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;

/**
 * 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.block, other.capacity(), other.offset);
        buf.limit = other.limit;
        buf.position = other.position();
        buf.mark = markOfOther;
        return buf;
    }

    protected ReadOnlyDirectByteBuffer(MemoryBlock block, int capacity, int offset) {
        super(block, 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 srcOffset, int byteCount) {
        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() {
        return new ReadOnlyDirectByteBuffer(block, remaining(), offset + position);
    }

    @Override protected byte[] protectedArray() {
        throw new ReadOnlyBufferException();
    }

    @Override protected int protectedArrayOffset() {
        throw new ReadOnlyBufferException();
    }

    @Override protected boolean protectedHasArray() {
        return false;
    }
}