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package org.graalvm.compiler.phases.common;

import java.util.function.Supplier;

A Supplier which always returns the same value, computed from an other supplier on the first access.

This implementation is not thread-safe and assumes the underlying supplier does not return null. If the underlying supplier returns null it will be called on each access until it returns a non-null value.

/** * A {@link Supplier} which always returns the same value, computed from an other supplier on the * first access. * * <p> * This implementation is not thread-safe and assumes the underlying supplier does not return null. * If the underlying supplier returns null it will be called on each access until it returns a * non-null value. * </p> */
public class LazyValue<T> implements Supplier<T> { private final Supplier<T> supplier; private T value; public LazyValue(Supplier<T> supplier) { this.supplier = supplier; } @Override public T get() { if (value == null) { value = supplier.get(); } return value; } }