1 /*

     2  * Copyright (c) 2005, 2013, 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 package com.sun.tools.javac.model;

    26 

    27 import java.lang.annotation.Annotation;

    28 import java.lang.annotation.Inherited;

    29 import java.lang.reflect.InvocationTargetException;

    30 import java.lang.reflect.Method;

    31 

    32 import com.sun.tools.javac.code.Attribute;

    33 import com.sun.tools.javac.code.Kinds;

    34 import com.sun.tools.javac.code.Symbol;

    35 import com.sun.tools.javac.code.Symbol.ClassSymbol;

    36 import com.sun.tools.javac.code.Type;

    37 import com.sun.tools.javac.code.Type.AnnotatedType;

    38 import com.sun.tools.javac.util.ListBuffer;

    39 import static com.sun.tools.javac.code.TypeTag.CLASS;

    40 

    41 /**

    42  * Utility methods for operating on annotated constructs.

    43  *

    44  * <p><b>This is NOT part of any supported API.

    45  * If you write code that depends on this, you do so at your own

    46  * risk.  This code and its internal interfaces are subject to change

    47  * or deletion without notice.</b></p>

    48  */

    49 public class JavacAnnoConstructs {

    50 

    51     // <editor-fold defaultstate="collapsed" desc="Symbols">

    52 

    53     /**

    54      * An internal-use utility that creates a runtime view of an

    55      * annotation. This is the implementation of

    56      * Element.getAnnotation(Class).

    57      */

    58     public static <A extends Annotation> A getAnnotation(Symbol annotated,

    59                                                          Class<A> annoType) {

    60         if (!annoType.isAnnotation())

    61             throw new IllegalArgumentException("Not an annotation type: "

    62                                                + annoType);

    63         Attribute.Compound c;

    64         if (annotated.kind == Kinds.TYP && annotated instanceof ClassSymbol) {

    65             c = getAttributeOnClass((ClassSymbol)annotated, annoType);

    66         } else {

    67             c = getAttribute(annotated, annoType);

    68         }

    69         return c == null ? null : AnnotationProxyMaker.generateAnnotation(c, annoType);

    70     }

    71 

    72     // Helper to getAnnotation[s]

    73     private static <A extends Annotation> Attribute.Compound getAttribute(Symbol annotated,

    74                                                                           Class<A> annoType) {

    75         String name = annoType.getName();

    76 

    77         for (Attribute.Compound anno : annotated.getRawAttributes()) {

    78             if (name.equals(anno.type.tsym.flatName().toString()))

    79                 return anno;

    80         }

    81 

    82         return null;

    83     }

    84 

    85     // Helper to getAnnotation[s]

    86     private static <A extends Annotation> Attribute.Compound getAttributeOnClass(ClassSymbol annotated,

    87                                                                 Class<A> annoType) {

    88         boolean inherited = annoType.isAnnotationPresent(Inherited.class);

    89         Attribute.Compound result = null;

    90         while (annotated.name != annotated.name.table.names.java_lang_Object) {

    91             result = getAttribute(annotated, annoType);

    92             if (result != null || !inherited)

    93                 break;

    94             Type sup = annotated.getSuperclass();

    95             if (!sup.hasTag(CLASS) || sup.isErroneous())

    96                 break;

    97             annotated = (ClassSymbol) sup.tsym;

    98         }

    99         return result;

   100     }

   101 

   102     /**

   103      * An internal-use utility that creates a runtime view of

   104      * annotations. This is the implementation of

   105      * Element.getAnnotations(Class).

   106      */

   107     public static <A extends Annotation> A[] getAnnotations(Symbol annotated,

   108                                                             Class<A> annoType) {

   109         if (!annoType.isAnnotation())

   110             throw new IllegalArgumentException("Not an annotation type: "

   111                                                + annoType);

   112         // If annoType does not declare a container this is equivalent to wrapping

   113         // getAnnotation(...) in an array.

