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1   /*
2    * Portions of this software was developed by employees of the National Institute
3    * of Standards and Technology (NIST), an agency of the Federal Government and is
4    * being made available as a public service. Pursuant to title 17 United States
5    * Code Section 105, works of NIST employees are not subject to copyright
6    * protection in the United States. This software may be subject to foreign
7    * copyright. Permission in the United States and in foreign countries, to the
8    * extent that NIST may hold copyright, to use, copy, modify, create derivative
9    * works, and distribute this software and its documentation without fee is hereby
10   * granted on a non-exclusive basis, provided that this notice and disclaimer
11   * of warranty appears in all copies.
12   *
13   * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
14   * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
15   * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
16   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
17   * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
18   * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
19   * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
20   * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
21   * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
22   * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
23   * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
24   * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
25   */
26  
27  package gov.nist.secauto.metaschema.schemagen;
28  
29  import gov.nist.secauto.metaschema.core.configuration.IConfiguration;
30  import gov.nist.secauto.metaschema.core.model.IAssemblyDefinition;
31  import gov.nist.secauto.metaschema.core.model.IDefinition;
32  import gov.nist.secauto.metaschema.core.model.IModule;
33  import gov.nist.secauto.metaschema.core.util.ObjectUtils;
34  import gov.nist.secauto.metaschema.schemagen.datatype.IDatatypeManager;
35  
36  import java.io.Writer;
37  import java.util.LinkedList;
38  import java.util.List;
39  import java.util.function.BiConsumer;
40  
41  import edu.umd.cs.findbugs.annotations.NonNull;
42  import edu.umd.cs.findbugs.annotations.Nullable;
43  
44  /**
45   * Thsi abstract class provides a common implementation shared by all schema
46   * generators.
47   *
48   * @param <T>
49   *          the writer type
50   * @param <D>
51   *          the {@link IDatatypeManager} type
52   * @param <S>
53   *          the {@link IGenerationState} type
54   */
55  public abstract class AbstractSchemaGenerator<
56      T extends AutoCloseable,
57      D extends IDatatypeManager,
58      S extends AbstractGenerationState<
59          T, D>>
60      implements ISchemaGenerator {
61  
62    /**
63     * Create a new writer to use to write the schema.
64     *
65     * @param out
66     *          the {@link Writer} to write the schema content to
67     * @return the schema writer
68     * @throws SchemaGenerationException
69     *           if an error occurred while creating the writer
70     */
71    @NonNull
72    protected abstract T newWriter(@NonNull Writer out);
73  
74    /**
75     * Create a new schema generation state object.
76     *
77     * @param module
78     *          the Metaschema module to generate the schema for
79     * @param schemaWriter
80     *          the writer to use to write the schema
81     * @param configuration
82     *          the generation configuration
83     * @return the schema generation state used for context and writing
84     * @throws SchemaGenerationException
85     *           if an error occurred while creating the generation state object
86     */
87    @NonNull
88    protected abstract S newGenerationState(
89        @NonNull IModule module,
90        @NonNull T schemaWriter,
91        @NonNull IConfiguration<SchemaGenerationFeature<?>> configuration);
92  
93    /**
94     * Called to generate the actual schema content.
95     *
96     * @param generationState
97     *          the generation state object
98     */
99    protected abstract void generateSchema(@NonNull S generationState);
100 
101   @Override
102   public void generateFromModule(
103       IModule metaschema,
104       Writer out,
105       IConfiguration<SchemaGenerationFeature<?>> configuration) {
106     // IInlineStrategy inlineStrategy =
107     // IInlineStrategy.newInlineStrategy(configuration);
108     try {
109       // avoid automatically closing streams not owned by the generator
110       @SuppressWarnings("PMD.CloseResource") T schemaWriter = newWriter(out);
111       S generationState = newGenerationState(metaschema, schemaWriter, configuration);
112       generateSchema(generationState);
113       generationState.flushWriter();
114     } catch (SchemaGenerationException ex) { // NOPMD avoid nesting same exception
115       throw ex;
116     } catch (Exception ex) { // NOPMD need to catch close exception
117       throw new SchemaGenerationException(ex);
118     }
119   }
120 
121   /**
122    * Determine the collection of root definitions.
123    *
124    * @param generationState
125    *          the schema generation state used for context and writing
126    * @param handler
127    *          a callback to execute on each identified root definition
128    * @return the list of identified root definitions
129    */
130   protected List<IAssemblyDefinition> analyzeDefinitions(
131       @NonNull S generationState,
132       @Nullable BiConsumer<ModuleIndex.DefinitionEntry, IDefinition> handler) {
133     // TODO: use of handler here is confusing and introduces side effects. Consider
134     // refactoring this in
135     // the caller
136 
137     List<IAssemblyDefinition> rootAssemblyDefinitions = new LinkedList<>();
138     for (ModuleIndex.DefinitionEntry entry : generationState.getMetaschemaIndex().getDefinitions()) {
139 
140       boolean referenced = entry.isReferenced();
141 
142       IDefinition definition = ObjectUtils.notNull(entry.getDefinition());
143       if (definition instanceof IAssemblyDefinition && ((IAssemblyDefinition) definition).isRoot()) {
144         // found root definition
145         IAssemblyDefinition assemblyDefinition = (IAssemblyDefinition) definition;
146         rootAssemblyDefinitions.add(assemblyDefinition);
147         if (!referenced) {
148           referenced = true;
149           entry.incrementReferenceCount();
150         }
151 
152       }
153 
154       if (!referenced) {
155         // skip unreferenced definitions
156         continue;
157       }
158 
159       if (handler != null) {
160         handler.accept(entry, definition);
161       }
162     }
163     return rootAssemblyDefinitions;
164   }
165 
166 }