>This method will be called by javac for all plugins located by the
     * service loader. If the method returns {@code true}, the plugin will be
     * {@link #init(JavacTask,String[]) initialized} with an empty array of
     * string arguments if it is not otherwise initialized due to an explicit
     * command-line option.
     *
     * @return whether or not this plugin should be automatically started
     */
    default boolean autoStart() {
        return false;
    }
}