How can deferred initialization of resources or components in a program be ensured?

Lazy initialization allows creating resources or components only at the moment of their first use, which saves memory and startup time.

In Java, this can be implemented in several ways:

• Using lazy loading with null check:

private Resource resource;

public Resource getResource() {
    if (resource == null) {
        resource = new Resource();
    }
    return resource;
}

• Using a wrapper class with an internal static class:

public class ResourceHolder {
    private static class LazyHolder {
        static final Resource INSTANCE = new Resource();
    }

    public static Resource getInstance() {
        return LazyHolder.INSTANCE;
    }
}

• Using java.util.concurrent.atomic.AtomicReference or other thread-safe mechanisms, if a multithreaded environment is required.

Thus, the resource is created only on the first call, which improves performance and saves resources.