1 /*

     2  * Copyright 2003-2006 Sun Microsystems, Inc.  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.  Sun designates this

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

     9  * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package com.sun.tools.javac.comp;

    27 

    28 import com.sun.tools.javac.util.*;

    29 import com.sun.tools.javac.code.*;

    30 import com.sun.tools.javac.code.Symbol.*;

    31 import com.sun.tools.javac.tree.*;

    32 import com.sun.tools.javac.tree.JCTree.*;

    33 

    34 /** Enter annotations on symbols.  Annotations accumulate in a queue,

    35  *  which is processed at the top level of any set of recursive calls

    36  *  requesting it be processed.

    37  *

    38  *  <p><b>This is NOT part of any API supported by Sun Microsystems.  If

    39  *  you write code that depends on this, you do so at your own risk.

    40  *  This code and its internal interfaces are subject to change or

    41  *  deletion without notice.</b>

    42  */

    43 public class Annotate {

    44     protected static final Context.Key<Annotate> annotateKey =

    45         new Context.Key<Annotate>();

    46 

    47     public static Annotate instance(Context context) {

    48         Annotate instance = context.get(annotateKey);

    49         if (instance == null)

    50             instance = new Annotate(context);

    51         return instance;

    52     }

    53 

    54     final Attr attr;

    55     final TreeMaker make;

    56     final Log log;

    57     final Symtab syms;

    58     final Name.Table names;

    59     final Resolve rs;

    60     final Types types;

    61     final ConstFold cfolder;

    62     final Check chk;

    63 

    64     protected Annotate(Context context) {

    65         context.put(annotateKey, this);

    66         attr = Attr.instance(context);

    67         make = TreeMaker.instance(context);

    68         log = Log.instance(context);

    69         syms = Symtab.instance(context);

    70         names = Name.Table.instance(context);

    71         rs = Resolve.instance(context);

    72         types = Types.instance(context);

    73         cfolder = ConstFold.instance(context);

    74         chk = Check.instance(context);

    75     }

    76 

    77 /* ********************************************************************

    78  * Queue maintenance

    79  *********************************************************************/

    80 

    81     private int enterCount = 0;

    82 

    83     ListBuffer<Annotator> q = new ListBuffer<Annotator>();

    84 

    85     public void later(Annotator a) {

    86         q.append(a);

    87     }

    88 

    89     public void earlier(Annotator a) {

    90         q.prepend(a);

    91     }

    92 

    93     /** Called when the Enter phase starts. */

    94     public void enterStart() {

    95         enterCount++;

    96     }

    97 

    98     /** Called after the Enter phase completes. */

    99     public void enterDone() {

   100         enterCount--;

   101         flush();

   102     }

   103 

   104     public void flush() {

   105         if (enterCount != 0) return;

   106         enterCount++;

   107         try {

   108             while (q.nonEmpty())

   109                 q.next().enterAnnotation();

   110         } finally {

   111             enterCount--;

   112         }

   113     }

   114 

   115     /** A client that has annotations to add registers an annotator,

   116      *  the method it will use to add the annotation.  There are no

   117      *  parameters; any needed data should be captured by the

   118      *  Annotator.

   119      */

   120     public interface Annotator {

   121         void enterAnnotation();

   122         String toString();

   123     }

   124 

   125 

   126 /* ********************************************************************

   127  * Compute an attribute from its annotation.

   128  *********************************************************************/

   129 

   130     /** Process a single compound annotation, returning its

   131      *  Attribute. Used from MemberEnter for attaching the attributes

   132      *  to the annotated symbol.

   133      */

   134     Attribute.Compound enterAnnotation(JCAnnotation a,

   135                                        Type expected,

   136                                        Env<AttrContext> env) {

   137         // The annotation might have had its type attributed (but not checked)

   138         // by attr.attribAnnotationTypes during MemberEnter, in which case we do not

   139         // need to do it again.

   140         Type at = (a.annotationType.type != null ? a.annotationType.type

   141                   : attr.attribType(a.annotationType, env));

   142         a.type = chk.checkType(a.annotationType.pos(), at, expected);

   143         if (a.type.isErroneous())

   144             return new Attribute.Compound(a.type, List.<Pair<MethodSymbol,Attribute>>nil());

   145         if ((a.type.tsym.flags() & Flags.ANNOTATION) == 0) {

   146             log.error(a.annotationType.pos(),

   147                       "not.annotation.type", a.type.toString());

   148             return new Attribute.Compound(a.type, List.<Pair<MethodSymbol,Attribute>>nil());

   149         }

   150         List<JCExpression> args = a.args;

   151         if (args.length() == 1 && args.head.getTag() != JCTree.ASSIGN) {

   152             // special case: elided "value=" assumed

   153             args.head = make.at(args.head.pos).

