Class Optional

java.lang.Object

org.apache.el.stream.Optional

public class Optional
extends Object

Represents an optional value that may or may not be present.

Method Summary

Modifier and Type	Method	Description
Object	get()	Returns the contained value, or throws an exception if empty.
void	ifPresent(LambdaExpression le)	If a value is present, invokes the given lambda with the value.
Object	orElse(Object other)	Returns the contained value, or the given default value if empty.
Object	orElseGet(Object le)	Returns the contained value, or the result of evaluating the given lambda if empty.

Methods inherited from class Object

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

Method Details

get

public Object get()
           throws ELException

Returns the contained value, or throws an exception if empty.

Returns:

The contained value

Throws:

ELException - if the value is not present

ifPresent

public void ifPresent(LambdaExpression le)

If a value is present, invokes the given lambda with the value.

Parameters:

le - The lambda expression to invoke

orElse

public Object orElse(Object other)

Returns the contained value, or the given default value if empty.

Parameters:

other - The default value

Returns:

The contained value or the default

orElseGet

public Object orElseGet(Object le)

Returns the contained value, or the result of evaluating the given lambda if empty.

Parameters:

le - The lambda expression or already-evaluated value

Returns:

The contained value or the result of the lambda