com.holonplatform.core

Interface Initializer<T>

Type Parameters:

T - Type of the value to lazy initialize

All Known Implementing Classes:

DefaultInitializer

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Initializer<T>

Interface for lazy initialization of a generic value.

Since:

5.0.0

Method Summary

Modifier and Type	Method and Description
T	get() Gets the value, initializing it if the value is not already initialized before returning to caller.
static <T> T	init(T value, Supplier<T> initializer) Lazy initializing method using given initializer to initialize the value if given value is null.
static <T> Initializer<T>	using(Supplier<T> initializer) Create a new Initializer using given initializer Supplier for value initialization.

Method Detail

get

T get()

Gets the value, initializing it if the value is not already initialized before returning to caller.

Returns:

the (lazy initialized) value

using

static <T> Initializer<T> using(Supplier<T> initializer)

Create a new Initializer using given initializer Supplier for value initialization.

The returned Initializer is thread-safe, ensuring that the initializer Supplier is called exactly one time following one or several calls of get() by any number of threads.

Type Parameters:

T - Type of the value to lazy initialize

Parameters:

initializer - Supplier to initialize the value. Must never return null.

Returns:

A new Initializer instance

init

static <T> T init(T value,
                  Supplier<T> initializer)

Lazy initializing method using given initializer to initialize the value if given value is null.

Type Parameters:

T - Type of the value to lazy initialize

Parameters:

value - Value to return if not null

initializer - Supplier to initialize the value. Must never return null.

Returns:

The given value if not null, or the initialized value using Supplier.get() method of given initializer