   114         Class <? extends Annotation> containerType = getContainer(annoType);

   115         if (containerType == null) {

   116             A res = getAnnotation(annotated, annoType);

   117             int size;

   118             if (res == null) {

   119                 size = 0;

   120             } else {

   121                 size = 1;

   122             }

   123             @SuppressWarnings("unchecked") // annoType is the Class for A

   124             A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size);

   125             if (res != null)

   126                 arr[0] = res;

   127             return arr;

   128         }

   129 

   130         // So we have a containing type

   131         String name = annoType.getName();

   132         String annoTypeName = annoType.getSimpleName();

   133         String containerTypeName = containerType.getSimpleName();

   134         int directIndex = -1, containerIndex = -1;

   135         Attribute.Compound direct = null, container = null;

   136         Attribute.Compound[] rawAttributes = annotated.getRawAttributes().toArray(new Attribute.Compound[0]);

   137 

   138         // Find directly present annotations

   139         for (int i = 0; i < rawAttributes.length; i++) {

   140             if (annoTypeName.equals(rawAttributes[i].type.tsym.flatName().toString())) {

   141                 directIndex = i;

   142                 direct = rawAttributes[i];

   143             } else if(containerTypeName != null &&

   144                       containerTypeName.equals(rawAttributes[i].type.tsym.flatName().toString())) {

   145                 containerIndex = i;

   146                 container = rawAttributes[i];

   147             }

   148         }

   149 

   150         // Deal with inherited annotations

   151         if (annotated.kind == Kinds.TYP &&

   152                 (annotated instanceof ClassSymbol)) {

   153             ClassSymbol s = (ClassSymbol)annotated;

   154             if (direct == null && container == null) {

   155                 direct = getAttributeOnClass(s, annoType);

   156                 container = getAttributeOnClass(s, containerType);

   157 

   158                 // both are inherited and found, put container last

   159                 if (direct != null && container != null) {

   160                     directIndex = 0;

   161                     containerIndex = 1;

   162                 } else if (direct != null) {

   163                     directIndex = 0;

   164                 } else {

   165                     containerIndex = 0;

   166                 }

   167             } else if (direct == null) {

   168                 direct = getAttributeOnClass(s, annoType);

   169                 if (direct != null)

   170                     directIndex = containerIndex + 1;

   171             } else if (container == null) {

   172                 container = getAttributeOnClass(s, containerType);

   173                 if (container != null)

   174                     containerIndex = directIndex + 1;

   175             }

   176         }

   177 

   178         // Pack them in an array

   179         Attribute[] contained0 = new Attribute[0];

   180         if (container != null)

   181             contained0 = unpackAttributes(container);

   182         ListBuffer<Attribute.Compound> compounds = ListBuffer.lb();

   183         for (Attribute a : contained0)

   184             if (a instanceof Attribute.Compound)

   185                 compounds = compounds.append((Attribute.Compound)a);

   186         Attribute.Compound[] contained = compounds.toArray(new Attribute.Compound[0]);

   187 

   188         int size = (direct == null ? 0 : 1) + contained.length;

   189         @SuppressWarnings("unchecked") // annoType is the Class for A

   190         A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size);

   191 

   192         // if direct && container, which is first?

   193         int insert = -1;

   194         int length = arr.length;

   195         if (directIndex >= 0 && containerIndex >= 0) {

   196             if (directIndex < containerIndex) {

   197                 arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   198                 insert = 1;

   199             } else {

   200                 arr[arr.length - 1] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   201                 insert = 0;

   202                 length--;

   203             }

   204         } else if (directIndex >= 0) {

   205             arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   206             return arr;

   207         } else {

   208             // Only container

   209             insert = 0;

   210         }

   211 

   212         for (int i = 0; i + insert < length; i++)

   213             arr[insert + i] = AnnotationProxyMaker.generateAnnotation(contained[i], annoType);

   214 

   215         return arr;

   216     }

   217 

   218     // </editor-fold>

   219 

   220     // <editor-fold defaultstate="collapsed" desc="Types">

   221 

   222     /**

   223      * An internal-use utility that creates a runtime view of an

   224      * annotation. This is the implementation of

   225      * TypeMirror.getAnnotation(Class).

