| /* |
| * This file is part of the Jikes RVM project (http://jikesrvm.org). |
| * |
| * This file is licensed to You under the Common Public License (CPL); |
| * You may not use this file except in compliance with the License. You |
| * may obtain a copy of the License at |
| * |
| * http://www.opensource.org/licenses/cpl1.0.php |
| * |
| * See the COPYRIGHT.txt file distributed with this work for information |
| * regarding copyright ownership. |
| */ |
| package org.vmmagic; |
| |
| import java.lang.annotation.Retention; |
| import java.lang.annotation.RetentionPolicy; |
| import java.lang.annotation.Target; |
| import java.lang.annotation.ElementType; |
| import java.lang.annotation.Inherited; |
| |
| /** |
| * The Unboxed annotation marks a type as unboxed. Besides the primitive types, all Java values |
| * are boxed types. Conceptually, they are represented by a pointer to a heap object. However, |
| * an unboxed type is represented by the value itself. All methods on an unboxed type are |
| * {@link Intrinsic}s. |
| * |
| * <p>As an unboxed type is not a regular java object there are a few constraints on the way unboxed |
| * types are handled;</p> |
| * <ul> |
| * <li>All methods are {@link Intrinsic} and thus there can be no virtual methods.</li> |
| * <li>An unboxed type can not be synchronized on.</li> |
| * <li>An unboxed type has no hashcode.</li> |
| * <li>An unboxed type MUST NOT be passed where an object is expected or when two overloaded methods |
| * can only be distinguished by by Object vs unboxed parameter type.</li> |
| * </ul> |
| * |
| * <p>NOTE: At the current time the Unboxed annotation is only used for documentation |
| * purposes but in the near future it is expected that the semantics of the annotation will |
| * be enforced by the compiler.</p> |
| */ |
| @Retention(RetentionPolicy.RUNTIME) |
| @Target(ElementType.TYPE) |
| @Inherited |
| public @interface Unboxed { } |