ArraySet

ArraySet

ArraySet ()

Create a new empty ArraySet. The default capacity of an array map is 0, and will grow once items are added to it.

ArraySet

ArraySet (int capacity)

Create a new ArraySet with a given initial capacity.

ArraySet

ArraySet (ArraySet<E> set)

Create a new ArraySet with the mappings from the given ArraySet.

add

boolean add (E value)

Adds the specified object to this set. The set is not modified if it already contains the object.

addAll

boolean addAll (Collection<? extends E> collection)

Perform an add(Object) of all values in collection

addAll

void addAll (ArraySet<? extends E> array)

Perform a add(Object) of all values in array

clear

void clear ()

Make the array map empty. All storage is released.

contains

boolean contains (Object key)

Check whether a value exists in the set.

containsAll

boolean containsAll (Collection<?> collection)

Determine if the array set contains all of the values in the given collection.

ensureCapacity

void ensureCapacity (int minimumCapacity)

Ensure the array map can hold at least minimumCapacity items.

equals

boolean equals (Object object)

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

This implementation returns false if the object is not a set, or if the sets have different sizes. Otherwise, for each value in this set, it checks to make sure the value also exists in the other set. If any value doesn't exist, the method returns false; otherwise, it returns true.

hashCode

int hashCode ()

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

The general contract of hashCode is:

• Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
• If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result.
• It is not required that if two objects are unequal according to the equals(java.lang.Object) method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the Java^TM programming language.)

indexOf

int indexOf (Object key)

Returns the index of a value in the set.

isEmpty

boolean isEmpty ()

Return true if the array map contains no items.

iterator

Iterator<E> iterator ()

Return an Iterator over all values in the set.

Note: this is a fairly inefficient way to access the array contents, it requires generating a number of temporary objects and allocates additional state information associated with the container that will remain for the life of the container.

remove

boolean remove (Object object)

Removes the specified object from this set.

removeAll

boolean removeAll (Collection<?> collection)

Remove all values in the array set that exist in the given collection.

removeAll

boolean removeAll (ArraySet<? extends E> array)

Perform a remove(Object) of all values in array

removeAt

E removeAt (int index)

Remove the key/value mapping at the given index.

retainAll

boolean retainAll (Collection<?> collection)

Remove all values in the array set that do not exist in the given collection.

size

int size ()

Return the number of items in this array map.

toArray

T[] toArray (T[] array)

Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array. If the collection fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this collection.

If this collection fits in the specified array with room to spare (i.e., the array has more elements than this collection), the element in the array immediately following the end of the collection is set to null. (This is useful in determining the length of this collection only if the caller knows that this collection does not contain any null elements.)

If this collection makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

Suppose x is a collection known to contain only strings. The following code can be used to dump the collection into a newly allocated array of String:

     String[] y = x.toArray(new String[0]);

toArray

Object[] toArray ()

Returns an array containing all of the elements in this collection. If this collection makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

The returned array will be "safe" in that no references to it are maintained by this collection. (In other words, this method must allocate a new array even if this collection is backed by an array). The caller is thus free to modify the returned array.

This method acts as bridge between array-based and collection-based APIs.

toString

String toString ()

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:

 getClass().getName() + '@' + Integer.toHexString(hashCode())
 

This implementation composes a string by iterating over its values. If this set contains itself as a value, the string "(this Set)" will appear in its place.

valueAt

E valueAt (int index)

Return the value at the given index in the array.