Method Detail

• hashCode

  public static int hashCode(boolean value)

  Returns a hash code for value; equal to the result of invoking ((Boolean) value).hashCode().

  Parameters:

  value - a primitive boolean value

  Returns:

  a hash code for the value

• compare

  public static int compare(boolean a,
            boolean b)

  Compares the two specified boolean values in the standard way (false is considered less than true). The sign of the value returned is the same as that of ((Boolean) a).compareTo(b).

  Note for Java 7 and later: this method should be treated as deprecated; use the equivalent Boolean.compare(boolean, boolean) method instead.

  Parameters:

  a - the first boolean to compare

  b - the second boolean to compare

  Returns:

  a positive number if only a is true, a negative number if only b is true, or zero if a == b

• contains

  public static boolean contains(boolean[] array,
                 boolean target)

  Returns true if target is present as an element anywhere in array.

  Note: consider representing the array as a BitSet instead, replacing Booleans.contains(array, true) with !bitSet.isEmpty() and Booleans.contains(array, false) with bitSet.nextClearBit(0) == sizeOfBitSet.

  Parameters:

  array - an array of boolean values, possibly empty

  target - a primitive boolean value

  Returns:

  true if array[i] == target for some value of i

• indexOf

  public static int indexOf(boolean[] array,
            boolean target)

  Returns the index of the first appearance of the value target in array.

  Note: consider representing the array as a BitSet instead, and using BitSet.nextSetBit(int) or BitSet.nextClearBit(int).

  Parameters:

  array - an array of boolean values, possibly empty

  target - a primitive boolean value

  Returns:

  the least index i for which array[i] == target, or -1 if no such index exists.

• indexOf

  public static int indexOf(boolean[] array,
            boolean[] target)

  Returns the start position of the first occurrence of the specified target within array, or -1 if there is no such occurrence.

  More formally, returns the lowest index i such that java.util.Arrays.copyOfRange(array, i, i + target.length) contains exactly the same elements as target.

  Parameters:

  array - the array to search for the sequence target

  target - the array to search for as a sub-sequence of array

• lastIndexOf

  public static int lastIndexOf(boolean[] array,
                boolean target)

  Returns the index of the last appearance of the value target in array.

  Parameters:

  array - an array of boolean values, possibly empty

  target - a primitive boolean value

  Returns:

  the greatest index i for which array[i] == target, or -1 if no such index exists.

• concat

  public static boolean[] concat(boolean[]... arrays)

  Returns the values from each provided array combined into a single array. For example, concat(new boolean[] {a, b}, new boolean[] {}, new boolean[] {c} returns the array {a, b, c}.

  Parameters:

  arrays - zero or more boolean arrays

  Returns:

  a single array containing all the values from the source arrays, in order

• ensureCapacity

  public static boolean[] ensureCapacity(boolean[] array,
                         int minLength,
                         int padding)

  Returns an array containing the same values as array, but guaranteed to be of a specified minimum length. If array already has a length of at least minLength, it is returned directly. Otherwise, a new array of size minLength + padding is returned, containing the values of array, and zeroes in the remaining places.

  Parameters:

  array - the source array

  minLength - the minimum length the returned array must guarantee

  padding - an extra amount to "grow" the array by if growth is necessary

  Returns:

  an array containing the values of array, with guaranteed minimum length minLength

  Throws:

  IllegalArgumentException - if minLength or padding is negative

• join

  public static String join(String separator,
            boolean... array)

  Returns a string containing the supplied boolean values separated by separator. For example, join("-", false, true, false) returns the string "false-true-false".

  Parameters:

  separator - the text that should appear between consecutive values in the resulting string (but not at the start or end)

  array - an array of boolean values, possibly empty

• lexicographicalComparator

  public static Comparator<boolean[]> lexicographicalComparator()

  Returns a comparator that compares two boolean arrays lexicographically. That is, it compares, using compare(boolean, boolean)), the first pair of values that follow any common prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For example, [] < [false] < [false, true] < [true].

  The returned comparator is inconsistent with Object.equals(Object) (since arrays support only identity equality), but it is consistent with Arrays.equals(boolean[], boolean[]).

  Since:

  2.0

  See Also:

  Lexicographical order article at Wikipedia

• toArray

  public static boolean[] toArray(Collection<Boolean> collection)

  Copies a collection of Boolean instances into a new array of primitive boolean values.

  Elements are copied from the argument collection as if by collection.toArray(). Calling this method is as thread-safe as calling that method.

  Note: consider representing the collection as a BitSet instead.

  Parameters:

  collection - a collection of Boolean objects

  Returns:

  an array containing the same values as collection, in the same order, converted to primitives

  Throws:

  NullPointerException - if collection or any of its elements is null

• asList

  public static List<Boolean> asList(boolean... backingArray)

  Returns a fixed-size list backed by the specified array, similar to Arrays.asList(Object[]). The list supports List.set(int, Object), but any attempt to set a value to null will result in a NullPointerException.

  The returned list maintains the values, but not the identities, of Boolean objects written to or read from it. For example, whether list.get(0) == list.get(0) is true for the returned list is unspecified.

  Parameters:

  backingArray - the array to back the list

  Returns:

  a list view of the array

• countTrue

  @Beta
  public static int countTrue(boolean... values)

  Returns the number of values that are true.

  Since:

  16.0