DataBuffer (Spring Framework 5.2.14.RELEASE API)

All Known Subinterfaces:

PooledDataBuffer

All Known Implementing Classes:

DataBufferWrapper, DefaultDataBuffer, NettyDataBuffer
```
public interface DataBuffer
```
Basic abstraction over byte buffers.
DataBuffers has a separate read and write position, as opposed to ByteBuffer's single position. As such, the DataBuffer does not require a flip to read after writing. In general, the following invariant holds for the read and write positions, and the capacity:
0 <= readPosition <= writePosition <= capacity

The capacity of a DataBuffer is expanded on demand, similar to StringBuilder.
The main purpose of the DataBuffer abstraction is to provide a convenient wrapper around ByteBuffer which is similar to Netty's ByteBuf but can also be used on non-Netty platforms (i.e. Servlet containers).

Since:

5.0

Author:

Arjen Poutsma, Brian Clozel

See Also:

DataBufferFactory

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`ByteBuffer`	`asByteBuffer()` Expose this buffer's bytes as a `ByteBuffer`.
`ByteBuffer`	`asByteBuffer(int index, int length)` Expose a subsequence of this buffer's bytes as a `ByteBuffer`.
`InputStream`	`asInputStream()` Expose this buffer's data as an `InputStream`.
`InputStream`	`asInputStream(boolean releaseOnClose)` Expose this buffer's data as an `InputStream`.
`OutputStream`	`asOutputStream()` Expose this buffer's data as an `OutputStream`.
`int`	`capacity()` Return the number of bytes that this buffer can contain.
`DataBuffer`	`capacity(int capacity)` Set the number of bytes that this buffer can contain.
`default DataBuffer`	`ensureCapacity(int capacity)` Ensure that the current buffer has enough `writableByteCount()` to write the amount of data given as an argument.
`DataBufferFactory`	`factory()` Return the `DataBufferFactory` that created this buffer.
`byte`	`getByte(int index)` Read a single byte at the given index from this data buffer.
`int`	`indexOf(IntPredicate predicate, int fromIndex)` Return the index of the first byte in this buffer that matches the given predicate.
`int`	`lastIndexOf(IntPredicate predicate, int fromIndex)` Return the index of the last byte in this buffer that matches the given predicate.
`byte`	`read()` Read a single byte from the current reading position from this data buffer.
`DataBuffer`	`read(byte[] destination)` Read this buffer's data into the specified destination, starting at the current reading position of this buffer.
`DataBuffer`	`read(byte[] destination, int offset, int length)` Read at most `length` bytes of this buffer into the specified destination, starting at the current reading position of this buffer.
`int`	`readableByteCount()` Return the number of bytes that can be read from this data buffer.
`int`	`readPosition()` Return the position from which this buffer will read.
`DataBuffer`	`readPosition(int readPosition)` Set the position from which this buffer will read.
`default DataBuffer`	`retainedSlice(int index, int length)` Create a new `DataBuffer` whose contents is a shared, retained subsequence of this data buffer's content.
`DataBuffer`	`slice(int index, int length)` Create a new `DataBuffer` whose contents is a shared subsequence of this data buffer's content.
`default String`	`toString(Charset charset)` Return this buffer's data a String using the specified charset.
`String`	`toString(int index, int length, Charset charset)` Return a part of this buffer's data as a String using the specified charset.
`int`	`writableByteCount()` Return the number of bytes that can be written to this data buffer.
`DataBuffer`	`write(byte b)` Write a single byte into this buffer at the current writing position.
`DataBuffer`	`write(byte[] source)` Write the given source into this buffer, starting at the current writing position of this buffer.
`DataBuffer`	`write(byte[] source, int offset, int length)` Write at most `length` bytes of the given source into this buffer, starting at the current writing position of this buffer.
`DataBuffer`	`write(ByteBuffer... buffers)` Write one or more `ByteBuffer` to this buffer, starting at the current writing position.
`default DataBuffer`	`write(CharSequence charSequence, Charset charset)` Write the given `CharSequence` using the given `Charset`, starting at the current writing position.
`DataBuffer`	`write(DataBuffer... buffers)` Write one or more `DataBuffer`s to this buffer, starting at the current writing position.
`int`	`writePosition()` Return the position to which this buffer will write.
`DataBuffer`	`writePosition(int writePosition)` Set the position to which this buffer will write.

- Method Detail
  - factory
```
DataBufferFactory factory()
```
    Return the DataBufferFactory that created this buffer.
    
    Returns:
    
    the creating buffer factory
  - indexOf
```
int indexOf(IntPredicate predicate,
            int fromIndex)
```
    Return the index of the first byte in this buffer that matches the given predicate.
    
