1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/rt/emul/compact/src/main/java/java/lang/SafeVarargs.java	Tue Feb 26 16:54:16 2013 +0100
     1.3 @@ -0,0 +1,91 @@
     1.4 +/*
     1.5 + * Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved.
     1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     1.7 + *
     1.8 + * This code is free software; you can redistribute it and/or modify it
     1.9 + * under the terms of the GNU General Public License version 2 only, as
    1.10 + * published by the Free Software Foundation.  Oracle designates this
    1.11 + * particular file as subject to the "Classpath" exception as provided
    1.12 + * by Oracle in the LICENSE file that accompanied this code.
    1.13 + *
    1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
    1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    1.16 + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    1.17 + * version 2 for more details (a copy is included in the LICENSE file that
    1.18 + * accompanied this code).
    1.19 + *
    1.20 + * You should have received a copy of the GNU General Public License version
    1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
    1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    1.23 + *
    1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    1.25 + * or visit www.oracle.com if you need additional information or have any
    1.26 + * questions.
    1.27 + */
    1.28 +
    1.29 +package java.lang;
    1.30 +
    1.31 +import java.lang.annotation.*;
    1.32 +
    1.33 +/**
    1.34 + * A programmer assertion that the body of the annotated method or
    1.35 + * constructor does not perform potentially unsafe operations on its
    1.36 + * varargs parameter.  Applying this annotation to a method or
    1.37 + * constructor suppresses unchecked warnings about a
    1.38 + * <i>non-reifiable</i> variable arity (vararg) type and suppresses
    1.39 + * unchecked warnings about parameterized array creation at call
    1.40 + * sites.
    1.41 + *
    1.42 + * <p> In addition to the usage restrictions imposed by its {@link
    1.43 + * Target @Target} meta-annotation, compilers are required to implement
    1.44 + * additional usage restrictions on this annotation type; it is a
    1.45 + * compile-time error if a method or constructor declaration is
    1.46 + * annotated with a {@code @SafeVarargs} annotation, and either:
    1.47 + * <ul>
    1.48 + * <li>  the declaration is a fixed arity method or constructor
    1.49 + *
    1.50 + * <li> the declaration is a variable arity method that is neither
    1.51 + * {@code static} nor {@code final}.
    1.52 + *
    1.53 + * </ul>
    1.54 + *
    1.55 + * <p> Compilers are encouraged to issue warnings when this annotation
    1.56 + * type is applied to a method or constructor declaration where:
    1.57 + *
    1.58 + * <ul>
    1.59 + *
    1.60 + * <li> The variable arity parameter has a reifiable element type,
    1.61 + * which includes primitive types, {@code Object}, and {@code String}.
    1.62 + * (The unchecked warnings this annotation type suppresses already do
    1.63 + * not occur for a reifiable element type.)
    1.64 + *
    1.65 + * <li> The body of the method or constructor declaration performs
    1.66 + * potentially unsafe operations, such as an assignment to an element
    1.67 + * of the variable arity parameter's array that generates an unchecked
    1.68 + * warning.  Some unsafe operations do not trigger an unchecked
    1.69 + * warning.  For example, the aliasing in
    1.70 + *
    1.71 + * <blockquote><pre>
    1.72 + * &#64;SafeVarargs // Not actually safe!
    1.73 + * static void m(List&lt;String&gt;... stringLists) {
    1.74 + *   Object[] array = stringLists;
    1.75 + *   List&lt;Integer&gt; tmpList = Arrays.asList(42);
    1.76 + *   array[0] = tmpList; // Semantically invalid, but compiles without warnings
    1.77 + *   String s = stringLists[0].get(0); // Oh no, ClassCastException at runtime!
    1.78 + * }
    1.79 + * </pre></blockquote>
    1.80 + *
    1.81 + * leads to a {@code ClassCastException} at runtime.
    1.82 + *
    1.83 + * <p>Future versions of the platform may mandate compiler errors for
    1.84 + * such unsafe operations.
    1.85 + *
    1.86 + * </ul>
    1.87 + *
    1.88 + * @jls 4.7 Reifiable Types
    1.89 + * @jls 8.4.1 Formal Parameters
    1.90 + */
    1.91 +@Documented
    1.92 +@Retention(RetentionPolicy.RUNTIME)
    1.93 +@Target({ElementType.CONSTRUCTOR, ElementType.METHOD})
    1.94 +public @interface SafeVarargs {}