SimpleJavaFileObject.java

/*
 * 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
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package berlin.javax.tools;

import java.io.*;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.CharBuffer;

import berlin.javax.lang.model.element.Modifier;
import berlin.javax.lang.model.element.NestingKind;
import berlin.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.
     */
    protected SimpleJavaFileObject(URI uri, Kind kind) {
        // null checks
        uri.getClass();
        kind.getClass();
        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.
     */
    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.
     */
    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. 
     */
    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() + "]";
    }
}