Each of the {@code Class} objects representing array types, - * primitive types, and {@code void} returns {@code this} to indicate - * that the represented entity belongs to the nest consisting only of - * itself, and is the nest host. - * - *
If there is a {@linkplain LinkageError linkage error} accessing - * the nest host, or if this class or interface is not enumerated as - * a member of the nest by the nest host, then it is considered to belong - * to its own nest and {@code this} is returned as the host. + * Every class and interface belongs to exactly one nest. * - *
If this class is a {@linkplain Class#isHiddenClass() hidden class} - * created by calling - * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...) - * Lookup::defineHiddenClass} with {@link MethodHandles.Lookup.ClassOption#NESTMATE - * NESTMATE} option, then the hidden class is added as a member to - * the nest of a {@linkplain MethodHandles.Lookup#lookupClass() lookup class} - * dynamically and it has the same nest host as the lookup class. - * - * @apiNote A {@code class} file of version 55.0 or greater may record the - * host of the nest to which it belongs by using the {@code NestHost} - * attribute (JVMS 4.7.28). Alternatively, a {@code class} file of - * version 55.0 or greater may act as a nest host by enumerating the nest's - * other members with the - * {@code NestMembers} attribute (JVMS 4.7.29). - * A {@code class} file of version 54.0 or lower does not use these - * attributes. + * If the nest host of this class or interface has previously + * been determined, then this method returns the nest host. + * If the nest host of this class or interface has + * not previously been determined, then this method determines the nest + * host using the algorithm of JVMS 5.4.4, and returns it. + * + * Often, a class or interface belongs to a nest consisting only of itself, + * in which case this method returns {@code this} to indicate that the class + * or interface is the nest host. + * + *
If this {@code Class} object represents a primitive type, an array type, + * or {@code void}, then this method returns {@code this}, + * indicating that the represented entity belongs to the nest consisting only of + * itself, and is the nest host. * * @return the nest host of this class or interface * * @throws SecurityException - * If the returned class is not the current class, and - * if a security manager, s, is present and the caller's - * class loader is not the same as or an ancestor of the class - * loader for the returned class and invocation of {@link - * SecurityManager#checkPackageAccess s.checkPackageAccess()} - * denies access to the package of the returned class + * If the returned class is not the current class, and + * if a security manager, s, is present and the caller's + * class loader is not the same as or an ancestor of the class + * loader for the returned class and invocation of {@link + * SecurityManager#checkPackageAccess s.checkPackageAccess()} + * denies access to the package of the returned class * @since 11 * @jvms 4.7.28 The {@code NestHost} Attribute * @jvms 4.7.29 The {@code NestMembers} Attribute @@ -4076,12 +4061,9 @@ Class host = this.nest; if (host == null) { host = getNestHost0(); - // if null then nest membership validation failed, so we - // act as-if we have no nest-host attribute - if (host == null || host == this) { + if (host == this) { return this.nest = this; } - this.nest = host; } // returning a different class requires a security check SecurityManager sm = System.getSecurityManager(); @@ -4089,7 +4071,7 @@ checkPackageAccess(sm, ClassLoader.getClassLoader(Reflection.getCallerClass()), true); } - return host; + return (this.nest = host); } // keep a strong reference to the nest host @@ -4125,46 +4107,45 @@ * Returns an array containing {@code Class} objects representing all the * classes and interfaces that are members of the nest to which the class * or interface represented by this {@code Class} object belongs. - * The {@linkplain #getNestHost() nest host} of that nest is the zeroth - * element of the array. Subsequent elements represent any classes or - * interfaces that are recorded by the nest host as being members of - * the nest; the order of such elements is unspecified. Duplicates are - * permitted. - * If the nest host of that nest does not enumerate any members, then the - * array has a single element containing {@code this}. * - *
Each of the {@code Class} objects representing array types, - * primitive types, and {@code void} returns an array containing only - * {@code this}. + * First, this method obtains the {@linkplain #getNestHost() nest host}, {@code H}, of the nest + * to which the class or interface represented by this {@code Class} object belongs. + * The zeroth element of the returned array is {@code H}. + * + * Then, for each class or interface {@code C} which is recorded by {@code H} as being a member + * of its nest, this method attempts to obtain the {@code Class} object for {@code C} + * (using {@linkplain #getClassLoader() the defining class loader} of the current {@code Class} object), + * and then obtains the {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs. + * The classes and interfaces which are recorded by {@code H} as being members of its nest, + * and for which {@code H} can be determined as their nest host, are indicated by subsequent elements + * of the returned array. The order of such elements is unspecified. + * Duplicates are permitted. * - *
This method validates that, for each class or interface which is - * recorded as a member of the nest by the nest host, that class or - * interface records itself as a member of that same nest. Any exceptions - * that occur during this validation are rethrown by this method. + *
If this {@code Class} object represents a primitive type, an array type, + * or {@code void}, then this method returns a single-element array containing + * {@code this}. * * @apiNote - * This method returns the nest members listed in the {@code NestMembers} - * attribute. The returned array does not include any hidden class that - * were added to the nest of this class via + * The returned array includes only the nest members recorded in the {@code NestMembers} + * attribute, and not any hidden classes that were added to the nest via * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...) * Lookup::defineHiddenClass}. * * @return an array of all classes and interfaces in the same nest as * this class * - * @throws LinkageError - * If there is any problem loading or validating a nest member or - * its nest host * @throws SecurityException - * If any returned class is not the current class, and - * if a security manager, s, is present and the caller's - * class loader is not the same as or an ancestor of the class - * loader for that returned class and invocation of {@link - * SecurityManager#checkPackageAccess s.checkPackageAccess()} - * denies access to the package of that returned class + * If any returned class is not the current class, and + * if a security manager, s, is present and the caller's + * class loader is not the same as or an ancestor of the class + * loader for that returned class and invocation of {@link + * SecurityManager#checkPackageAccess s.checkPackageAccess()} + * denies access to the package of that returned class * * @since 11 * @see #getNestHost() + * @jvms 4.7.28 The {@code NestHost} Attribute + * @jvms 4.7.29 The {@code NestMembers} Attribute */ @CallerSensitive public Class[] getNestMembers() {