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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package java.lang;

/**
 * An inline class implements the {@code NonTearable} interface to
 * request that the JVM take extra care to avoid structure tearing
 * when loading or storing any value of the class to a field or array
 * element.  Normally, only fields declared {@code volatile} are
 * protected against structure tearing, but a class that implements
 * this marker interface will never have its values torn, even when
 * they are stored in array elements or in non-{@code volatile}
 * fields, and even when multiple threads perform racing writes.
 *
 * <p> An inline instance of multiple components is said to be "torn"
 * when two racing threads compete to update those components, and one
 * thread updates some components while another thread updates other
 * components.  The resulting inline value stored in the heap might be
 * a hybrid composed of field values from both racing writes.  In
 * extreme cases, this hybrid might be a value which is impossible
 * to construct by normal means, and if data integrity or security
 * depends on proper construction, the class should be declared as
 * implementing {@code NonTearable}.
 *
 * <p> Non-inline classes can implement {@code NonTearable}, and
 * interfaces can extend it, in the usual manner.  The special effect
 * on tearing applies to inline classes which implement this type,
 * either directly, or indirectly via a supertype.  Thus, it is not
 * correct to assume that an object {@code x} for which {@code x
 * instanceof NonTearable} is in fact an inline class instance.
 * It is also not correct to assume that tearing is possible for
 * classes which do not implement this marker interface, because
 * the JVM may elect to make some inline values non-tearable if
 * the cost of doing so is acceptable.  The effect of declaring
 * an inline type {@code NonTearable} is thus to override any
 * heuristic the JVM may employ to control tearing, in favor
 * of reliability, and possibly at the expense of performance.
 *
 * @author  John Rose
 * @since   (valhalla)
 */
public interface NonTearable {
}