Class BitArray


  • public class BitArray
    extends java.lang.Object
    A packed array of booleans.
    • Constructor Summary

      Constructors 
      Constructor Description
      BitArray​(boolean[] bits)
      Create a BitArray whose bits are those of the given array of Booleans.
      BitArray​(int length)
      Creates a BitArray of the specified size, initialized to zeros.
      BitArray​(int length, byte[] a)
      Creates a BitArray of the specified size, initialized from the specified byte array.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.Object clone()  
      boolean equals​(java.lang.Object obj)  
      boolean get​(int index)
      Returns the indexed bit in this BitArray.
      int hashCode()
      Returns a hash code value for this bit array.
      int length()
      Returns the length of this BitArray.
      void set​(int index, boolean value)
      Sets the indexed bit in this BitArray.
      boolean[] toBooleanArray()
      Return a boolean array with the same bit values a this BitArray.
      byte[] toByteArray()
      Returns a Byte array containing the contents of this BitArray.
      java.lang.String toString()
      Returns a string representation of this BitArray.
      • Methods inherited from class java.lang.Object

        finalize, getClass, notify, notifyAll, wait, wait, wait
    • Constructor Detail

      • BitArray

        public BitArray​(int length)
                 throws java.lang.IllegalArgumentException
        Creates a BitArray of the specified size, initialized to zeros.
        Throws:
        java.lang.IllegalArgumentException
      • BitArray

        public BitArray​(int length,
                        byte[] a)
                 throws java.lang.IllegalArgumentException
        Creates a BitArray of the specified size, initialized from the specified byte array. The most significant bit of a[0] gets index zero in the BitArray. The array a must be large enough to specify a value for every bit in the BitArray. In other words, 8*a.length >= length.
        Throws:
        java.lang.IllegalArgumentException
      • BitArray

        public BitArray​(boolean[] bits)
        Create a BitArray whose bits are those of the given array of Booleans.
    • Method Detail

      • get

        public boolean get​(int index)
                    throws java.lang.ArrayIndexOutOfBoundsException
        Returns the indexed bit in this BitArray.
        Throws:
        java.lang.ArrayIndexOutOfBoundsException
      • set

        public void set​(int index,
                        boolean value)
                 throws java.lang.ArrayIndexOutOfBoundsException
        Sets the indexed bit in this BitArray.
        Throws:
        java.lang.ArrayIndexOutOfBoundsException
      • length

        public int length()
        Returns the length of this BitArray.
      • toByteArray

        public byte[] toByteArray()
        Returns a Byte array containing the contents of this BitArray. The bit stored at index zero in this BitArray will be copied into the most significant bit of the zeroth element of the returned byte array. The last byte of the returned byte array will be contain zeros in any bits that do not have corresponding bits in the BitArray. (This matters only if the BitArray's size is not a multiple of 8.)
      • equals

        public boolean equals​(java.lang.Object obj)
        Overrides:
        equals in class java.lang.Object
      • toBooleanArray

        public boolean[] toBooleanArray()
        Return a boolean array with the same bit values a this BitArray.
      • hashCode

        public int hashCode()
        Returns a hash code value for this bit array.
        Overrides:
        hashCode in class java.lang.Object
        Returns:
        a hash code value for this bit array.
      • clone

        public java.lang.Object clone()
        Overrides:
        clone in class java.lang.Object
      • toString

        public java.lang.String toString()
        Returns a string representation of this BitArray.
        Overrides:
        toString in class java.lang.Object