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 * Copyright (c) 2005, 2012, 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

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package javax.annotation.processing;

import java.util.Map;

import java.util.Locale;

import javax.lang.model.SourceVersion;

import javax.lang.model.util.Elements;

import javax.lang.model.util.Types;

/**

 * An annotation processing tool framework will {@linkplain

 * Processor#init provide an annotation processor with an object

 * implementing this interface} so the processor can use facilities

 * provided by the framework to write new files, report error

 * messages, and find other utilities.

 *

 * <p>Third parties may wish to provide value-add wrappers around the

 * facility objects from this interface, for example a {@code Filer}

 * extension that allows multiple processors to coordinate writing out

 * a single source file.  To enable this, for processors running in a

 * context where their side effects via the API could be visible to

 * each other, the tool infrastructure must provide corresponding

 * facility objects that are {@code .equals}, {@code Filer}s that are

 * {@code .equals}, and so on.  In addition, the tool invocation must

 * be able to be configured such that from the perspective of the

 * running annotation processors, at least the chosen subset of helper

 * classes are viewed as being loaded by the same class loader.

 * (Since the facility objects manage shared state, the implementation

 * of a wrapper class must know whether or not the same base facility

 * object has been wrapped before.)

 *

 * @author Joseph D. Darcy

 * @author Scott Seligman

 * @author Peter von der Ahé

 * @since 1.6

 */

public interface ProcessingEnvironment {

    /**

     * Returns the processor-specific options passed to the annotation

     * processing tool.  Options are returned in the form of a map from

     * option name to option value.  For an option with no value, the

     * corresponding value in the map is {@code null}.

     *

     * <p>See documentation of the particular tool infrastructure

     * being used for details on how to pass in processor-specific

     * options.  For example, a command-line implementation may

     * distinguish processor-specific options by prefixing them with a

     * known string like {@code "-A"}; other tool implementations may

     * follow different conventions or provide alternative mechanisms.

     * A given implementation may also provide implementation-specific

     * ways of finding options passed to the tool in addition to the

     * processor-specific options.

     *

     * @return the processor-specific options passed to the tool

     */

    Map<String,String> getOptions();

    /**

     * Returns the messager used to report errors, warnings, and other

     * notices.

     *

     * @return the messager

     */

    Messager getMessager();

    /**

     * Returns the filer used to create new source, class, or auxiliary

     * files.

     *

     * @return the filer

     */

    Filer getFiler();

    /**

     * Returns an implementation of some utility methods for

     * operating on elements

     *

     * @return element utilities

     */

    Elements getElementUtils();

    /**

     * Returns an implementation of some utility methods for

     * operating on types.

     *

     * @return type utilities

     */

    Types getTypeUtils();

    /**

     * Returns the source version that any generated {@linkplain

     * Filer#createSourceFile source} and {@linkplain

     * Filer#createClassFile class} files should conform to.

     *

     * @return the source version to which generated source and class

     *         files should conform to

     * @see Processor#getSupportedSourceVersion

     */

    SourceVersion getSourceVersion();

    /**

     * Returns the current locale or {@code null} if no locale is in

     * effect.  The locale can be be used to provide localized

     * {@linkplain Messager messages}.

     *

     * @return the current locale or {@code null} if no locale is in

     * effect

     */

    Locale getLocale();

}