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WriteOnlyFileChannel.javaAPI DocAndroid 1.5 API3745Wed May 06 22:41:04 BST 2009org.apache.harmony.nio.internal

WriteOnlyFileChannel.java

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

/*
 * Android Notice 
 * In this class the address length was changed from long to int.
 * This is due to performance optimizations for the device.
 */

package org.apache.harmony.nio.internal;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.FileLock;
import java.nio.channels.NonReadableChannelException;
import java.nio.channels.WritableByteChannel;

public final class WriteOnlyFileChannel extends FileChannelImpl {

    private boolean append = false;

    public WriteOnlyFileChannel(Object stream, int handle) {
        super(stream, handle);
    }

    public WriteOnlyFileChannel(Object stream, int handle, boolean isAppend) {
        super(stream, handle);
        append = isAppend;
    }
    
    /*
     * (non-Javadoc)
     * @see org.apache.harmony.nio.internal.FileChannelImpl#position()
     */
    public long position() throws IOException {
        return append ? size() : super.position();
    }

    public long transferTo(long position, long count, WritableByteChannel target)
            throws IOException {
        openCheck();
        if (!target.isOpen()) {
            throw new ClosedChannelException();
        }
        throw new NonReadableChannelException();
    }

    public long read(ByteBuffer[] buffers, int offset, int length)
            throws IOException {        
        if (offset < 0 || length < 0 || offset + length > buffers.length) {
            throw new IndexOutOfBoundsException();
        }
        openCheck();
        throw new NonReadableChannelException();
    }

    public int read(ByteBuffer buffer) throws IOException {
        openCheck();
        throw new NonReadableChannelException();
    }

    public int read(ByteBuffer buffer, long position) throws IOException {        
        if (null == buffer) {
            throw new NullPointerException();
        }
        if (position < 0){
            throw new IllegalArgumentException();
        }
        throw new NonReadableChannelException();
    }

    public MappedByteBuffer map(MapMode mode, long position, long size)
            throws IOException {
        openCheck();
        if (mode == null) {
            throw new NullPointerException();
        }
        if (position < 0 || size < 0 || size > Integer.MAX_VALUE) {
            throw new IllegalArgumentException();
        }
        throw new NonReadableChannelException();
    }

    public int write(ByteBuffer buffer) throws IOException {
        if (append) {
            position(size());
        }
        return super.write(buffer);
    }

    protected final FileLock basicLock(long position, long size,
            boolean shared, boolean wait) throws IOException {
        if (shared) {
            throw new NonReadableChannelException();
        }
        return super.basicLock(position, size, shared, wait);
    }

}