How to use

DefaultDataBuffer

in

org.springframework.core.io.buffer

  @Override
  public void write(byte[] bytes, int off, int len) throws IOException {
    DefaultDataBuffer.this.write(bytes, off, len);
  }
}

static DefaultDataBuffer fromFilledByteBuffer(DefaultDataBufferFactory dataBufferFactory, ByteBuffer byteBuffer) {
  DefaultDataBuffer dataBuffer = new DefaultDataBuffer(dataBufferFactory, byteBuffer);
  dataBuffer.writePosition(byteBuffer.remaining());
  return dataBuffer;
}

  throw new IllegalArgumentException(String.format("'newCapacity' %d must be higher than 0", newCapacity));
int readPosition = readPosition();
int writePosition = writePosition();
int oldCapacity = capacity();
  ByteBuffer newBuffer = allocate(newCapacity, oldBuffer.isDirect());
  ((Buffer) oldBuffer).position(0).limit(oldBuffer.capacity());
  ((Buffer) newBuffer).position(0).limit(oldBuffer.capacity());
  newBuffer.put(oldBuffer);
  newBuffer.clear();
  setNativeBuffer(newBuffer);
  ByteBuffer newBuffer = allocate(newCapacity, oldBuffer.isDirect());
  if (readPosition < newCapacity) {
    if (writePosition > newCapacity) {
      writePosition = newCapacity;
      writePosition(writePosition);
    readPosition(newCapacity);
    writePosition(newCapacity);
  setNativeBuffer(newBuffer);

@Override
public DataBuffer ensureCapacity(int length) {
  if (length > writableByteCount()) {
    int newCapacity = calculateCapacity(this.writePosition + length);
    capacity(newCapacity);
  }
  return this;
}

@Override
public ByteBuffer asByteBuffer() {
  return asByteBuffer(this.readPosition, readableByteCount());
}

@Override
public DefaultDataBuffer writePosition(int writePosition) {
  assertIndex(writePosition >= this.readPosition, "'writePosition' %d must be >= %d",
      writePosition, this.readPosition);
  assertIndex(writePosition <= this.capacity, "'writePosition' %d must be <= %d",
      writePosition, this.capacity);
  this.writePosition = writePosition;
  return this;
}

@Override
public DefaultDataBuffer write(byte b) {
  ensureCapacity(1);
  int pos = this.writePosition;
  this.byteBuffer.put(pos, b);
  this.writePosition = pos + 1;
  return this;
}

@Override
public ByteBuffer asByteBuffer(int index, int length) {
  checkIndex(index, length);
  ByteBuffer duplicate = this.byteBuffer.duplicate();
  // Explicit access via Buffer base type for compatibility
  // with covariant return type on JDK 9's ByteBuffer...
  Buffer buffer = duplicate;
  buffer.position(index);
  buffer.limit(index + length);
  return duplicate.slice();
}

@Override
public DefaultDataBuffer allocateBuffer(int initialCapacity) {
  ByteBuffer byteBuffer = (this.preferDirect ?
      ByteBuffer.allocateDirect(initialCapacity) :
      ByteBuffer.allocate(initialCapacity));
  return DefaultDataBuffer.fromEmptyByteBuffer(this, byteBuffer);
}

static DefaultDataBuffer fromEmptyByteBuffer(DefaultDataBufferFactory dataBufferFactory, ByteBuffer byteBuffer) {
  return new DefaultDataBuffer(dataBufferFactory, byteBuffer);
}

@Override
public DataBuffer ensureCapacity(int length) {
  if (length > writableByteCount()) {
    int newCapacity = calculateCapacity(this.writePosition + length);
    capacity(newCapacity);
  }
  return this;
}

@Override
public DefaultDataBuffer readPosition(int readPosition) {
  assertIndex(readPosition >= 0, "'readPosition' %d must be >= 0", readPosition);
  assertIndex(readPosition <= this.writePosition, "'readPosition' %d must be <= %d",
      readPosition, this.writePosition);
  this.readPosition = readPosition;
  return this;
}

@Override
public ByteBuffer asByteBuffer() {
  return asByteBuffer(this.readPosition, readableByteCount());
}

@Override
public DefaultDataBuffer write(ByteBuffer... buffers) {
  if (!ObjectUtils.isEmpty(buffers)) {
    int capacity = Arrays.stream(buffers).mapToInt(ByteBuffer::remaining).sum();
    ensureCapacity(capacity);
    Arrays.stream(buffers).forEach(this::write);
  }
  return this;
}

@Override
public DefaultDataBuffer slice(int index, int length) {
  checkIndex(index, length);
  int oldPosition = this.byteBuffer.position();
  // Explicit access via Buffer base type for compatibility
  // with covariant return type on JDK 9's ByteBuffer...
  Buffer buffer = this.byteBuffer;
  try {
    buffer.position(index);
    ByteBuffer slice = this.byteBuffer.slice();
    // Explicit cast for compatibility with covariant return type on JDK 9's ByteBuffer
    ((Buffer) slice).limit(length);
    return new SlicedDefaultDataBuffer(slice, this.dataBufferFactory, length);
  }
  finally {
    buffer.position(oldPosition);
  }
}

@Override
public DefaultDataBuffer allocateBuffer(int initialCapacity) {
  ByteBuffer byteBuffer = (this.preferDirect ?
      ByteBuffer.allocateDirect(initialCapacity) :
      ByteBuffer.allocate(initialCapacity));
  return DefaultDataBuffer.fromEmptyByteBuffer(this, byteBuffer);
}

static DefaultDataBuffer fromEmptyByteBuffer(DefaultDataBufferFactory dataBufferFactory, ByteBuffer byteBuffer) {
  return new DefaultDataBuffer(dataBufferFactory, byteBuffer);
}

  throw new IllegalArgumentException(String.format("'newCapacity' %d must be higher than 0", newCapacity));
int readPosition = readPosition();
int writePosition = writePosition();
int oldCapacity = capacity();
  ByteBuffer newBuffer = allocate(newCapacity, oldBuffer.isDirect());
  ((Buffer) oldBuffer).position(0).limit(oldBuffer.capacity());
  ((Buffer) newBuffer).position(0).limit(oldBuffer.capacity());
  newBuffer.put(oldBuffer);
  newBuffer.clear();
  setNativeBuffer(newBuffer);
  ByteBuffer newBuffer = allocate(newCapacity, oldBuffer.isDirect());
  if (readPosition < newCapacity) {
    if (writePosition > newCapacity) {
      writePosition = newCapacity;
      writePosition(writePosition);
    readPosition(newCapacity);
    writePosition(newCapacity);
  setNativeBuffer(newBuffer);

@Override
public void write(int b) throws IOException {
  DefaultDataBuffer.this.write((byte) b);
}

private void ensureCapacity(int length) {
  if (length <= writableByteCount()) {
    return;
  }
  int newCapacity = calculateCapacity(this.writePosition + length);
  capacity(newCapacity);
}