/**
 * {@code Escaper} instances suitable for strings to be included in XML attribute values and
 * elements' text contents. When possible, avoid manual escaping by using templating systems and
 * high-level APIs that provide autoescaping. For example, consider <a
 * href="http://www.xom.nu/">XOM</a> or <a href="http://www.jdom.org/">JDOM</a>.
 *
 * <p><b>Note:</b> Currently the escapers provided by this class do not escape any characters

@GwtCompatible(emulated = true)
@ReflectionSupport(value = ReflectionSupport.Level.FULL)
@ElementTypesAreNonnullByDefault
// Some Android 5.0.x Samsung devices have bugs in JDK reflection APIs that cause
// getDeclaredField to throw a NoSuchFieldException when the field is definitely there.
// Since this class only needs CAS on one field, we can avoid this bug by extending AtomicReference

/** Collectors utilities for {@code common.collect} internals. */
@GwtCompatible
@ElementTypesAreNonnullByDefault
@SuppressWarnings({"AndroidJdkLibsChecker", "Java7ApiChecker"})
@IgnoreJRERequirement // used only from APIs with Java 8 types in them
// (not used publicly by guava-android as of this writing, but we include it in the jar as a test)
final class CollectCollectors {

   * Returns a default thread factory used to create new threads.
   *
   * <p>When running on AppEngine with access to <a
   * href="https://cloud.google.com/appengine/docs/standard/java/javadoc/">AppEngine legacy
   * APIs</a>, this method returns {@code ThreadManager.currentRequestThreadFactory()}. Otherwise,
   * it returns {@link Executors#defaultThreadFactory()}.
   *
   * @since 14.0
   */
  @J2ktIncompatible

   * illustrated <a
   * href="http://unicode.org/cldr/utility/list-unicodeset.jsp?a=%5Cp%7Bwhitespace%7D">here</a>.
   * This is not the same definition used by other Java APIs. (See a <a
   * href="https://goo.gl/Y6SLWx">comparison of several definitions of "whitespace"</a>.)
   *
   * <p>All Unicode White_Space characters are on the BMP and thus supported by this API.
   *

## IMPORTANT WARNINGS

1. APIs marked with the `@Beta` annotation at the class or method level
are subject to change. They can be modified in any way, or even
removed, at any time. If your code is a library itself (i.e. it is
used on the CLASSPATH of users outside your own control), you should
not use beta APIs, unless you [repackage] them. **If your

 * annotation implies nothing about the quality or performance of the API in question, only the fact
 * that it is not "API-frozen."
 *
 * <p>It is generally safe for <i>applications</i> to depend on beta APIs, at the cost of some extra
 * work during upgrades. However it is generally inadvisable for <i>libraries</i> (which get
 * included on users' CLASSPATHs, outside the library developers' control) to do so.
 *

  @SuppressWarnings({
    // We use this method only for cases in which we need to decompose to primitives.
    "GoodTime-ApiWithNumericTimeUnit",
    "GoodTime-DecomposeToPrimitive",
    // We use this method only from within APIs that require a Duration.
    "Java7ApiChecker",
  })
  @IgnoreJRERequirement
  static long toNanosSaturated(Duration duration) {
    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for

  @SuppressWarnings({
    // We use this method only for cases in which we need to decompose to primitives.
    "GoodTime-ApiWithNumericTimeUnit",
    "GoodTime-DecomposeToPrimitive",
    // We use this method only from within APIs that require a Duration.
    "Java7ApiChecker",
  })
  @IgnoreJRERequirement
  static long toNanosSaturated(Duration duration) {
    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for

   *   <li>{@link #JAVA_COMPILER}, while still listed as required as of Java 15, is typically not
   *       available even under older version.
   *   <li>Any property may be cleared through APIs like {@link System#clearProperty}.
   *   <li>Unusual environments like GWT may have their own special handling of system properties.
   * </ul>
   *