    Parameters:
    
    predicate - the predicate to match
    
    fromIndex - the index to start the search from
    
    Returns:
    
    the index of the first byte that matches predicate; or -1 if none match
  - lastIndexOf
```
int lastIndexOf(IntPredicate predicate,
                int fromIndex)
```
    Return the index of the last byte in this buffer that matches the given predicate.
    
    Parameters:
    
    predicate - the predicate to match
    
    fromIndex - the index to start the search from
    
    Returns:
    
    the index of the last byte that matches predicate; or -1 if none match
  - readableByteCount
```
int readableByteCount()
```
    Return the number of bytes that can be read from this data buffer.
    
    Returns:
    
    the readable byte count
  - writableByteCount
```
int writableByteCount()
```
    Return the number of bytes that can be written to this data buffer.
    
    Returns:
    
    the writable byte count
    
    Since:
    
    5.0.1
  - capacity
```
int capacity()
```
    Return the number of bytes that this buffer can contain.
    
    Returns:
    
    the capacity
    
    Since:
    
    5.0.1
  - capacity
```
DataBuffer capacity(int capacity)
```
    Set the number of bytes that this buffer can contain.
    If the new capacity is lower than the current capacity, the contents of this buffer will be truncated. If the new capacity is higher than the current capacity, it will be expanded.
    
    Parameters:
    
    capacity - the new capacity
    
    Returns:
    
    this buffer
  - ensureCapacity
```
default DataBuffer ensureCapacity(int capacity)
```
    Ensure that the current buffer has enough writableByteCount() to write the amount of data given as an argument. If not, the missing capacity will be added to the buffer.
    
    Parameters:
    
    capacity - the writable capacity to check for
    
    Returns:
    
    this buffer
    
    Since:
    
    5.1.4
  - readPosition
```
int readPosition()
```
    Return the position from which this buffer will read.
    
    Returns:
    
    the read position
    
    Since:
    
    5.0.1
  - readPosition
```
DataBuffer readPosition(int readPosition)
```
    Set the position from which this buffer will read.
    
    Parameters:
    
    readPosition - the new read position
    
    Returns:
    
    this buffer
    
    Throws:
    
    IndexOutOfBoundsException - if readPosition is smaller than 0 or greater than writePosition()
    
    Since:
    
    5.0.1
  - writePosition
```
int writePosition()
```
    Return the position to which this buffer will write.
    
    Returns:
    
    the write position
    
    Since:
    
    5.0.1
  - writePosition
```
DataBuffer writePosition(int writePosition)
```
    Set the position to which this buffer will write.
    
    Parameters:
    
    writePosition - the new write position
    
    Returns:
    
    this buffer
    
    Throws:
    
    IndexOutOfBoundsException - if writePosition is smaller than readPosition() or greater than capacity()
    
    Since:
    
    5.0.1
  - getByte
```
byte getByte(int index)
```
    Read a single byte at the given index from this data buffer.
    
    Parameters:
    
    index - the index at which the byte will be read
    
    Returns:
    
    the byte at the given index
    
    Throws:
    
    IndexOutOfBoundsException - when index is out of bounds
    
    Since:
    
    5.0.4
  - read
```
byte read()
```
    Read a single byte from the current reading position from this data buffer.
    
    Returns:
    
    the byte at this buffer's current reading position
  - read
```
DataBuffer read(byte[] destination)
```
    Read this buffer's data into the specified destination, starting at the current reading position of this buffer.
    
    Parameters:
    
    destination - the array into which the bytes are to be written
    
    Returns:
    
    this buffer
  - read
```
DataBuffer read(byte[] destination,
                int offset,
                int length)
```
    Read at most length bytes of this buffer into the specified destination, starting at the current reading position of this buffer.
    
    Parameters:
    
    destination - the array into which the bytes are to be written
    
    offset - the index within destination of the first byte to be written
    
    length - the maximum number of bytes to be written in destination
    
    Returns:
    
    this buffer
  - write
```
DataBuffer write(byte b)
```
    Write a single byte into this buffer at the current writing position.
    
    Parameters:
    
    b - the byte to be written
    
    Returns:
    
    this buffer
  - write
```
DataBuffer write(byte[] source)
```
    Write the given source into this buffer, starting at the current writing position of this buffer.
    
    Parameters:
    
    source - the bytes to be written into this buffer
    
    Returns:
    
    this buffer
  - write
```
DataBuffer write(byte[] source,
                 int offset,
                 int length)
```
    Write at most length bytes of the given source into this buffer, starting at the current writing position of this buffer.
    
    Parameters:
    
    source - the bytes to be written into this buffer
    
    offset - the index within source to start writing from
    
    length - the maximum number of bytes to be written from source
    
    Returns:
    
    this buffer
  - write
```
DataBuffer write(DataBuffer... buffers)
```
    Write one or more DataBuffers to this buffer, starting at the current writing position. It is the responsibility of the caller to release the given data buffers.
    
