content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.instrumentation.api.internal;
  
  import java.lang.annotation.ElementType;
  import java.lang.annotation.Retention;
  import java.lang.annotation.RetentionPolicy;
  import java.lang.annotation.Target;
  
  /**
   * The field or method to which this annotation is applied can only be accessed when holding a
   * particular lock, which may be a built-in (synchronization) lock, or may be an explicit {@link
   * java.util.concurrent.locks.Lock}.
   *
   * <p>The argument determines which lock guards the annotated field or method:
   *
   * <ul>
   *   <li>this : The string literal "this" means that this field is guarded by the class in which it
   *       is defined.
   *   <li>class-name.this : For inner classes, it may be necessary to disambiguate 'this'; the
   *       class-name.this designation allows you to specify which 'this' reference is intended
   *   <li>itself : For reference fields only; the object to which the field refers.
   *   <li>field-name : The lock object is referenced by the (instance or static) field specified by
   *       field-name.
   *   <li>class-name.field-name : The lock object is reference by the static field specified by
   *       class-name.field-name.
   *   <li>method-name() : The lock object is returned by calling the named nil-ary method.
   *   <li>class-name.class : The Class object for the specified class should be used as the lock
   *       object.
   * </ul>
   *
   * <p>This annotation is similar to {@link javax.annotation.concurrent.GuardedBy} but has {@link
   * RetentionPolicy#SOURCE} so it is not in published artifacts. We only apply this to private
   * members, so there is no reason to publish them and we avoid requiring end users to have to depend
   * on the annotations in their own build. See the original <a
   * href="https://github.com/open-telemetry/opentelemetry-java/issues/2897">issue</a> for more info.
   *
   * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
   * at any time.
   */
  @Target({ElementType.FIELD, ElementType.METHOD})
  @Retention(RetentionPolicy.SOURCE)
  public @interface GuardedBy {
    /** The name of the object guarding the target. */
    String value();
  }
  