import java.io.Serializable;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.GenericDeclaration;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Proxy;
import java.lang.reflect.Type;

import java.io.Reader;
import java.io.StringReader;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.math.BigDecimal;

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.util.concurrent.NullnessCasts.uncheckedNull;
import static java.lang.Integer.toHexString;
import static java.lang.System.identityHashCode;
import static java.util.Objects.requireNonNull;
import static java.util.concurrent.atomic.AtomicReferenceFieldUpdater.newUpdater;

  @CheckForNull
  public abstract V get(@CheckForNull Object key);

  /**
   * {@inheritDoc}
   *
   * <p>See <a
   * href="https://developer.android.com/reference/java/util/Map.html#getOrDefault%28java.lang.Object,%20V%29">{@code
   * Map.getOrDefault}</a>.
   *
   * @since 23.5 (but since 21.0 in the JRE <a
   *     href="https://github.com/google/guava#guava-google-core-libraries-for-java">flavor</a>).

import com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.concurrent.GuardedBy;
import java.lang.reflect.InvocationTargetException;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.BlockingQueue;

import java.io.Reader;
import java.io.StringReader;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.math.BigDecimal;

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.base;

import com.google.common.annotations.GwtCompatible;
import java.lang.ref.WeakReference;
import java.util.Locale;
import java.util.regex.Pattern;
import javax.annotation.CheckForNull;

/**
 * Methods factored out so that they can be emulated differently in GWT.
 *

import com.google.common.base.Joiner;
import com.google.common.base.Splitter;
import com.google.common.collect.ImmutableBiMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;
import java.lang.reflect.Field;
import java.util.List;
import junit.framework.TestCase;

/**
 * Tests for the HttpHeaders class.
 *
 * @author Kurt Alfred Kluever
 */
public class HttpHeadersTest extends TestCase {

import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.GenericDeclaration;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.math.BigInteger;

import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.GenericDeclaration;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.math.BigInteger;