/*

 * Copyright (c) 2006, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.tools.javac.api;

import java.io.IOException;

import java.net.URI;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import java.util.Set;

import javax.tools.*;

import javax.tools.JavaFileObject.Kind;

/**

 * Wraps all calls to a given file manager.  Subclasses of this class

 * might override some of these methods and might also provide

 * additional fields and methods.

 *

 * <p>This class might be moved to {@link javax.tools} in a future

 * release.

 *

 * <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></p>

 *

 * @param <M> the type of file manager wrapped to by this object

 *

 * @author Peter von der Ahé

 * @since 1.6

 */

public class WrappingJavaFileManager<M extends JavaFileManager> extends ForwardingJavaFileManager<M> {

    /**

     * Creates a new instance of WrappingJavaFileManager.

     * @param fileManager file manager to be wrapped

     */

    protected WrappingJavaFileManager(M fileManager) {

        super(fileManager);

    }

    /**

     * This implementation returns the given file object.  Subclasses

     * may override this behavior.

     *

     * @param fileObject a file object

     */

    protected FileObject wrap(FileObject fileObject) {

        return fileObject;

    }

    /**

     * This implementation forwards to {@link #wrap(FileObject)}.

     * Subclasses may override this behavior.

     *

     * @param fileObject a file object

     * @throws ClassCastException if the file object returned from the

     * forwarded call is not a subtype of {@linkplain JavaFileObject}

     */

    protected JavaFileObject wrap(JavaFileObject fileObject) {

        return (JavaFileObject)wrap((FileObject)fileObject);

    }

    /**

     * This implementation returns the given file object.  Subclasses

     * may override this behavior.

     *

     * @param fileObject a file object

     */

    protected FileObject unwrap(FileObject fileObject) {

        return fileObject;

    }

    /**

     * This implementation forwards to {@link #unwrap(FileObject)}.

     * Subclasses may override this behavior.

     *

     * @param fileObject a file object

     * @throws ClassCastException if the file object returned from the

     * forwarded call is not a subtype of {@linkplain JavaFileObject}

     */

    protected JavaFileObject unwrap(JavaFileObject fileObject) {

        return (JavaFileObject)unwrap((FileObject)fileObject);

    }

    /**

     * This implementation maps the given list of file objects by

     * calling wrap on each.  Subclasses may override this behavior.

     *

     * @param fileObjects a list of file objects

     * @return the mapping

     */

    protected Iterable<JavaFileObject> wrap(Iterable<JavaFileObject> fileObjects) {

        List<JavaFileObject> mapped = new ArrayList<>();

        for (JavaFileObject fileObject : fileObjects)

            mapped.add(wrap(fileObject));

        return Collections.unmodifiableList(mapped);

    }

    /**

     * This implementation returns the given URI.  Subclasses may

     * override this behavior.

     *

     * @param uri a URI

     */

    protected URI unwrap(URI uri) {

        return uri;

    }

    /**

     * @throws IllegalStateException {@inheritDoc}

     */

    public Iterable<JavaFileObject> list(Location location,

                                         String packageName,

                                         Set<Kind> kinds,

                                         boolean recurse)

        throws IOException

    {

        return wrap(super.list(location, packageName, kinds, recurse));

    }

    /**

     * @throws IllegalStateException {@inheritDoc}

     */

    public String inferBinaryName(Location location, JavaFileObject file) {

        return super.inferBinaryName(location, unwrap(file));

    }

    /**

     * @throws IllegalArgumentException {@inheritDoc}

     * @throws UnsupportedOperationException {@inheritDoc}

     * @throws IllegalStateException {@inheritDoc}

     */

    public JavaFileObject getJavaFileForInput(Location location,

                                              String className,

                                              Kind kind)

        throws IOException

    {

        return wrap(super.getJavaFileForInput(location, className, kind));

    }

    /**

     * @throws IllegalArgumentException {@inheritDoc}

     * @throws UnsupportedOperationException {@inheritDoc}

     * @throws IllegalStateException {@inheritDoc}

     */

    public JavaFileObject getJavaFileForOutput(Location location,

                                               String className,

                                               Kind kind,

                                               FileObject sibling)

        throws IOException

    {

        return wrap(super.getJavaFileForOutput(location, className, kind, unwrap(sibling)));

    }

    /**

     * @throws IllegalArgumentException {@inheritDoc}

     * @throws IllegalStateException {@inheritDoc}

     */

    public FileObject getFileForInput(Location location,

                                      String packageName,

                                      String relativeName)

        throws IOException

    {

        return wrap(super.getFileForInput(location, packageName, relativeName));

    }

    /**

     * @throws IllegalArgumentException {@inheritDoc}

     * @throws IllegalStateException {@inheritDoc}

     */

    public FileObject getFileForOutput(Location location,

                                       String packageName,

                                       String relativeName,

                                       FileObject sibling)

        throws IOException

    {

        return wrap(super.getFileForOutput(location,

                                           packageName,

                                           relativeName,

                                           unwrap(sibling)));

    }

}