com.aol.cyclops.lambda.utils

Class Mutable<T>

java.lang.Object

com.aol.cyclops.lambda.utils.Mutable<T>

Type Parameters:

T - Type held inside closed var

All Implemented Interfaces:

java.util.function.Supplier<T>

public class Mutable<T>
extends java.lang.Object
implements java.util.function.Supplier<T>

Class that represents a Closed Variable In Java 8 because of the effectively final rule references to captured variables can't be changed. e.g.

 
 String var = "hello";
 Runnable r = () -> var ="world";
 

Won't compile because var is treated as if it is final. This can be 'worked around' by using a wrapping object or array. e.g.

 Mutable<String> var =  Mutable.of("hello");
 Runnable r = () -> var.set("world");
 

Constructor Summary

Constructors

Constructor and Description
Mutable()

Method Summary

Modifier and Type	Method and Description
T	get()
Mutable<T>	mutate(java.util.function.Function<T,T> varFn)
static <T> Mutable<T>	of(T var) Create a Mutable variable, which can be mutated inside a Closure e.g.
Mutable<T>	set(T var)

Methods inherited from class java.lang.Object

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

Constructor Detail

Mutable

public Mutable()

Method Detail

of

public static <T> Mutable<T> of(T var)

Create a Mutable variable, which can be mutated inside a Closure e.g.

   Mutable<Integer> num = Mutable.of(20);
   
   Stream.of(1,2,3,4).map(i->i*10).peek(i-> num.mutate(n->n+i)).foreach(System.out::println);
   
   System.out.println(num.get());
   //prints 120
  

Parameters:

var - Initial value of Mutable

Returns:

New Mutable instance

get

public T get()

Specified by:

get in interface java.util.function.Supplier<T>

Returns:

Current value

set

public Mutable<T> set(T var)

Parameters:

var - New value

Returns:

this object with mutated value

mutate

public Mutable<T> mutate(java.util.function.Function<T,T> varFn)

Parameters:

varFn - New value

Returns:

this object with mutated value