org.apache.cassandra.io.util

## Class FastByteArrayInputStream

- java.lang.Object
- - java.io.InputStream
  - - org.apache.cassandra.io.util.FastByteArrayInputStream

All Implemented Interfaces:
  java.io.Closeable, java.lang.AutoCloseable

    public class FastByteArrayInputStream
    extends java.io.InputStream

A specialized `InputStream` for reading the contents of a byte array.

See Also:
  `ByteArrayInputStream`

### Field Summary

Fields
`protected byte[]` `buf` The `byte` array containing the bytes to stream over.
`protected int` `count` The total number of bytes initially available in the byte array `buf`.
`protected int` `mark` The current mark position.
`protected int` `pos` The current position within the byte array.

### Constructor Summary

Constructors
Constructor and Description
`FastByteArrayInputStream(byte[] buf)` Constructs a new `ByteArrayInputStream` on the byte array `buf`.
`FastByteArrayInputStream(byte[] buf, int offset, int length)` Constructs a new `ByteArrayInputStream` on the byte array `buf` with the initial position set to `offset` and the number of bytes available set to `offset` + `length`.

### Method Summary

All Methods Instance Methods Concrete Methods
`int` `available()` Returns the number of bytes that are available before this stream will block.
`void` `close()` Closes this stream and frees resources associated with this stream.
`void` `mark(int readlimit)` Sets a mark position in this ByteArrayInputStream.
`boolean` `markSupported()` Indicates whether this stream supports the `mark()` and `reset()` methods.
`int` `read()` Reads a single byte from the source byte array and returns it as an integer in the range from 0 to 255.
`int` `read(byte[] b, int offset, int length)` Reads at most `len` bytes from this stream and stores them in byte array `b` starting at `offset`.
`void` `reset()` Resets this stream to the last marked location.
`long` `skip(long n)` Skips `count` number of bytes in this InputStream.

### Methods inherited from class java.io.InputStream

`read`

### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

### Field Detail

#### buf

    protected byte[] buf

The `byte` array containing the bytes to stream over.

#### pos

    protected int pos

The current position within the byte array.

#### mark

    protected int mark

The current mark position. Initially set to 0 or the `offset` parameter within the constructor.

#### count

    protected int count

The total number of bytes initially available in the byte array `buf`.

### Constructor Detail

#### FastByteArrayInputStream

    public FastByteArrayInputStream(byte[] buf)

Constructs a new `ByteArrayInputStream` on the byte array `buf`.

Parameters:
  `buf` - the byte array to stream over.

#### FastByteArrayInputStream

    public FastByteArrayInputStream(byte[] buf,
                                    int offset,
                                    int length)

Constructs a new `ByteArrayInputStream` on the byte array `buf` with the initial position set to `offset` and the number of bytes available set to `offset` + `length`.

Parameters:
  `buf` - the byte array to stream over.
  `offset` - the initial position in `buf` to start streaming from.
  `length` - the number of bytes available for streaming.

### Method Detail

#### available

    public int available()

Returns the number of bytes that are available before this stream will block. This method returns the number of bytes yet to be read from the source byte array.

Overrides:
  `available` in class `java.io.InputStream`
Returns:
  the number of bytes available before blocking.

#### close

    public void close()
               throws java.io.IOException

Closes this stream and frees resources associated with this stream.

Specified by:
  `close` in interface `java.io.Closeable`
Specified by:
  `close` in interface `java.lang.AutoCloseable`
Overrides:
  `close` in class `java.io.InputStream`
Throws:
  `java.io.IOException` - if an I/O error occurs while closing this stream.

#### mark

    public void mark(int readlimit)

Sets a mark position in this ByteArrayInputStream. The parameter `readlimit` is ignored. Sending `reset()` will reposition the stream back to the marked position.

Overrides:
  `mark` in class `java.io.InputStream`
Parameters:
  `readlimit` - ignored.
See Also:
  `markSupported()`, `reset()`

#### markSupported

    public boolean markSupported()

Indicates whether this stream supports the `mark()` and `reset()` methods. Returns `true` since this class supports these methods.

Overrides:
  `markSupported` in class `java.io.InputStream`
Returns:
  always `true`.
See Also:
  `mark(int)`, `reset()`

#### read

    public int read()

Reads a single byte from the source byte array and returns it as an integer in the range from 0 to 255. Returns -1 if the end of the source array has been reached.

Specified by:
  `read` in class `java.io.InputStream`
Returns:
  the byte read or -1 if the end of this stream has been reached.

#### read

    public int read(byte[] b,
                    int offset,
                    int length)

Reads at most `len` bytes from this stream and stores them in byte array `b` starting at `offset`. This implementation reads bytes from the source byte array.

Overrides:
  `read` in class `java.io.InputStream`
Parameters:
  `b` - the byte array in which to store the bytes read.
  `offset` - the initial position in `b` to store the bytes read from this stream.
  `length` - the maximum number of bytes to store in `b`.
Returns:
  the number of bytes actually read or -1 if no bytes were read and the end of the stream was encountered.
Throws:
  `java.lang.IndexOutOfBoundsException` - if `offset < 0` or `length < 0`, or if `offset + length` is greater than the size of `b`.
  `java.lang.NullPointerException` - if `b` is `null`.

#### reset

    public void reset()

Resets this stream to the last marked location. This implementation resets the position to either the marked position, the start position supplied in the constructor or 0 if neither has been provided.

Overrides:
  `reset` in class `java.io.InputStream`
See Also:
  `mark(int)`

#### skip

    public long skip(long n)

Skips `count` number of bytes in this InputStream. Subsequent `read()`s will not return these bytes unless `reset()` is used. This implementation skips `count` number of bytes in the target stream. It does nothing and returns 0 if `n` is negative.

Overrides:
  `skip` in class `java.io.InputStream`
Parameters:
  `n` - the number of bytes to skip.
Returns:
  the number of bytes actually skipped.