/*

 * Copyright (c) 2005, 2006, 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 javax.tools;

import java.io.*;

import java.net.URI;

import java.nio.CharBuffer;

import java.util.Objects;

import javax.lang.model.element.Modifier;

import javax.lang.model.element.NestingKind;

import javax.tools.JavaFileObject.Kind;

/**

 * Provides simple implementations for most methods in JavaFileObject.

 * This class is designed to be subclassed and used as a basis for

 * JavaFileObject implementations.  Subclasses can override the

 * implementation and specification of any method of this class as

 * long as the general contract of JavaFileObject is obeyed.

 *

 * @author Peter von der Ahé

 * @since 1.6

 */

public class SimpleJavaFileObject implements JavaFileObject {

    /**

     * A URI for this file object.

     */

    protected final URI uri;

    /**

     * The kind of this file object.

     */

    protected final Kind kind;

    /**

     * Construct a SimpleJavaFileObject of the given kind and with the

     * given URI.

     *

     * @param uri  the URI for this file object

     * @param kind the kind of this file object

     */

    protected SimpleJavaFileObject(URI uri, Kind kind) {

        Objects.requireNonNull(uri);

        Objects.requireNonNull(kind);

        if (uri.getPath() == null)

            throw new IllegalArgumentException("URI must have a path: " + uri);

        this.uri = uri;

        this.kind = kind;

    }

    public URI toUri() {

        return uri;

    }

    public String getName() {

        return toUri().getPath();

    }

    /**

     * This implementation always throws {@linkplain

     * UnsupportedOperationException}.  Subclasses can change this

     * behavior as long as the contract of {@link FileObject} is

     * obeyed.

     */

    public InputStream openInputStream() throws IOException {

        throw new UnsupportedOperationException();

    }

    /**

     * This implementation always throws {@linkplain

     * UnsupportedOperationException}.  Subclasses can change this

     * behavior as long as the contract of {@link FileObject} is

     * obeyed.

     */

    public OutputStream openOutputStream() throws IOException {

        throw new UnsupportedOperationException();

    }

    /**

     * Wraps the result of {@linkplain #getCharContent} in a Reader.

     * Subclasses can change this behavior as long as the contract of

     * {@link FileObject} is obeyed.

     *

     * @param  ignoreEncodingErrors {@inheritDoc}

     * @return a Reader wrapping the result of getCharContent

     * @throws IllegalStateException {@inheritDoc}

     * @throws UnsupportedOperationException {@inheritDoc}

     * @throws IOException {@inheritDoc}

     */

    public Reader openReader(boolean ignoreEncodingErrors) throws IOException {

        CharSequence charContent = getCharContent(ignoreEncodingErrors);

        if (charContent == null)

            throw new UnsupportedOperationException();

        if (charContent instanceof CharBuffer) {

            CharBuffer buffer = (CharBuffer)charContent;

            if (buffer.hasArray())

                return new CharArrayReader(buffer.array());

        }

        return new StringReader(charContent.toString());

    }

    /**

     * This implementation always throws {@linkplain

     * UnsupportedOperationException}.  Subclasses can change this

     * behavior as long as the contract of {@link FileObject} is

     * obeyed.

     */

    public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {

        throw new UnsupportedOperationException();

    }

    /**

     * Wraps the result of openOutputStream in a Writer.  Subclasses

     * can change this behavior as long as the contract of {@link

     * FileObject} is obeyed.

     *

     * @return a Writer wrapping the result of openOutputStream

     * @throws IllegalStateException {@inheritDoc}

     * @throws UnsupportedOperationException {@inheritDoc}

     * @throws IOException {@inheritDoc}

     */

    public Writer openWriter() throws IOException {

        return new OutputStreamWriter(openOutputStream());

    }

    /**

     * This implementation returns {@code 0L}.  Subclasses can change

     * this behavior as long as the contract of {@link FileObject} is

     * obeyed.

     *

     * @return {@code 0L}

     */

    public long getLastModified() {

        return 0L;

    }

    /**

     * This implementation does nothing.  Subclasses can change this

     * behavior as long as the contract of {@link FileObject} is

     * obeyed.

     *

     * @return {@code false}

     */

    public boolean delete() {

        return false;

    }

    /**

     * @return {@code this.kind}

     */

    public Kind getKind() {

        return kind;

    }

    /**

     * This implementation compares the path of its URI to the given

     * simple name.  This method returns true if the given kind is

     * equal to the kind of this object, and if the path is equal to

     * {@code simpleName + kind.extension} or if it ends with {@code

     * "/" + simpleName + kind.extension}.

     *

     * <p>This method calls {@link #getKind} and {@link #toUri} and

     * does not access the fields {@link #uri} and {@link #kind}

     * directly.

     *

     * <p>Subclasses can change this behavior as long as the contract

     * of {@link JavaFileObject} is obeyed.

     */

    public boolean isNameCompatible(String simpleName, Kind kind) {

        String baseName = simpleName + kind.extension;

        return kind.equals(getKind())

            && (baseName.equals(toUri().getPath())

                || toUri().getPath().endsWith("/" + baseName));

    }

    /**

     * This implementation returns {@code null}.  Subclasses can

     * change this behavior as long as the contract of

     * {@link JavaFileObject} is obeyed.

     */

    public NestingKind getNestingKind() { return null; }

    /**

     * This implementation returns {@code null}.  Subclasses can

     * change this behavior as long as the contract of

     * {@link JavaFileObject} is obeyed.

     */

    public Modifier getAccessLevel()  { return null; }

    @Override

    public String toString() {

        return getClass().getName() + "[" + toUri() + "]";

    }

}