com.azure.android.core.util

Class Option<T>

java.lang.Object

com.azure.android.core.util.Option<T>

Type Parameters:

T - The value type.

public final class Option<T>
extends java.lang.Object

The Option type to describe tri-state. Every Option instance is in one of the three states: a state representing a non-null-value, null-value, or no-value.

Method Summary

Modifier and Type	Method and Description
static <T> Option<T>	empty() Returns an Option with null-value.
boolean	equals(java.lang.Object obj) Indicates whether some other object is "equal to" this Option.
T	getValue() Gets the value in the Option.
int	hashCode() Returns hash code of the value this Option is initialized with or -1 if in uninitialized state.
boolean	isInitialized() Return true if this instance is initialized with a null-value or non-null-value, otherwise false.
static <T> Option<T>	of(T value) Returns an Option with the specified null-value or non-null-value.
static <T> Option<T>	uninitialized() Returns an Option instance with no-value.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Method Detail

of

public static <T> Option<T> of(T value)

Returns an Option with the specified null-value or non-null-value.

Type Parameters:

T - The value type.

Parameters:

value - the value.

Returns:

an Option with the value present.

empty

public static <T> Option<T> empty()

Returns an Option with null-value.

Option.empty() is a syntactic sugar for Option.of(null).

Type Parameters:

T - The value type.

Returns:

an Option with a null-value.

uninitialized

public static <T> Option<T> uninitialized()

Returns an Option instance with no-value.

Type Parameters:

T - Type of the non-existent value.

Returns:

An Option type with no-value.

isInitialized

public boolean isInitialized()

Return true if this instance is initialized with a null-value or non-null-value, otherwise false.

Returns:

true if a value has been initialized, otherwise false

getValue

public T getValue()

Gets the value in the Option.

Returns:

The null (null-value) or non-null-value that the Option is initialized with.

Throws:

java.util.NoSuchElementException - thrown if the Option is in no-value state.

equals

public boolean equals(java.lang.Object obj)

Indicates whether some other object is "equal to" this Option. The other object is considered equal if:

• it is also an Option and;
• both instances are not initialized or;
• both instances are initialized and values are "equal to" each other via equals().

Overrides:

equals in class java.lang.Object

Parameters:

obj - an object to be tested for equality

Returns:

{code true} if the other object is "equal to" this object otherwise false

hashCode

public int hashCode()

Returns hash code of the value this Option is initialized with or -1 if in uninitialized state.

The value 0 will be returned when initialized with null.

Overrides:

hashCode in class java.lang.Object

Returns:

hash code of the value this Option is initialized with or -1 if in uninitialized state.