1 /* 2 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.lang; 27 28 import java.lang.annotation.*; 29 30 /** 31 * A programmer assertion that the body of the annotated method or 32 * constructor does not perform potentially unsafe operations on its 33 * varargs parameter. Applying this annotation to a method or 34 * constructor suppresses unchecked warnings about a 35 * <i>non-reifiable</i> variable-arity (vararg) type and suppresses 36 * unchecked warnings about parameterized array creation at call 37 * sites. 38 * 39 * <p> In addition to the usage restrictions imposed by its {@link 40 * Target @Target} meta-annotation, compilers are required to implement 41 * additional usage restrictions on this annotation type; it is a 42 * compile-time error if a method or constructor declaration is 43 * annotated with a {@code @SafeVarargs} annotation, and either: 44 45 * <ul> 46 * <li> the declaration is a fixed-arity method or constructor 47 * 48 * <li> the declaration is a variable-arity method that is neither 49 * {@code static} nor {@code final}. 50 * 51 * </ul> 52 * 53 * <p> Compilers are encouraged to issue warnings when this annotation 54 * type is applied to a method or constructor declaration where: 55 * 56 * <ul> 57 * 58 * <li> The variable-arity parameter has a reifiable element type, 59 * which includes primitive types, {@code Object}, and {@code String}. 60 * (The unchecked warnings this annotation type suppresses already do 61 * not occur for a reifiable element type.) 62 * 63 * <li> The body of the method or constructor declaration performs 64 * potentially unsafe operations, such as an assignment to an element 65 * of the variable-arity parameter's array that generates an unchecked 66 * warning. 67 * 68 * <p>Future versions of the platform may mandate compiler errors for 69 * such unsafe operations. 70 * 71 * </ul> 72 * 73 * @jls3 4.7 Reifiable Types 74 * @jls3 8.4.1 Formal Parameters 75 */ 76 @Documented 77 @Retention(RetentionPolicy.RUNTIME) 78 @Target({ElementType.CONSTRUCTOR, ElementType.METHOD}) 79 public @interface SafeVarargs {}