   154                 Assign(make.Ident(names.value), args.head);

   155         }

   156         ListBuffer<Pair<MethodSymbol,Attribute>> buf =

   157             new ListBuffer<Pair<MethodSymbol,Attribute>>();

   158         for (List<JCExpression> tl = args; tl.nonEmpty(); tl = tl.tail) {

   159             JCExpression t = tl.head;

   160             if (t.getTag() != JCTree.ASSIGN) {

   161                 log.error(t.pos(), "annotation.value.must.be.name.value");

   162                 continue;

   163             }

   164             JCAssign assign = (JCAssign)t;

   165             if (assign.lhs.getTag() != JCTree.IDENT) {

   166                 log.error(t.pos(), "annotation.value.must.be.name.value");

   167                 continue;

   168             }

   169             JCIdent left = (JCIdent)assign.lhs;

   170             Symbol method = rs.resolveQualifiedMethod(left.pos(),

   171                                                       env,

   172                                                       a.type,

   173                                                       left.name,

   174                                                       List.<Type>nil(),

   175                                                       null);

   176             left.sym = method;

   177             left.type = method.type;

   178             if (method.owner != a.type.tsym)

   179                 log.error(left.pos(), "no.annotation.member", left.name, a.type);

   180             Type result = method.type.getReturnType();

   181             Attribute value = enterAttributeValue(result, assign.rhs, env);

   182             if (!method.type.isErroneous())

   183                 buf.append(new Pair<MethodSymbol,Attribute>

   184                            ((MethodSymbol)method, value));

   185         }

   186         return new Attribute.Compound(a.type, buf.toList());

   187     }

   188 

   189     Attribute enterAttributeValue(Type expected,

   190                                   JCExpression tree,

   191                                   Env<AttrContext> env) {

   192         if (expected.isPrimitive() || types.isSameType(expected, syms.stringType)) {

   193             Type result = attr.attribExpr(tree, env, expected);

   194             if (result.isErroneous())

   195                 return new Attribute.Error(expected);

   196             if (result.constValue() == null) {

   197                 log.error(tree.pos(), "attribute.value.must.be.constant");

   198                 return new Attribute.Error(expected);

   199             }

   200             result = cfolder.coerce(result, expected);

   201             return new Attribute.Constant(expected, result.constValue());

   202         }

   203         if (expected.tsym == syms.classType.tsym) {

   204             Type result = attr.attribExpr(tree, env, expected);

   205             if (result.isErroneous())

   206                 return new Attribute.Error(expected);

   207             if (TreeInfo.name(tree) != names._class) {

   208                 log.error(tree.pos(), "annotation.value.must.be.class.literal");

   209                 return new Attribute.Error(expected);

   210             }

   211             return new Attribute.Class(types,

   212                                        (((JCFieldAccess) tree).selected).type);

   213         }

   214         if ((expected.tsym.flags() & Flags.ANNOTATION) != 0) {

   215             if (tree.getTag() != JCTree.ANNOTATION) {

   216                 log.error(tree.pos(), "annotation.value.must.be.annotation");

   217                 expected = syms.errorType;

   218             }

   219             return enterAnnotation((JCAnnotation)tree, expected, env);

   220         }

   221         if (expected.tag == TypeTags.ARRAY) { // should really be isArray()

   222             if (tree.getTag() != JCTree.NEWARRAY) {

   223                 tree = make.at(tree.pos).

   224                     NewArray(null, List.<JCExpression>nil(), List.of(tree));

   225             }

   226             JCNewArray na = (JCNewArray)tree;

   227             if (na.elemtype != null) {

   228                 log.error(na.elemtype.pos(), "new.not.allowed.in.annotation");

   229                 return new Attribute.Error(expected);

   230             }

   231             ListBuffer<Attribute> buf = new ListBuffer<Attribute>();

   232             for (List<JCExpression> l = na.elems; l.nonEmpty(); l=l.tail) {

   233                 buf.append(enterAttributeValue(types.elemtype(expected),

   234                                                l.head,

   235                                                env));

   236             }

   237             return new Attribute.

   238                 Array(expected, buf.toArray(new Attribute[buf.length()]));

   239         }

   240         if (expected.tag == TypeTags.CLASS &&

   241             (expected.tsym.flags() & Flags.ENUM) != 0) {

   242             attr.attribExpr(tree, env, expected);

   243             Symbol sym = TreeInfo.symbol(tree);

   244             if (sym == null ||

   245                 TreeInfo.nonstaticSelect(tree) ||

   246                 sym.kind != Kinds.VAR ||

   247                 (sym.flags() & Flags.ENUM) == 0) {

   248                 log.error(tree.pos(), "enum.annotation.must.be.enum.constant");

   249                 return new Attribute.Error(expected);

   250             }

   251             VarSymbol enumerator = (VarSymbol) sym;

   252             return new Attribute.Enum(expected, enumerator);

   253         }

   254         if (!expected.isErroneous())

   255             log.error(tree.pos(), "annotation.value.not.allowable.type");

   256         return new Attribute.Error(attr.attribExpr(tree, env, expected));

   257     }

   258 }