1 /* 2 * Copyright (c) 2004, 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.tools.apt.mirror.util; 27 28 29 import com.sun.mirror.declaration.*; 30 import com.sun.mirror.util.Declarations; 31 import com.sun.tools.apt.mirror.declaration.DeclarationImpl; 32 import com.sun.tools.apt.mirror.declaration.MethodDeclarationImpl; 33 import com.sun.tools.apt.mirror.util.DeclarationsImpl; 34 import com.sun.tools.apt.mirror.AptEnv; 35 import com.sun.tools.javac.code.*; 36 import com.sun.tools.javac.code.Symbol.*; 37 import com.sun.tools.javac.util.Context; 38 39 import static com.sun.tools.javac.code.Kinds.*; 40 41 42 /** 43 * Implementation of Declarations utility methods for annotation processors 44 */ 45 @SuppressWarnings("deprecation") 46 public class DeclarationsImpl implements Declarations { 47 48 private final AptEnv env; 49 50 51 private static final Context.Key<Declarations> declarationsKey = 52 new Context.Key<Declarations>(); 53 54 public static Declarations instance(Context context) { 55 Declarations instance = context.get(declarationsKey); 56 if (instance == null) { 57 instance = new DeclarationsImpl(context); 58 } 59 return instance; 60 } 61 62 private DeclarationsImpl(Context context) { 63 context.put(declarationsKey, this); 64 env = AptEnv.instance(context); 65 } 66 67 68 /** 69 * {@inheritDoc} 70 * See sections 8.3 and 8.4.6 of 71 * <cite>The Java™ Language Specification</cite> 72 */ 73 public boolean hides(MemberDeclaration sub, MemberDeclaration sup) { 74 Symbol hider = ((DeclarationImpl) sub).sym; 75 Symbol hidee = ((DeclarationImpl) sup).sym; 76 77 // Fields only hide fields; methods only methods; types only types. 78 // Names must match. Nothing hides itself (just try it). 79 if (hider == hidee || 80 hider.kind != hidee.kind || 81 hider.name != hidee.name) { 82 return false; 83 } 84 85 // Only static methods can hide other methods. 86 // Methods only hide methods with matching signatures. 87 if (hider.kind == MTH) { 88 if ((hider.flags() & Flags.STATIC) == 0 || 89 !env.jctypes.isSubSignature(hider.type, hidee.type)) { 90 return false; 91 } 92 } 93 94 // Hider must be in a subclass of hidee's class. 95 // Note that if M1 hides M2, and M2 hides M3, and M3 is accessible 96 // in M1's class, then M1 and M2 both hide M3. 97 ClassSymbol hiderClass = hider.owner.enclClass(); 98 ClassSymbol hideeClass = hidee.owner.enclClass(); 99 if (hiderClass == null || hideeClass == null || 100 !hiderClass.isSubClass(hideeClass, env.jctypes)) { 101 return false; 102 } 103 104 // Hidee must be accessible in hider's class. 105 // The method isInheritedIn is poorly named: it checks only access. 106 return hidee.isInheritedIn(hiderClass, env.jctypes); 107 } 108 109 /** 110 * {@inheritDoc} 111 * See section 8.4.6.1 of 112 * <cite>The Java™ Language Specification</cite> 113 */ 114 public boolean overrides(MethodDeclaration sub, MethodDeclaration sup) { 115 MethodSymbol overrider = ((MethodDeclarationImpl) sub).sym; 116 MethodSymbol overridee = ((MethodDeclarationImpl) sup).sym; 117 ClassSymbol origin = (ClassSymbol) overrider.owner; 118 119 return overrider.name == overridee.name && 120 121 // not reflexive as per JLS 122 overrider != overridee && 123 124 // we don't care if overridee is static, though that wouldn't 125 // compile 126 !overrider.isStatic() && 127 128 // overrider, whose declaring type is the origin, must be 129 // in a subtype of overridee's type 130 env.jctypes.asSuper(origin.type, overridee.owner) != null && 131 132 // check access and signatures; don't check return types 133 overrider.overrides(overridee, origin, env.jctypes, false); 134 } 135 }