   226      */

   227     public static <A extends Annotation> A getAnnotation(AnnotatedType annotated, Class<A> annoType) {

   228         if (!annoType.isAnnotation())

   229             throw new IllegalArgumentException("Not an annotation type: "

   230                                                + annoType);

   231         Attribute.Compound c = getAttribute(annotated, annoType);

   232         return c == null ? null : AnnotationProxyMaker.generateAnnotation(c, annoType);

   233     }

   234 

   235     // Helper to getAnnotation[s]

   236     private static <A extends Annotation> Attribute.Compound getAttribute(Type annotated,

   237                                                                           Class<A> annoType) {

   238         String name = annoType.getName();

   239 

   240         for (Attribute.Compound anno : annotated.getAnnotationMirrors()) {

   241             if (name.equals(anno.type.tsym.flatName().toString()))

   242                 return anno;

   243         }

   244 

   245         return null;

   246     }

   247 

   248     /**

   249      * An internal-use utility that creates a runtime view of

   250      * annotations. This is the implementation of

   251      * TypeMirror.getAnnotationsByType(Class).

   252      */

   253     public static <A extends Annotation> A[] getAnnotationsByType(AnnotatedType annotated, Class<A> annoType) {

   254         if (!annoType.isAnnotation())

   255             throw new IllegalArgumentException("Not an annotation type: "

   256                                                + annoType);

   257         // If annoType does not declare a container this is equivalent to wrapping

   258         // getAnnotation(...) in an array.

   259         Class <? extends Annotation> containerType = getContainer(annoType);

   260         if (containerType == null) {

   261             A res = getAnnotation(annotated, annoType);

   262             int size;

   263             if (res == null) {

   264                 size = 0;

   265             } else {

   266                 size = 1;

   267             }

   268             @SuppressWarnings("unchecked") // annoType is the Class for A

   269             A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size);

   270             if (res != null)

   271                 arr[0] = res;

   272             return arr;

   273         }

   274 

   275         // So we have a containing type

   276         String name = annoType.getName();

   277         String annoTypeName = annoType.getSimpleName();

   278         String containerTypeName = containerType.getSimpleName();

   279         int directIndex = -1, containerIndex = -1;

   280         Attribute.Compound direct = null, container = null;

   281         Attribute.Compound[] rawAttributes = annotated.getAnnotationMirrors().toArray(new Attribute.Compound[0]);

   282 

   283         // Find directly present annotations

   284         for (int i = 0; i < rawAttributes.length; i++) {

   285             if (annoTypeName.equals(rawAttributes[i].type.tsym.flatName().toString())) {

   286                 directIndex = i;

   287                 direct = rawAttributes[i];

   288             } else if(containerTypeName != null &&

   289                       containerTypeName.equals(rawAttributes[i].type.tsym.flatName().toString())) {

   290                 containerIndex = i;

   291                 container = rawAttributes[i];

   292             }

   293         }

   294 

   295         // Pack them in an array

   296         Attribute[] contained0 = new Attribute[0];

   297         if (container != null)

   298             contained0 = unpackAttributes(container);

   299         ListBuffer<Attribute.Compound> compounds = ListBuffer.lb();

   300         for (Attribute a : contained0) {

   301             if (a instanceof Attribute.Compound)

   302                 compounds = compounds.append((Attribute.Compound)a);

   303         }

   304         Attribute.Compound[] contained = compounds.toArray(new Attribute.Compound[0]);

   305 

   306         int size = (direct == null ? 0 : 1) + contained.length;

   307         @SuppressWarnings("unchecked") // annoType is the Class for A

   308         A[] arr = (A[])java.lang.reflect.Array.newInstance(annoType, size);

   309 

   310         // if direct && container, which is first?

