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