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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.databind.io.json;
28  
29  import com.fasterxml.jackson.core.JsonFactory;
30  import com.fasterxml.jackson.core.JsonParser;
31  
32  import gov.nist.secauto.metaschema.core.configuration.IConfiguration;
33  import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItem;
34  import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItemFactory;
35  import gov.nist.secauto.metaschema.core.util.ObjectUtils;
36  import gov.nist.secauto.metaschema.databind.io.AbstractDeserializer;
37  import gov.nist.secauto.metaschema.databind.io.DeserializationFeature;
38  import gov.nist.secauto.metaschema.databind.model.IAssemblyClassBinding;
39  import gov.nist.secauto.metaschema.databind.model.info.IDataTypeHandler;
40  
41  import java.io.IOException;
42  import java.io.Reader;
43  import java.net.URI;
44  
45  import edu.umd.cs.findbugs.annotations.NonNull;
46  
47  public class DefaultJsonDeserializer<CLASS>
48      extends AbstractDeserializer<CLASS> {
49    private JsonFactory jsonFactory;
50  
51    /**
52     * Construct a new JSON deserializer that will parse the bound class identified
53     * by the {@code classBinding}.
54     *
55     * @param classBinding
56     *          the bound class information for the Java type this deserializer is
57     *          operating on
58     */
59    public DefaultJsonDeserializer(@NonNull IAssemblyClassBinding classBinding) {
60      super(classBinding);
61    }
62  
63    /**
64     * Get a JSON factory instance.
65     * <p>
66     * This method can be used by sub-classes to create a customized factory
67     * instance.
68     *
69     * @return the factory
70     */
71    @NonNull
72    protected JsonFactory newJsonFactoryInstance() {
73      return JsonFactoryFactory.instance();
74    }
75  
76    /**
77     * Get the parser factory associated with this deserializer.
78     *
79     * @return the factory instance
80     */
81    @NonNull
82    protected JsonFactory getJsonFactory() {
83      synchronized (this) {
84        if (jsonFactory == null) {
85          jsonFactory = newJsonFactoryInstance();
86        }
87        assert jsonFactory != null;
88        return jsonFactory;
89      }
90    }
91  
92    /**
93     * Using the managed JSON factory, create a new JSON parser instance using the
94     * provided reader.
95     *
96     * @param reader
97     *          the reader for the parser to read data from
98     * @return the new parser
99     * @throws IOException
100    *           if an error occurred while creating the parser
101    */
102   @SuppressWarnings("resource") // reader resource not owned
103   @NonNull
104   protected final JsonParser newJsonParser(@NonNull Reader reader) throws IOException {
105     return ObjectUtils.notNull(getJsonFactory().createParser(reader));
106   }
107 
108   @SuppressWarnings("null")
109   @Override
110   protected INodeItem deserializeToNodeItemInternal(@NonNull Reader reader, @NonNull URI documentUri)
111       throws IOException {
112     INodeItem retval;
113     try (JsonParser jsonParser = newJsonParser(reader)) {
114       MetaschemaJsonReader parser = new MetaschemaJsonReader(jsonParser);
115       IAssemblyClassBinding classBinding = getClassBinding();
116       IConfiguration<DeserializationFeature<?>> configuration = getConfiguration();
117 
118       if (classBinding.isRoot()
119           && configuration.isFeatureEnabled(DeserializationFeature.DESERIALIZE_JSON_ROOT_PROPERTY)) {
120 
121         // now parse the root property
122         CLASS value = ObjectUtils.requireNonNull(parser.read(classBinding));
123 
124         // // we should be at the end object
125         // JsonUtil.assertCurrent(parser, JsonToken.END_OBJECT);
126         //
127         // // advance past the end object
128         // JsonToken end = parser.nextToken();
129 
130         retval = INodeItemFactory.instance().newDocumentNodeItem(classBinding, documentUri, value);
131       } else {
132         // Make a temporary data type handler for the top-level definition
133         IDataTypeHandler dataTypeHandler = IDataTypeHandler.newDataTypeHandler(classBinding);
134 
135         // read the top-level definition
136         CLASS value = dataTypeHandler.readItem(null, parser);
137 
138         retval = INodeItemFactory.instance().newAssemblyNodeItem(classBinding, documentUri, value);
139       }
140       return retval;
141     }
142   }
143 
144   @Override
145   public CLASS deserializeToValue(@NonNull Reader reader, @NonNull URI documentUri) throws IOException {
146     return INodeItem.toValue(deserializeToNodeItemInternal(reader, documentUri));
147   }
148 }