    Parameters:
    
    buffers - the byte buffers to write into this buffer
    
    Returns:
    
    this buffer
  - write
```
DataBuffer write(ByteBuffer... buffers)
```
    Write one or more ByteBuffer to this buffer, starting at the current writing position.
    
    Parameters:
    
    buffers - the byte buffers to write into this buffer
    
    Returns:
    
    this buffer
  - write
```
default DataBuffer write(CharSequence charSequence,
                         Charset charset)
```
    Write the given CharSequence using the given Charset, starting at the current writing position.
    
    Parameters:
    
    charSequence - the char sequence to write into this buffer
    
    charset - the charset to encode the char sequence with
    
    Returns:
    
    this buffer
    
    Since:
    
    5.1.4
  - slice
```
DataBuffer slice(int index,
                 int length)
```
    Create a new DataBuffer whose contents is a shared subsequence of this data buffer's content. Data between this data buffer and the returned buffer is shared; though changes in the returned buffer's position will not be reflected in the reading nor writing position of this data buffer.
    Note that this method will not call DataBufferUtils.retain(DataBuffer) on the resulting slice: the reference count will not be increased.
    
    Parameters:
    
    index - the index at which to start the slice
    
    length - the length of the slice
    
    Returns:
    
    the specified slice of this data buffer
  - retainedSlice
```
default DataBuffer retainedSlice(int index,
                                 int length)
```
    Create a new DataBuffer whose contents is a shared, retained subsequence of this data buffer's content. Data between this data buffer and the returned buffer is shared; though changes in the returned buffer's position will not be reflected in the reading nor writing position of this data buffer.
    Note that unlike slice(int, int), this method will call DataBufferUtils.retain(DataBuffer) (or equivalent) on the resulting slice.
    
    Parameters:
    
    index - the index at which to start the slice
    
    length - the length of the slice
    
    Returns:
    
    the specified, retained slice of this data buffer
    
    Since:
    
    5.2
  - asByteBuffer
```
ByteBuffer asByteBuffer()
```
    Expose this buffer's bytes as a ByteBuffer. Data between this DataBuffer and the returned ByteBuffer is shared; though changes in the returned buffer's position will not be reflected in the reading nor writing position of this data buffer.
    
    Returns:
    
    this data buffer as a byte buffer
  - asByteBuffer
```
ByteBuffer asByteBuffer(int index,
                        int length)
```
    Expose a subsequence of this buffer's bytes as a ByteBuffer. Data between this DataBuffer and the returned ByteBuffer is shared; though changes in the returned buffer's position will not be reflected in the reading nor writing position of this data buffer.
    
    Parameters:
    
    index - the index at which to start the byte buffer
    
    length - the length of the returned byte buffer
    
    Returns:
    
    this data buffer as a byte buffer
    
    Since:
    
    5.0.1
  - asInputStream
```
InputStream asInputStream()
```
    Expose this buffer's data as an InputStream. Both data and read position are shared between the returned stream and this data buffer. The underlying buffer will not be released when the input stream is closed.
    
    Returns:
    
    this data buffer as an input stream
    
    See Also:
    
    asInputStream(boolean)
  - asInputStream
```
InputStream asInputStream(boolean releaseOnClose)
```
    Expose this buffer's data as an InputStream. Both data and read position are shared between the returned stream and this data buffer.
    
    Parameters:
    
    releaseOnClose - whether the underlying buffer will be released when the input stream is closed.
    
    Returns:
    
    this data buffer as an input stream
    
    Since:
    
    5.0.4
  - asOutputStream
```
OutputStream asOutputStream()
```
    Expose this buffer's data as an OutputStream. Both data and write position are shared between the returned stream and this data buffer.
    
    Returns:
    
    this data buffer as an output stream
  - toString
```
default String toString(Charset charset)
```
    Return this buffer's data a String using the specified charset. Default implementation delegates to toString(readPosition(), readableByteCount(), charset).
    
    Parameters:
    
    charset - the character set to use
    
    Returns:
    
    a string representation of all this buffers data
    
    Since:
    
    5.2
  - toString
```
String toString(int index,
                int length,
                Charset charset)
```
    Return a part of this buffer's data as a String using the specified charset.
    
    Parameters:
    
    index - the index at which to start the string
    
    length - the number of bytes to use for the string
    
    charset - the charset to use
    
    Returns:
    
    a string representation of a part of this buffers data
    
    Since:
    
    5.2

Interface DataBuffer

Method Summary

Method Detail

factory

indexOf

lastIndexOf

readableByteCount

writableByteCount

capacity

capacity

ensureCapacity

readPosition

readPosition

writePosition

writePosition

getByte

read

read

read

write

write

write

write

write

write

slice

retainedSlice

asByteBuffer

asByteBuffer

asInputStream

asInputStream

asOutputStream

toString

toString