@ElementTypesAreNonnullByDefault
public class ArrayBasedCharEscaperTest extends TestCase {
  private static final ImmutableMap<Character, String> NO_REPLACEMENTS = ImmutableMap.of();
  private static final ImmutableMap<Character, String> SIMPLE_REPLACEMENTS =
      ImmutableMap.of(
          '\n', "<newline>",
          '\t', "<tab>",
          '&', "<and>");

  public void testSafeRange() throws IOException {

package com.google.common.collect.testing;

import com.google.common.annotations.GwtCompatible;
import java.util.Queue;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates queues, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestQueueGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override

import com.google.common.collect.Multiset;
import com.google.common.collect.testing.TestCollectionGenerator;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates multisets, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestMultisetGenerator<E extends @Nullable Object>
    extends TestCollectionGenerator<E> {

package com.google.common.collect.testing;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Colliders;
import java.util.List;

/**
 * A generator using sample elements whose hash codes all collide badly.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestCollidingSetGenerator implements TestSetGenerator<Object> {

 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Simple base class to verify that we handle generics correctly. */
@GwtCompatible
class Base implements Comparable<Base>, Serializable {
  private final String s;

  public Base(String s) {
    this.s = s;
  }

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Unhashables;
import java.util.Collection;
import java.util.List;

/**
 * Creates collections containing unhashable sample elements, to be tested.
 *
 * @author Regina O'Dell
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestUnhashableCollectionGenerator<T extends Collection<UnhashableObject>>

import junit.framework.AssertionFailedError;
import junit.framework.TestCase;

/**
 * Base class for JSR166 Junit TCK tests. Defines some constants, utility methods and classes, as
 * well as a simple framework for helping to make sure that assertions failing in generated threads
 * cause the associated test that generated them to itself fail (which JUnit does not otherwise
 * arrange). The rules for creating such tests are:
 *

  private MinimalIterable(Iterator<E> iterator) {
    this.iterator = iterator;
  }

  @Override
  public Iterator<E> iterator() {
    if (iterator == null) {
      // TODO: throw something else? Do we worry that people's code and tests
      // might be relying on this particular type of exception?
      throw new IllegalStateException();
    }
    try {
      return iterator;
    } finally {
      iterator = null;
    }
  }

import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A container class for the five sample elements we need for testing.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class SampleElements<E extends @Nullable Object> implements Iterable<E> {

import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A container class for the five sample elements we need for testing.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class SampleElements<E extends @Nullable Object> implements Iterable<E> {