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A set of utilities and tools to speed up and ease programming in Java.

There is a newer version: 0.5

package com.davidbracewell;

import com.davidbracewell.function.SerializableSupplier;
import lombok.NonNull;

import java.io.Serializable;
import java.util.concurrent.atomic.AtomicReference;

/**
 * Lazily create a value in a thread safe manner.
 *
 * @param  the type parameter
 * @author David B. Bracewell
 */
public final class Lazy implements Serializable {
  private static final long serialVersionUID = 1L;
  private volatile AtomicReference atomicReference = new AtomicReference<>(null);
  private volatile SerializableSupplier supplier;

  /**
   * Instantiates a new Lazy.
   *
   * @param supplier the supplier used to generate the value
   */
  public Lazy(@NonNull SerializableSupplier supplier) {
    this.supplier = supplier;
  }

  /**
   * Gets the value lazily
   *
   * @return the value
   */
  public T get() {
    atomicReference.compareAndSet(null, supplier.get());
    return atomicReference.get();
  }

}// END OF Lazy