JacksonJaxbJsonProvider默认对象映射器映射

Question

我使用此链接中的以下代码为我的一个数据模型类（JSON到JAXB模型的转换）添加自定义反序列化程序。

我想使用com。fasterxml。杰克逊。jaxrs。json。JacksonJaxbJsonProvider，用于其他数据模型的JSON序列化/反序列化。

JacksonJaxbJsonProvider的默认实现非常适合我的JAXB模型，将超类作为抽象类。但是，一旦我提供了自己的自定义ObjectMapper（如下所示），就不会使用默认的JacksonJaxbJsonProvider实现。i、 e自定义ObjectMapper没有正确转换为我的抽象类声明的JAXB注释和字段，因为它找不到在抽象类中声明的字段。

因此，我想根据所讨论的JAXB模型，同时使用自定义ObjectMapper和默认的JacksonJaxbJsonProvider实现。

40  package org.glassfish.jersey.examples.jackson;
41  
42  import javax.ws.rs.ext.ContextResolver;
43  import javax.ws.rs.ext.Provider;
44  
45  import com.fasterxml.jackson.databind.AnnotationIntrospector;
46  import com.fasterxml.jackson.databind.DeserializationFeature;
47  import com.fasterxml.jackson.databind.ObjectMapper;
48  import com.fasterxml.jackson.databind.SerializationFeature;
49  import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;
50  import com.fasterxml.jackson.databind.type.TypeFactory;
51  import com.fasterxml.jackson.module.jaxb.JaxbAnnotationIntrospector;
52  
53  /**
54   * TODO javadoc.
55   *
56   * @author Jakub Podlesak (jakub.podlesak at oracle.com)
57   */
58  @Provider
59  public class MyObjectMapperProvider implements ContextResolver<ObjectMapper> {
60  
61      final ObjectMapper defaultObjectMapper;
62      final ObjectMapper combinedObjectMapper;
63  
64      public MyObjectMapperProvider() {
65          defaultObjectMapper = createDefaultMapper();
66          combinedObjectMapper = createCombinedObjectMapper();
67      }
68  
69      @Override
70      public ObjectMapper getContext(final Class<?> type) {
71  
72          if (type == CombinedAnnotationBean.class) {
73              return combinedObjectMapper;
74          } else {
75              return defaultObjectMapper;
76          }
77      }
78  
79      private static ObjectMapper createCombinedObjectMapper() {
80          return new ObjectMapper()
81                  .configure(SerializationFeature.WRAP_ROOT_VALUE, true)
82                  .configure(DeserializationFeature.UNWRAP_ROOT_VALUE, true)
83                  .setAnnotationIntrospector(createJaxbJacksonAnnotationIntrospector());
84      }
85  
86      private static ObjectMapper createDefaultMapper() {
87          final ObjectMapper result = new ObjectMapper();
88          result.enable(SerializationFeature.INDENT_OUTPUT);
89  
90          return result;
91      }
92  
93      private static AnnotationIntrospector createJaxbJacksonAnnotationIntrospector() {
94  
95          final AnnotationIntrospector jaxbIntrospector = new JaxbAnnotationIntrospector(TypeFactory.defaultInstance());
96          final AnnotationIntrospector jacksonIntrospector = new JacksonAnnotationIntrospector();
97  
98          return AnnotationIntrospector.pair(jacksonIntrospector, jaxbIntrospector);
99      }
100 }

Answer 1

这个电话

.setAnnotationIntrospector(createJaxbJacksonAnnotationIntrospector());

是什么增加了JAXB对组合对象映射器的支持。因此，如果您希望JAXB支持defaultObjectMapper，只需添加相同的调用。

final ObjectMapper result = new ObjectMapper();
result.setAnnotationIntrospector(createJaxbJacksonAnnotationIntrospector());