| /* |
| * 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 org.apache.qpid.proton.engine.impl; |
| |
| import java.nio.ByteBuffer; |
| |
| import org.apache.qpid.proton.codec.ReadableBuffer; |
| import org.apache.qpid.proton.codec.WritableBuffer; |
| |
| public class FrameWriterBuffer implements WritableBuffer { |
| |
| public final static int DEFAULT_CAPACITY = 1024; |
| |
| byte array[]; |
| int position; |
| |
| /** |
| * Creates a new WritableBuffer with default capacity. |
| */ |
| public FrameWriterBuffer() { |
| this(DEFAULT_CAPACITY); |
| } |
| |
| /** |
| * Create a new WritableBuffer with the given capacity. |
| * |
| * @param capacity |
| * the inital capacity to allocate for this buffer. |
| */ |
| public FrameWriterBuffer(int capacity) { |
| this.array = new byte[capacity]; |
| } |
| |
| public byte[] array() { |
| return array; |
| } |
| |
| public int arrayOffset() { |
| return 0; |
| } |
| |
| @Override |
| public void put(byte b) { |
| ensureRemaining(Byte.BYTES); |
| array[position++] = b; |
| } |
| |
| @Override |
| public void putShort(short value) { |
| ensureRemaining(Short.BYTES); |
| array[position++] = (byte)(value >>> 8); |
| array[position++] = (byte)(value >>> 0); |
| } |
| |
| @Override |
| public void putInt(int value) { |
| ensureRemaining(Integer.BYTES); |
| array[position++] = (byte)(value >>> 24); |
| array[position++] = (byte)(value >>> 16); |
| array[position++] = (byte)(value >>> 8); |
| array[position++] = (byte)(value >>> 0); |
| } |
| |
| @Override |
| public void putLong(long value) { |
| ensureRemaining(Long.BYTES); |
| array[position++] = (byte)(value >>> 56); |
| array[position++] = (byte)(value >>> 48); |
| array[position++] = (byte)(value >>> 40); |
| array[position++] = (byte)(value >>> 32); |
| array[position++] = (byte)(value >>> 24); |
| array[position++] = (byte)(value >>> 16); |
| array[position++] = (byte)(value >>> 8); |
| array[position++] = (byte)(value >>> 0); |
| } |
| |
| @Override |
| public void putFloat(float value) { |
| putInt(Float.floatToRawIntBits(value)); |
| } |
| |
| @Override |
| public void putDouble(double value) { |
| putLong(Double.doubleToRawLongBits(value)); |
| } |
| |
| @Override |
| public void put(byte[] src, int offset, int length) { |
| if (length == 0) { |
| return; |
| } |
| |
| ensureRemaining(length); |
| System.arraycopy(src, offset, array, position, length); |
| position += length; |
| } |
| |
| @Override |
| public void put(ByteBuffer payload) { |
| final int toCopy = payload.remaining(); |
| ensureRemaining(toCopy); |
| |
| if (payload.hasArray()) { |
| System.arraycopy(payload.array(), payload.arrayOffset() + payload.position(), array, position, toCopy); |
| payload.position(payload.position() + toCopy); |
| } else { |
| payload.get(array, position, toCopy); |
| } |
| |
| position += toCopy; |
| } |
| |
| @Override |
| public void put(ReadableBuffer payload) { |
| final int toCopy = payload.remaining(); |
| ensureRemaining(toCopy); |
| |
| if (payload.hasArray()) { |
| System.arraycopy(payload.array(), payload.arrayOffset() + payload.position(), array, position, toCopy); |
| payload.position(payload.position() + toCopy); |
| } else { |
| payload.get(array, position, toCopy); |
| } |
| |
| position += toCopy; |
| } |
| |
| @Override |
| public boolean hasRemaining() { |
| return position < Integer.MAX_VALUE; |
| } |
| |
| @Override |
| public int remaining() { |
| return Integer.MAX_VALUE - position; |
| } |
| |
| /** |
| * Ensures the the buffer has at least the requiredRemaining space specified. |
| * <p> |
| * The internal buffer will be doubled if the requested capacity is less than that |
| * amount or the buffer will be expanded to the full new requiredRemaining value. |
| * |
| * @param requiredRemaining |
| * the minimum remaining bytes needed to meet the next write operation. |
| */ |
| @Override |
| public void ensureRemaining(int requiredRemaining) { |
| if (requiredRemaining > array.length - position) { |
| byte newBuffer[] = new byte[Math.max(array.length << 1, requiredRemaining + position)]; |
| System.arraycopy(array, 0, newBuffer, 0, array.length); |
| array = newBuffer; |
| } |
| } |
| |
| @Override |
| public int position() { |
| return position; |
| } |
| |
| @Override |
| public void position(int position) { |
| if (position < 0) { |
| throw new IllegalArgumentException("Requested new buffer position cannot be negative"); |
| } |
| |
| if (position > array.length) { |
| ensureRemaining(position - array.length); |
| } |
| |
| this.position = position; |
| } |
| |
| @Override |
| public int limit() { |
| return Integer.MAX_VALUE; |
| } |
| |
| /** |
| * Copy bytes from this buffer into the target buffer and compacts this buffer. |
| * <p> |
| * Copy either all bytes written into this buffer (start to current position) or |
| * as many as will fit if the target capacity is less that the bytes written. Bytes |
| * not read from this buffer are moved to the front of the buffer and the position is |
| * reset to the end of the copied region. |
| * |
| * @param target |
| * The array to move bytes to from those written into this buffer. |
| * |
| * @return the number of bytes transfered to the target buffer. |
| */ |
| public int transferTo(ByteBuffer target) { |
| int size = Math.min(position, target.remaining()); |
| |
| if (size == 0) { |
| return 0; |
| } |
| |
| if (target.hasArray()) { |
| System.arraycopy(array, 0, target.array(), target.arrayOffset() + target.position(), size); |
| target.position(target.position() + size); |
| } else { |
| target.put(array, 0, size); |
| } |
| |
| // Compact any remaining data to the front of the array so that new writes can reuse |
| // space previously allocated and not extend the array if possible. |
| if (size != position) { |
| int remainder = position - size; |
| System.arraycopy(array, size, array, 0, remainder); |
| position = remainder; // ensure we are at end of unread chunk |
| } else { |
| position = 0; // reset to empty state. |
| } |
| |
| return size; |
| } |
| } |