import java.lang.ref.WeakReference;
import org.checkerframework.checker.nullness.qual.*;

public class WeakIdentityPair<T1 extends Object> {

  private final WeakReference<T1> a;

  public WeakIdentityPair(T1 a) {
    this.a = new WeakReference<>(a);
  }

  public @Nullable T1 getA() {
    return a.get();
  }
}