android-platform-libcore/luni/src/main/java/java/nio/ReadOnlyDirectByteBuffer.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.
 */

package java.nio;

import org.apache.harmony.luni.platform.PlatformAddress;

/**
 * DirectByteBuffer, ReadWriteDirectByteBuffer and ReadOnlyDirectByteBuffer
 * compose the implementation of platform memory based byte buffers.
 * <p>
 * ReadOnlyDirectByteBuffer extends DirectByteBuffer with all the write methods
 * throwing read only exception.
 * </p>
 * <p>
 * This class is marked final for runtime performance.
 * </p>
 *
 */
final class ReadOnlyDirectByteBuffer extends DirectByteBuffer {

    static ReadOnlyDirectByteBuffer copy(DirectByteBuffer other, int markOfOther) {
        ReadOnlyDirectByteBuffer buf = new ReadOnlyDirectByteBuffer(
                other.safeAddress, other.capacity(), other.offset);
        buf.limit = other.limit();
        buf.position = other.position();
        buf.mark = markOfOther;
        buf.order(other.order());
        return buf;
    }

    protected ReadOnlyDirectByteBuffer(SafeAddress address, int capacity, int offset) {
        super(address, capacity, offset);
    }

    protected ReadOnlyDirectByteBuffer(PlatformAddress address, int capacity, int offset) {
        super(new SafeAddress(address), capacity, offset);
    }

    @Override
    public ByteBuffer asReadOnlyBuffer() {
        return copy(this, mark);
    }

    @Override
    public ByteBuffer compact() {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer duplicate() {
        return copy(this, mark);
    }

    @Override
    public boolean isReadOnly() {
        return true;
    }

    @Override
    public ByteBuffer put(byte value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer put(int index, byte value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer put(byte[] src, int off, int len) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putDouble(double value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putDouble(int index, double value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putFloat(float value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putFloat(int index, float value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putInt(int value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putInt(int index, int value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putLong(int index, long value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putLong(long value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putShort(int index, short value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer putShort(short value) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer put(ByteBuffer buf) {
        throw new ReadOnlyBufferException();
    }

    @Override
    public ByteBuffer slice() {
        ReadOnlyDirectByteBuffer buf = new ReadOnlyDirectByteBuffer(
                safeAddress, remaining(), offset + position);
        buf.order = order;
        return buf;
    }

}