public SafeTreeSet() {
    this(new TreeSet<E>());
  }

  public SafeTreeSet(Collection<? extends E> collection) {
    this(new TreeSet<E>(collection));
  }

  public SafeTreeSet(Comparator<? super E> comparator) {
    this(new TreeSet<E>(comparator));
  }

  public SafeTreeSet(SortedSet<E> set) {
    this(new TreeSet<E>(set));
  }

  private SafeTreeSet(NavigableSet<E> delegate) {

import java.util.SortedSet;
import java.util.TreeSet;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.function.BiConsumer;
import java.util.stream.Collector;
import java.util.stream.Stream;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@code Sets}.
 *
 * @author Kevin Bourrillion

dear!  I'd nearly forgotten that I've got to grow up again!  Let
me see--how IS it to be managed?  I suppose I ought to eat or
drink something or other; but the great question is, what?'

  The great question certainly was, what?  Alice looked all round
her at the flowers and the blades of grass, but she did not see
anything that looked like the right thing to eat or drink under

    assertTrue(ArbitraryInstances.get(TreeSet.class).isEmpty());
    assertTrue(ArbitraryInstances.get(TreeMap.class).isEmpty());
    assertFreshInstanceReturned(
        LinkedList.class,
        Deque.class,
        Queue.class,
        PriorityQueue.class,
        BitSet.class,
        TreeSet.class,
        TreeMap.class);
  }

  public void testGet_misc() {

      }
      return message.toString();
    }
  }

  /**
   * Internal Lock implementations implement the {@code CycleDetectingLock} interface, allowing the
   * detection logic to treat all locks in the same manner.
   */
  private interface CycleDetectingLock {

    /** @return the {@link LockGraphNode} associated with this lock. */
    LockGraphNode getLockGraphNode();

    return generateTreeSet(freshElement);
  }

  @Generates
  static <E extends Comparable<? super E>> TreeSet<E> generateTreeSet(E freshElement) {
    TreeSet<E> set = Sets.newTreeSet();
    set.add(freshElement);
    return set;
  }

  @Generates
  static <E extends Comparable<? super E>> ImmutableSortedSet<E> generateImmutableSortedSet(

=================

Thank you so much for wanting to contribute to Guava! Here are a few important
things you should know about contributing:

1.  API changes require discussion, use cases, etc. Code comes later.
2.  Pull requests are great for small fixes for bugs, documentation, etc.
3.  Pull requests are not merged directly into the master branch.
4.  Code contributions require signing a Google CLA.

API changes
-----------

 */

/*
 * Source:
 * http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/test/tck-jsr166e/AtomicDoubleArrayTest.java?revision=1.13
 * (Modified to adapt to guava coding conventions)
 */

package com.google.common.util.concurrent;

import static org.junit.Assert.assertThrows;

import java.util.Arrays;

/** Unit test for {@link AtomicDoubleArray}. */
public class AtomicDoubleArrayTest extends JSR166TestCase {

    assertEquals(Arrays.toString(VALUES), aa.toString());
    assertEquals("[]", new AtomicDoubleArray(0).toString());
    assertEquals("[]", new AtomicDoubleArray(new double[0]).toString());
  }

  /** compareAndSet treats +0.0 and -0.0 as distinct values */
  public void testDistinctZeros() {
    AtomicDoubleArray aa = new AtomicDoubleArray(SIZE);
    for (int i : new int[] {0, SIZE - 1}) {
      assertFalse(aa.compareAndSet(i, -0.0, 7.0));

        long halfSquare = sqrtFloor * sqrtFloor + sqrtFloor;
        /*
         * We wish to test whether or not x <= (sqrtFloor + 0.5)^2 = halfSquare + 0.25. Since both x
         * and halfSquare are integers, this is equivalent to testing whether or not x <=
         * halfSquare. (We have to deal with overflow, though.)
         *
         * If we treat halfSquare as an unsigned long, we know that