ParsableBitArray

Kotlin |Java

@UnstableApi
@CheckReturnValue
public final class ParsableBitArray

Wraps a byte array, providing methods that allow it to be read as a bitstream.

Summary

Public fields
`byte[]`	`data`

Public constructors
`ParsableBitArray()` Creates a new instance that initially has no backing data.
`ParsableBitArray(byte[] data)` Creates a new instance that wraps an existing array.
`ParsableBitArray(byte[] data, int limit)` Creates a new instance that wraps an existing array.

Public methods
`int`	`bitsLeft()` Returns the number of bits yet to be read.
`void`	`byteAlign()` Aligns the position to the next byte boundary.
`int`	`getBytePosition()` Returns the current byte offset.
`int`	`getPosition()` Returns the current bit offset.
`void`	`putInt(int value, int numBits)` Overwrites `numBits` from this array using the `numBits` least significant bits from `value`.
`boolean`	`readBit()` Reads a single bit.
`int`	`readBits(int numBits)` Reads up to 32 bits.
`void`	`readBits(byte[] buffer, int offset, int numBits)` Reads `numBits` bits into `buffer`.
`long`	`readBitsToLong(int numBits)` Reads up to 64 bits.
`void`	`readBytes(byte[] buffer, int offset, int length)` Reads the next `length` bytes into `buffer`.
`String`	`readBytesAsString(int length)` Reads the next `length` bytes as a UTF-8 string.
`String`	`readBytesAsString(int length, Charset charset)` Reads the next `length` bytes as a string encoded in `Charset`.
`void`	`reset(byte[] data)` Updates the instance to wrap `data`, and resets the position to zero.
`void`	`reset(ParsableByteArray parsableByteArray)` Sets this instance's data, position and limit to match the provided `parsableByteArray`.
`void`	`reset(byte[] data, int limit)` Updates the instance to wrap `data`, and resets the position to zero.
`void`	`setPosition(int position)` Sets the current bit offset.
`void`	`skipBit()` Skips a single bit.
`void`	`skipBits(int numBits)` Skips bits and moves current reading position forward.
`void`	`skipBytes(int length)` Skips the next `length` bytes.

Public fields

data

public byte[] data

Public constructors

ParsableBitArray

public ParsableBitArray()

Creates a new instance that initially has no backing data.

ParsableBitArray

public ParsableBitArray(byte[] data)

Creates a new instance that wraps an existing array.

Parameters
`byte[] data`	The data to wrap.

ParsableBitArray

public ParsableBitArray(byte[] data, int limit)

Creates a new instance that wraps an existing array.

Parameters
`byte[] data`	The data to wrap.
`int limit`	The limit in bytes.

Public methods

bitsLeft

public int bitsLeft()

Returns the number of bits yet to be read.

byteAlign

public void byteAlign()

Aligns the position to the next byte boundary. Does nothing if the position is already aligned.

getBytePosition

public int getBytePosition()

Returns the current byte offset. Must only be called when the position is byte aligned.

Throws
`java.lang.IllegalStateException`	If the position isn't byte aligned.

getPosition

public int getPosition()

Returns the current bit offset.

putInt

public void putInt(int value, int numBits)

Overwrites numBits from this array using the numBits least significant bits from value. Bits are written in order from most significant to least significant. The read position is advanced by numBits.

Parameters
`int value`	The integer whose `numBits` least significant bits are written into `data`.
`int numBits`	The number of bits to write.

readBit

public boolean readBit()

Reads a single bit.

Returns
`boolean`	Whether the bit is set.

readBits

public int readBits(int numBits)

Reads up to 32 bits.

Parameters
`int numBits`	The number of bits to read.

Returns
`int`	An integer whose bottom `numBits` bits hold the read data.

readBits

public void readBits(byte[] buffer, int offset, int numBits)

Reads numBits bits into buffer.

Parameters
`byte[] buffer`	The array into which the read data should be written. The trailing `numBits % 8` bits are written into the most significant bits of the last modified `buffer` byte. The remaining ones are unmodified.
`int offset`	The offset in `buffer` at which the read data should be written.
`int numBits`	The number of bits to read.

readBitsToLong

public long readBitsToLong(int numBits)

Reads up to 64 bits.

Parameters
`int numBits`	The number of bits to read.

Returns
`long`	A long whose bottom `numBits` bits hold the read data.

readBytes

public void readBytes(byte[] buffer, int offset, int length)

Reads the next length bytes into buffer. Must only be called when the position is byte aligned.

Parameters
`byte[] buffer`	The array into which the read data should be written.
`int offset`	The offset in `buffer` at which the read data should be written.
`int length`	The number of bytes to read.

Throws
`java.lang.IllegalStateException`	If the position isn't byte aligned.

See also
`arraycopy`

readBytesAsString

public String readBytesAsString(int length)

Reads the next length bytes as a UTF-8 string. Must only be called when the position is byte aligned.

Parameters
`int length`	The number of bytes to read.

Returns
`String`	The string encoded by the bytes in UTF-8.

readBytesAsString

public String readBytesAsString(int length, Charset charset)

Reads the next length bytes as a string encoded in Charset. Must only be called when the position is byte aligned.

Parameters
`int length`	The number of bytes to read.
`Charset charset`	The character set of the encoded characters.

Returns
`String`	The string encoded by the bytes in the specified character set.

reset

public void reset(byte[] data)

Updates the instance to wrap data, and resets the position to zero.

Parameters
`byte[] data`	The array to wrap.

reset

public void reset(ParsableByteArray parsableByteArray)

Sets this instance's data, position and limit to match the provided parsableByteArray. Any modifications to the underlying data array will be visible in both instances

Parameters
`ParsableByteArray parsableByteArray`	The `ParsableByteArray`.

reset

public void reset(byte[] data, int limit)

Updates the instance to wrap data, and resets the position to zero.

Parameters
`byte[] data`	The array to wrap.
`int limit`	The limit in bytes.

setPosition

public void setPosition(int position)

Sets the current bit offset.

Parameters
`int position`	The position to set.

skipBit

public void skipBit()

Skips a single bit.

skipBits

public void skipBits(int numBits)

Skips bits and moves current reading position forward.

Parameters
`int numBits`	The number of bits to skip.

skipBytes

public void skipBytes(int length)

Skips the next length bytes. Must only be called when the position is byte aligned.

Parameters
`int length`	The number of bytes to read.

Throws
`java.lang.IllegalStateException`	If the position isn't byte aligned.