Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 package com.sun.tools.javac.code;

 import java.lang.annotation.Annotation;

 import java.lang.annotation.Inherited;

 import java.lang.reflect.InvocationTargetException;

 import java.lang.reflect.Method;

 import javax.lang.model.AnnotatedConstruct;

 import com.sun.tools.javac.model.AnnotationProxyMaker;

 import com.sun.tools.javac.util.List;

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

 /**

  * Common super type for annotated constructs such as Types and Symbols.

  *

  * This class should *not* contain any fields since it would have a significant

  * impact on the javac memory footprint.

  *

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

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

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

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

  */

 public abstract class AnnoConstruct implements AnnotatedConstruct {

     // Override to enforce a narrower return type.

     @Override

     public abstract List<? extends Attribute.Compound> getAnnotationMirrors();

     // This method is part of the javax.lang.model API, do not use this in javac code.

     protected <A extends Annotation> Attribute.Compound getAttribute(Class<A> annoType) {

         String name = annoType.getName();

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

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

                 return anno;

         }

         return null;

     }

     @SuppressWarnings("unchecked")

     protected <A extends Annotation> A[] getInheritedAnnotations(Class<A> annoType) {

         return (A[]) java.lang.reflect.Array.newInstance(annoType, 0);  // annoType is the Class for A

     }

     // This method is part of the javax.lang.model API, do not use this in javac code.

     public <A extends Annotation> A[] getAnnotationsByType(Class<A> annoType) {

         if (!annoType.isAnnotation())

             throw new IllegalArgumentException("Not an annotation type: "

                                                + annoType);

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

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

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

         if (containerType == null) {

             A res = getAnnotation(annoType);

             int size = res == null ? 0 : 1;

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

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

             if (res != null)

                 arr[0] = res;

             return arr;

         }

         // So we have a containing type

         String annoTypeName = annoType.getName();

         String containerTypeName = containerType.getName();

         int directIndex = -1, containerIndex = -1;

         Attribute.Compound direct = null, container = null;

         // Find directly (explicit or implicit) present annotations

         int index = -1;

         for (Attribute.Compound attribute : getAnnotationMirrors()) {

             index++;

             if (attribute.type.tsym.flatName().contentEquals(annoTypeName)) {

                 directIndex = index;

                 direct = attribute;

             } else if(containerTypeName != null &&

                       attribute.type.tsym.flatName().contentEquals(containerTypeName)) {

                 containerIndex = index;

                 container = attribute;

             }

         }

         // Deal with inherited annotations

         if (direct == null && container == null &&

                 annoType.isAnnotationPresent(Inherited.class))

             return getInheritedAnnotations(annoType);

         // Pack them in an array

         Attribute[] contained0 = null;

         if (container != null)

             contained0 = unpackAttributes(container);

         ListBuffer<Attribute.Compound> compounds = new ListBuffer<>();

         if (contained0 != null) {

             for (Attribute a : contained0)

                 if (a instanceof Attribute.Compound)

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

         }

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

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

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

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

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

         int insert = -1;

         int length = arr.length;

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

             if (directIndex < containerIndex) {

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

                 insert = 1;

             } else {

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

                 insert = 0;

                 length--;

             }

         } else if (directIndex >= 0) {

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

             return arr;

         } else {

             // Only container

             insert = 0;

         }

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

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

         return arr;

     }

     // This method is part of the javax.lang.model API, do not use this in javac code.

     public <A extends Annotation> A getAnnotation(Class<A> annoType) {

         if (!annoType.isAnnotation())

             throw new IllegalArgumentException("Not an annotation type: " + annoType);

         Attribute.Compound c = getAttribute(annoType);

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

     }

     // Needed to unpack the runtime view of containing annotations

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

     private static final Method VALUE_ELEMENT_METHOD = initValueElementMethod();

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

         try {

             // Repeatable will not be available when bootstrapping on

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

             // literal for Repeatable.class.

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

         } catch (ClassNotFoundException | SecurityException e) {

             return null;

         }

     }

     private static Method initValueElementMethod() {

         if (REPEATABLE_CLASS == null)

             return null;

         Method m = null;

         try {

             m = REPEATABLE_CLASS.getMethod("value");

             if (m != null)

                 m.setAccessible(true);

             return m;

         } catch (NoSuchMethodException e) {

             return null;

         }

     }

     // Helper to getAnnotationsByType

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

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

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

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

         if (REPEATABLE_CLASS != null &&

             VALUE_ELEMENT_METHOD != null) {

             // Get the Repeatable instance on the annotations declaration

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

             if (repeatable != null) {

                 try {

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

                     // indicating the containing annotation type

                     @SuppressWarnings("unchecked")

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

                     if (containerType == null)

                         return null;

                     return containerType;

                 } catch (ClassCastException | IllegalAccessException | InvocationTargetException e) {

                     return null;

                 }

             }

         }

         return null;

     }

     // Helper to getAnnotationsByType

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

         // We now have an instance of the container,

         // unpack it returning an instance of the

         // contained type or null

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

     }

 }