1 /* 2 * Copyright (c) 1997, 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 com.sun.istack.internal; 27 28 import java.lang.annotation.Documented; 29 import java.lang.annotation.Retention; 30 import java.lang.annotation.RetentionPolicy; 31 import java.lang.annotation.Target; 32 import java.lang.annotation.ElementType; 33 34 /** 35 * Designates that a field, return value, argument, or a variable is supposed 36 * to be an {@link String#intern() interned} string. 37 * 38 * <p> 39 * In many places in the istack, we assume Strings to be interned for 40 * the performance reason. Similarly, In many other places, we don't 41 * make such an assumption for the performance reason (because intern 42 * isn't free.) 43 * 44 * <p> 45 * Therefore, distinguishing which part is supposed to be interned and 46 * which part is supposed to be not is important. This annotation 47 * allows us to capture that in the code. 48 * 49 * @author Kohsuke Kawaguchi 50 */ 51 @Documented 52 @Retention(RetentionPolicy.CLASS) 53 @Target({ElementType.FIELD,ElementType.METHOD,ElementType.PARAMETER,ElementType.LOCAL_VARIABLE}) 54 public @interface Interned { 55 }