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1   /*
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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
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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   *
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24   */
25  
26  package com.sun.tools.internal.xjc.reader;
27  
28  import java.util.HashSet;
29  import java.util.List;
30  import java.util.Set;
31  
32  import javax.activation.MimeType;
33  
34  import com.sun.tools.internal.xjc.model.CElementPropertyInfo;
35  import static com.sun.tools.internal.xjc.model.CElementPropertyInfo.CollectionMode.*;
36  import com.sun.tools.internal.xjc.model.CReferencePropertyInfo;
37  import com.sun.tools.internal.xjc.model.CTypeRef;
38  import com.sun.tools.internal.xjc.model.Multiplicity;
39  import com.sun.tools.internal.xjc.model.nav.NType;
40  import com.sun.xml.internal.bind.v2.model.core.Element;
41  import com.sun.xml.internal.bind.v2.model.core.ID;
42  import java.math.BigInteger;
43  
44  /**
45   * Set of {@link Ref}.
46   *
47   * @author Kohsuke Kawaguchi
48   */
49  public final class RawTypeSet {
50  
51  
52      public final Set<Ref> refs;
53  
54      /**
55       * True if this type set can form references to types.
56       */
57      public final Mode canBeTypeRefs;
58  
59      /**
60       * The occurence of the whole references.
61       */
62      public final Multiplicity mul;
63  
64      // computed inside canBeTypeRefs()
65      private CElementPropertyInfo.CollectionMode collectionMode;
66  
67      /**
68       * Should be called from one of the raw type set builders.
69       */
70      public RawTypeSet( Set<Ref> refs, Multiplicity m ) {
71          this.refs = refs;
72          mul = m;
73          canBeTypeRefs = canBeTypeRefs();
74      }
75  
76      public CElementPropertyInfo.CollectionMode getCollectionMode() {
77          return collectionMode;
78      }
79  
80      public boolean isRequired() {
81          return mul.min.compareTo(BigInteger.ZERO) == 1;
82      }
83  
84  
85      /**
86       * Represents the possible binding option for this {@link RawTypeSet}.
87       */
88      public enum Mode {
89          /**
90           * This {@link RawTypeSet} can be either an reference property or
91           * an element property, and XJC recommends element property.
92           */
93          SHOULD_BE_TYPEREF(0),
94          /**
95           * This {@link RawTypeSet} can be either an reference property or
96           * an element property, and XJC recommends reference property.
97           */
98          CAN_BE_TYPEREF(1),
99          /**
100          * This {@link RawTypeSet} can be only bound to a reference property.
101          */
102         MUST_BE_REFERENCE(2);
103 
104         private final int rank;
105 
106         Mode(int rank) {
107            this.rank = rank;
108         }
109 
110         Mode or(Mode that) {
111             switch(Math.max(this.rank,that.rank)) {
112             case 0:     return SHOULD_BE_TYPEREF;
113             case 1:     return CAN_BE_TYPEREF;
114             case 2:     return MUST_BE_REFERENCE;
115             }
116             throw new AssertionError();
117         }
118     }
119 
120     /**
121      * Returns true if {@link #refs} can form refs of types.
122      *
123      * If there are multiple {@link Ref}s with the same type,
124      * we cannot make them into type refs. Or if any of the {@link Ref}
125      * says they cannot be in type refs, we cannot do that either.
126      *
127      * TODO: just checking if the refs are the same is not suffice.
128      * If two refs derive from each other, they cannot form a list of refs
129      * (because of a possible ambiguity).
130      */
131     private Mode canBeTypeRefs() {
132         Set<NType> types = new HashSet<NType>();
133 
134         collectionMode = mul.isAtMostOnce()?NOT_REPEATED:REPEATED_ELEMENT;
135 
136         // the way we compute this is that we start from the most optimistic value,
137         // and then gradually degrade as we find something problematic.
138         Mode mode = Mode.SHOULD_BE_TYPEREF;
139 
140         for( Ref r : refs ) {
141             mode = mode.or(r.canBeType(this));
142             if(mode== Mode.MUST_BE_REFERENCE)
143                 return mode;    // no need to continue the processing
144 
145             if(!types.add(r.toTypeRef(null).getTarget().getType()))
146                 return Mode.MUST_BE_REFERENCE;   // collision
147             if(r.isListOfValues()) {
148                 if(refs.size()>1 || !mul.isAtMostOnce())
149                     return Mode.MUST_BE_REFERENCE;   // restriction on @XmlList
150                 collectionMode = REPEATED_VALUE;
151             }
152         }
153         return mode;
154     }
155 
156 
157 
158 
159     public void addTo(CElementPropertyInfo prop) {
160         assert canBeTypeRefs!= Mode.MUST_BE_REFERENCE;
161         if(mul.isZero())
162             return; // the property can't have any value
163 
164         List<CTypeRef> dst = prop.getTypes();
165         for( Ref t : refs )
166             dst.add(t.toTypeRef(prop));
167     }
168 
169     public void addTo(CReferencePropertyInfo prop) {
170         if(mul.isZero())
171             return; // the property can't have any value
172         for( Ref t : refs )
173             t.toElementRef(prop);
174     }
175 
176     public ID id() {
177         for( Ref t : refs ) {
178             ID id = t.id();
179             if(id!=ID.NONE)    return id;
180         }
181         return ID.NONE;
182     }
183 
184     public MimeType getExpectedMimeType() {
185         for( Ref t : refs ) {
186             MimeType mt = t.getExpectedMimeType();
187             if(mt!=null)    return mt;
188         }
189         return null;
190     }
191 
192 
193     /**
194      * A reference to something.
195      *
196      * <p>
197      * A {@link Ref} can be either turned into {@link CTypeRef} to form
198      * an element property, or {@link Element} to form a reference property.
199      */
200     public static abstract class Ref {
201         /**
202          * @param ep
203          *      the property to which the returned {@link CTypeRef} will be
204          *      added to.
205          */
206         protected abstract CTypeRef toTypeRef(CElementPropertyInfo ep);
207         protected abstract void toElementRef(CReferencePropertyInfo prop);
208         /**
209          * Can this {@link Ref} be a type ref?
210          * @return false to veto.
211          * @param parent
212          */
213         protected abstract Mode canBeType(RawTypeSet parent);
214         protected abstract boolean isListOfValues();
215         /**
216          * When this {@link RawTypeSet} binds to a {@link CElementPropertyInfo},
217          * this method is used to determine if the property is ID or not.
218          */
219         protected abstract ID id();
220 
221         /**
222          * When this {@link RawTypeSet} binds to a {@link CElementPropertyInfo},
223          * this method is used to determine if the property has an associated expected MIME type or not.
224          */
225         protected MimeType getExpectedMimeType() { return null; }
226     }
227 }