BitField (Javadocs [I2P+ 2.13.0+] - API Version 0.9.70+)

java.lang.Object
- org.klomp.snark.BitField

```
public class BitField
extends Object
```
Container of a byte array representing set and unset bits for torrent piece availability.
This class manages a bit field where each bit represents whether a particular piece of a torrent is available (set) or not available (unset). It's used to:
- Track which pieces a peer has available
- Track which pieces the local client has downloaded
- Determine which pieces are still needed
- Optimize piece selection strategies
The bit field is stored efficiently in a byte array, with 8 bits per byte.

Constructor Summary

Constructors
Constructor and Description
`BitField(byte[] bitfield, int size)` Creates a new BitField that represents the given number of bits as set by the given byte array.
`BitField(int size)` Creates a new BitField that represents the given number of unset bits.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clear(int bit)` Sets the given bit to false.
`boolean`	`complete()` Returns true if all bits are set.
`int`	`count()` Returns the number of set bits.
`boolean`	`equals(Object o)` Compares this BitField to another object for equality.
`boolean`	`get(int bit)` Returns true if the bit is set or false if it is not.
`byte[]`	`getFieldBytes()` Returns the actual byte array used.
`int`	`hashCode()` Returns a hash code value for this BitField.
`void`	`set(int bit)` Sets the given bit to true.
`void`	`setAll()` Sets all bits to true.
`int`	`size()` Returns the size of the BitField.
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - BitField
```
public BitField(byte[] bitfield,
                int size)
```
    Creates a new BitField that represents the given number of bits as set by the given byte array. This will make a copy of the array. Extra bytes will be ignored.
    Parameters:
    bitfield - the byte array containing the bit field data
    size - the number of bits represented
    Throws:
    IndexOutOfBoundsException - if the byte array is not large enough
  - BitField
```
public BitField(int size)
```
    Creates a new BitField that represents the given number of unset bits.
    Parameters:
    size - the number of bits in the bit field
- Method Detail
  - clear
```
public void clear(int bit)
```
    Sets the given bit to false.
    Parameters:
    bit - the bit
    Throws:
    IndexOutOfBoundsException - if bit is smaller then zero or bigger then or equal to size
  - complete
```
public boolean complete()
```
    Returns true if all bits are set.
    Returns:
    true if all bits are set (bit field is complete), false otherwise
  - count
```
public int count()
```
    Returns the number of set bits.
    Returns:
    the count of bits that are set to true
  - equals
```
public boolean equals(Object o)
```
    Compares this BitField to another object for equality.
    Overrides:
    equals in class Object
    Parameters:
    o - the object to compare with
    Returns:
    true if the objects are equal, false otherwise
  - get
```
public boolean get(int bit)
```
    Returns true if the bit is set or false if it is not.
    Parameters:
    bit - the bit
    Returns:
    true if the bit is set, false otherwise
    Throws:
    IndexOutOfBoundsException - if bit is smaller then zero or bigger then or equal to size
  - getFieldBytes
```
public byte[] getFieldBytes()
```
    Returns the actual byte array used. Changes to this array affect this BitField. Note that some bits at the end of the byte array are supposed to be always unset if they represent bits bigger then the size of the bitfield.
    Caller should synchronize on this and copy!
    Returns:
    the internal byte array representing the bit field
  - hashCode
```
public int hashCode()
```
    Returns a hash code value for this BitField.
    Overrides:
    hashCode in class Object
    Returns:
    a hash code value for this BitField
  - set
```
public void set(int bit)
```
    Sets the given bit to true.
    Parameters:
    bit - the bit
    Throws:
    IndexOutOfBoundsException - if bit is smaller then zero or bigger then or equal to size
  - setAll
```
public void setAll()
```
    Sets all bits to true.
  - size
```
public int size()
```
    Returns the size of the BitField. The returned value is one bigger then the last valid bit number (since bit numbers are counted from zero).
    Returns:
    the number of bits in the bit field
  - toString
```
public String toString()
```
    Overrides:
    toString in class Object

Class BitField

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

BitField

BitField

Method Detail

clear

complete

count

equals

get

getFieldBytes

hashCode

set

setAll

size

toString