SparseBooleanArray

SparseBooleanArray

SparseBooleanArray ()

Creates a new SparseBooleanArray containing no mappings.

SparseBooleanArray

SparseBooleanArray (int initialCapacity)

Creates a new SparseBooleanArray containing no mappings that will not require any additional memory allocation to store the specified number of mappings. If you supply an initial capacity of 0, the sparse array will be initialized with a light-weight representation not requiring any additional array allocations.

Parameters
initialCapacity	int

append

void append (int key, 
                boolean value)

Puts a key/value pair into the array, optimizing for the case where the key is greater than all existing keys in the array.

Parameters
key	int
value	boolean

clear

void clear ()

Removes all key-value mappings from this SparseBooleanArray.

clone

SparseBooleanArray clone ()

Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object x, the expression:

 x.clone() != x

will be true, and that the expression:

 x.clone().getClass() == x.getClass()

will be true, but these are not absolute requirements. While it is typically the case that:

 x.clone().equals(x)

will be true, this is not an absolute requirement.

By convention, the returned object should be obtained by calling super.clone. If a class and all of its superclasses (except Object) obey this convention, it will be the case that x.clone().getClass() == x.getClass().

By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by super.clone before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by super.clone need to be modified.

The method clone for class Object performs a specific cloning operation. First, if the class of this object does not implement the interface Cloneable, then a CloneNotSupportedException is thrown. Note that all arrays are considered to implement the interface Cloneable and that the return type of the clone method of an array type T[] is T[] where T is any reference or primitive type. Otherwise, this method creates a new instance of the class of this object and initializes all its fields with exactly the contents of the corresponding fields of this object, as if by assignment; the contents of the fields are not themselves cloned. Thus, this method performs a "shallow copy" of this object, not a "deep copy" operation.

The class Object does not itself implement the interface Cloneable, so calling the clone method on an object whose class is Object will result in throwing an exception at run time.

Returns
SparseBooleanArray	a clone of this instance.

delete

void delete (int key)

Removes the mapping from the specified key, if there was any.

Parameters
key	int

equals

boolean equals (Object that)

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.

Parameters
that	Object: the reference object with which to compare.

Returns
boolean	true if this object is the same as the obj argument; false otherwise.

get

boolean get (int key)

Gets the boolean mapped from the specified key, or false if no such mapping has been made.

Parameters
key	int

Returns
boolean

get

boolean get (int key, 
                boolean valueIfKeyNotFound)

Gets the boolean mapped from the specified key, or the specified value if no such mapping has been made.

Parameters
key	int
valueIfKeyNotFound	boolean

Returns
boolean

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.)

Returns
int	a hash code value for this object.

indexOfKey

int indexOfKey (int key)

Returns the index for which keyAt(int) would return the specified key, or a negative number if the specified key is not mapped.

Parameters
key	int

Returns
int

indexOfValue

int indexOfValue (boolean value)

Returns an index for which valueAt(int) would return the specified key, or a negative number if no keys map to the specified value. Beware that this is a linear search, unlike lookups by key, and that multiple keys can map to the same value and this will find only one of them.

Parameters
value	boolean

Returns
int

keyAt

int keyAt (int index)

Given an index in the range 0...size()-1, returns the key from the indexth key-value mapping that this SparseBooleanArray stores.

The keys corresponding to indices in ascending order are guaranteed to be in ascending order, e.g., keyAt(0) will return the smallest key and keyAt(size()-1) will return the largest key.

Parameters
index	int

Returns
int

put

void put (int key, 
                boolean value)

Adds a mapping from the specified key to the specified value, replacing the previous mapping from the specified key if there was one.

Parameters
key	int
value	boolean

size

int size ()

Returns the number of key-value mappings that this SparseBooleanArray currently stores.

Returns
int

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 mappings.

Returns
String	a string representation of the object.

valueAt

boolean valueAt (int index)

Given an index in the range 0...size()-1, returns the value from the indexth key-value mapping that this SparseBooleanArray stores.

The values corresponding to indices in ascending order are guaranteed to be associated with keys in ascending order, e.g., valueAt(0) will return the value associated with the smallest key and valueAt(size()-1) will return the value associated with the largest key.

Parameters
index	int

Returns
boolean