Cached Object - A very simple caching class that will use the supplied update function whenever dirty to refresh its value.

CachedObject.java

import java.util.function.Supplier;

public class CachedObject<T> {
    private final Supplier<T> updateFunction;
    private T cachedValue;
    private boolean dirty = true;

    public CachedObject(Supplier<T> updateFunction) {
        this.updateFunction = updateFunction;
    }

    public T get() {
        if (dirty) {
            cachedValue = updateFunction.get();
            dirty = false;
        }

        return cachedValue;
    }

    public void setDirty() {
        dirty = true;
    }
}