   311         int insert = -1;

   312         int length = arr.length;

   313         if (directIndex >= 0 && containerIndex >= 0) {

   314             if (directIndex < containerIndex) {

   315                 arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   316                 insert = 1;

   317             } else {

   318                 arr[arr.length - 1] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   319                 insert = 0;

   320                 length--;

   321             }

   322         } else if (directIndex >= 0) {

   323             arr[0] = AnnotationProxyMaker.generateAnnotation(direct, annoType);

   324             return arr;

   325         } else {

   326             // Only container

   327             insert = 0;

   328         }

   329 

   330         for (int i = 0; i + insert < length; i++)

   331             arr[insert + i] = AnnotationProxyMaker.generateAnnotation(contained[i], annoType);

   332 

   333         return arr;

   334     }

   335 

   336     // </editor-fold>

   337 

   338     // <editor-fold defaultstate="collapsed" desc="Container support">

   339 

   340     // Needed to unpack the runtime view of containing annotations

   341     private static final Class<? extends Annotation> REPEATABLE_CLASS = initRepeatable();

   342     private static final Method VALUE_ELEMENT_METHOD = initValueElementMethod();

   343 

   344     private static Class<? extends Annotation> initRepeatable() {

   345         try {

   346             // Repeatable will not be available when bootstrapping on

   347             // JDK 7 so use a reflective lookup instead of a class

   348             // literal for Repeatable.class.

   349             return Class.forName("java.lang.annotation.Repeatable").asSubclass(Annotation.class);

   350         } catch (ClassNotFoundException e) {

   351             return null;

   352         } catch (SecurityException e) {

   353             return null;

   354         }

   355     }

   356 

   357     private static Method initValueElementMethod() {

   358         if (REPEATABLE_CLASS == null)

   359             return null;

   360 

   361         Method m = null;

   362         try {

   363             m = REPEATABLE_CLASS.getMethod("value");

   364             if (m != null)

   365                 m.setAccessible(true);

   366             return m;

   367         } catch (NoSuchMethodException e) {

   368             return null;

   369         }

   370     }

   371 

   372     // Helper to getAnnotations

   373     private static Class<? extends Annotation> getContainer(Class<? extends Annotation> annoType) {

   374         // Since we can not refer to java.lang.annotation.Repeatable until we are

   375         // bootstrapping with java 8 we need to get the Repeatable annotation using

   376         // reflective invocations instead of just using its type and element method.

   377         if (REPEATABLE_CLASS != null &&

   378             VALUE_ELEMENT_METHOD != null) {

   379             // Get the Repeatable instance on the annotations declaration

   380             Annotation repeatable = (Annotation)annoType.getAnnotation(REPEATABLE_CLASS);

   381             if (repeatable != null) {

   382                 try {

   383                     // Get the value element, it should be a class

   384                     // indicating the containing annotation type

   385                     @SuppressWarnings("unchecked")

   386                     Class<? extends Annotation> containerType = (Class)VALUE_ELEMENT_METHOD.invoke(repeatable);

   387                     if (containerType == null)

   388                         return null;

   389 

   390                     return containerType;

   391                 } catch (ClassCastException e) {

   392                     return null;

   393                 } catch (IllegalAccessException e) {

   394                     return null;

   395                 } catch (InvocationTargetException e ) {

   396                     return null;

   397                 }

   398             }

   399         }

   400         return null;

   401     }

   402 

   403     // Helper to getAnnotations

   404     private static Attribute[] unpackAttributes(Attribute.Compound container) {

   405         // We now have an instance of the container,

   406         // unpack it returning an instance of the

   407         // contained type or null

   408         return ((Attribute.Array)container.member(container.type.tsym.name.table.names.value)).values;

   409     }

   410 

   411     // </editor-fold>

   412 }