Bytearrayinputstream of Java Byte stream

The role of Bytearrayinputstream:

Contains an internal buffer that contains bytes that can be read from the stream. The internal counter tracks read the next byte provided by the method. Close one ByteArrayInputStream without any effect. The methods in the stream can be called after the stream is closed, not generated IOException . This means that, for example, a file stream handles a file in the external memory of an object, and its processing object is an in-memory buffer. It is read from one memory to another in memory mode.

Fields

Modifier and Type	Field	Description
protected byte[]	buf	An array of bytes provided by the creator of the data stream.
protected int	count	Index one is greater than the last valid character in the input stream buffer.
protected int	mark	The position of the current marker in the stream.
protected int	pos	The index of the next character read from the input stream buffer.

construction method  

constructor	Description
Bytearrayinputstream? (byte[] buf)	Bytearrayinputstream that uses buf as its buffer array.
By Tearrayinputstream? (Byte[] buf, Int offset, int length)	Create bytearrayinputstream use buf as its buffer array.

Modifier and Type	Method	Description
int	available?()	Returns the number of bytes remaining that can be read (or skipped) from this input stream.
void	close?()	Close one ByteArrayInputStream without any effect.
void	mark?(int readAheadLimit)	Sets the position of the current marker in the stream.
boolean	markSupported?()	Test this InputStream support tag/reset.
int	read?()	Reads the next data byte from the input stream.
int	read?(byte[] b, int off, int len)	Reads up len to a byte array of data from the input stream.
void	reset?()	Resets the buffer to the marker position.
long	skip?(long n)	Skips the byte input of this input stream n .

Note:

Public bytearrayinputstream? (byte[] buf,  int offset, int length)

Create ByteArrayInputStreamUse bufAs its buffer array. posIs offsetAnd the initial value, countis the smallest offset+lengthAnd buf.length。 The buffer array is not copied. The marker for the buffer is set to the specified offset.

Parameters

buf -Input buffer.

offset -The offset in the buffer to read the first byte.

length -The maximum number of bytes read from the buffer.

Bytearrayinputstream of Java Byte stream