io.nayuki.qrcodegen

Class BitBuffer

java.lang.Object

io.nayuki.qrcodegen.BitBuffer

All Implemented Interfaces:

Cloneable

public final class BitBuffer
extends Object
implements Cloneable

An appendable sequence of bits (0's and 1's).

Constructor Summary

Constructors

Constructor and Description
BitBuffer() Constructs an empty bit buffer (length 0).

Method Summary

Modifier and Type	Method and Description
void	appendBits(int val, int len) Appends the specified number of low bits of the specified value to this sequence.
void	appendData(QrSegment seg) Appends the bit data of the specified segment to this bit buffer.
int	bitLength() Returns the length of this sequence, which is a non-negative value.
BitBuffer	clone() Returns a copy of this bit buffer object.
int	getBit(int index) Returns the bit at the specified index, yielding 0 or 1.
byte[]	getBytes() Packs this buffer's bits into bytes in big endian, padding with '0' bit values, and returns the new array.

Methods inherited from class java.lang.Object

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

Constructor Detail

BitBuffer

public BitBuffer()

Constructs an empty bit buffer (length 0).

Method Detail

bitLength

public int bitLength()

Returns the length of this sequence, which is a non-negative value.

Returns:

the length of this sequence

getBit

public int getBit(int index)

Returns the bit at the specified index, yielding 0 or 1.

Parameters:

index - the index to get the bit at

Returns:

the bit at the specified index

Throws:

IndexOutOfBoundsException - if index < 0 or index ≥ bitLength

getBytes

public byte[] getBytes()

Packs this buffer's bits into bytes in big endian, padding with '0' bit values, and returns the new array.

Returns:

this sequence as a new array of bytes (not null)

appendBits

public void appendBits(int val,
                       int len)

Appends the specified number of low bits of the specified value to this sequence. Requires 0 ≤ val < 2^len.

Parameters:

val - the value to append

len - the number of low bits in the value to take

appendData

public void appendData(QrSegment seg)

Appends the bit data of the specified segment to this bit buffer.

Parameters:

seg - the segment whose data to append (not null)

Throws:

NullPointerException - if the segment is null

clone

public BitBuffer clone()

Returns a copy of this bit buffer object.

Overrides:

clone in class Object

Returns:

a copy of this bit buffer object