Package org.apache.calcite.util

Class BitString

java.lang.Object

org.apache.calcite.util.BitString

public class BitString
extends java.lang.Object

String of bits.

A bit string logically consists of a set of '0' and '1' values, of a specified length. The length is preserved even if this means that the bit string has leading '0's.

You can create a bit string from a string of 0s and 1s (BitString(String, int) or createFromBitString(java.lang.String)), or from a string of hex digits (createFromHexString(java.lang.String)). You can convert it to a byte array (getAsByteArray()), to a bit string (toBitString()), or to a hex string (toHexString()). A utility method toByteArrayFromBitString(java.lang.String, int) converts a bit string directly to a byte array.

This class is immutable: once created, none of the methods modify the value.

Field Summary

Fields

Modifier and Type	Field	Description
private int	bitCount
private java.lang.String	bits

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BitString(java.lang.String bits, int bitCount)

Method Summary

Modifier and Type	Method	Description
static BitString	concat(java.util.List<BitString> args)	Concatenates some BitStrings.
static BitString	createFromBitString(java.lang.String s)	Creates a BitString representation out of a Bit String.
static BitString	createFromBytes(byte[] bytes)	Creates a BitString from an array of bytes.
static BitString	createFromHexString(java.lang.String s)	Creates a BitString representation out of a Hex String.
byte[]	getAsByteArray()
int	getBitCount()
java.lang.String	toBitString()	Returns this bit string as a bit string, such as "10110".
static byte[]	toByteArrayFromBitString(java.lang.String bits, int bitCount)	Converts a bit string to an array of bytes.
java.lang.String	toHexString()	Converts this bit string to a hex string, such as "7AB".
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

bits

private final java.lang.String bits

bitCount

private final int bitCount

Constructor Detail

BitString

protected BitString(java.lang.String bits,
                    int bitCount)

Method Detail

createFromHexString

public static BitString createFromHexString(java.lang.String s)

Creates a BitString representation out of a Hex String. Initial zeros are be preserved. Hex String is defined in the SQL standard to be a string with odd number of hex digits. An even number of hex digits is in the standard a Binary String.

Parameters:

s - a string, in hex notation

Throws:

java.lang.NumberFormatException - if s is invalid.

createFromBitString

public static BitString createFromBitString(java.lang.String s)

Creates a BitString representation out of a Bit String. Initial zeros are be preserved.

Parameters:

s - a string of 0s and 1s.

Throws:

java.lang.NumberFormatException - if s is invalid.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getBitCount

public int getBitCount()

getAsByteArray

public byte[] getAsByteArray()

toBitString

public java.lang.String toBitString()

Returns this bit string as a bit string, such as "10110".

toHexString

public java.lang.String toHexString()

Converts this bit string to a hex string, such as "7AB".

toByteArrayFromBitString

public static byte[] toByteArrayFromBitString(java.lang.String bits,
                                              int bitCount)

Converts a bit string to an array of bytes.

concat

public static BitString concat(java.util.List<BitString> args)

Concatenates some BitStrings. Concatenates all at once, not pairwise, to avoid string copies.

Parameters:

args - BitString[]

createFromBytes

public static BitString createFromBytes(byte[] bytes)

Creates a BitString from an array of bytes.

Parameters:

bytes - Bytes

Returns:

BitString