| /******************************************************************************* |
| * Copyright (c) 2011 Stephan Herrmann. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Stephan Herrmann - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jdt.annotation; |
| |
| import static java.lang.annotation.ElementType.*; |
| import java.lang.annotation.*; |
| |
| /** |
| * <blockquote> |
| * This annotation is intended for use by the Eclipse Java Compiler in order to |
| * support intra-procedural null analysis. Please see the original |
| * <a href="http://bugs.eclipse.org/bugs/186342">Bug 186342- [compiler][null] Using annotations for null checking</a> |
| * and the <a href="http://wiki.eclipse.org/JDT_Core/Null_Analysis">Wiki page</a> |
| * for status and availability of the implementation of these analyses. |
| * </blockquote> |
| * <p> |
| * Qualifier for a type in a method signature or a local variable declaration. |
| * The entity (return value, parameter, local variable) whose type has this |
| * annotation can never have the value <code>null</code> at runtime. |
| * <p> |
| * This has two consequences: |
| * <ol> |
| * <li>Dereferencing the entity is safe, i.e., no <code>NullPointerException</code> can occur at runtime.</li> |
| * <li>An attempt to bind a <code>null</code> value to the entity is a compile time error.</li> |
| * </ol> |
| * For the second case diagnostics issued by the compiler should distinguish three situations: |
| * <ol> |
| * <li>Nullness of the value can be statically determined, the entity is definitely bound from either of: |
| * <ul><li>the value <code>null</code>, or</li> |
| * <li>an entity with a {@link Nullable @Nullable} type.</li></ul></li> |
| * <li>Nullness can not definitely be determined, because different code branches yield different results.</li> |
| * <li>Nullness can not be determined, because other program elements are involved for which |
| * null annotations are lacking.</li> |
| * </ol> |
| * </p> |
| * @author stephan |
| */ |
| @Retention(RetentionPolicy.CLASS) |
| @Target({METHOD,PARAMETER,LOCAL_VARIABLE}) |
| public @interface NonNull { |
| |
| } |
