java Spring配置@ResponseBody JSON格式

Question

假设我在Spring3@控制器中有这个带注释的方法

@RequestMapping("")
public @ResponseBody MyObject index(@RequestBody OtherObject obj) {
    MyObject result = ...;
    return result;
}

但我需要配置输出json格式，就像我在做：

ObjectMapper om = new ObjectMapper();
om.configure(JsonGenerator.Feature.QUOTE_FIELD_NAMES, true);
om.getSerializationConfig()
        .setSerializationInclusion(JsonSerialize.Inclusion.NON_DEFAULT);
om.getSerializationConfig()
        .set(SerializationConfig.Feature.INDENT_OUTPUT, false);

有没有办法配置此行为

我发现了几个相关的问题，但我不确定如何使它们适应我的具体情况：

1. spring prefixjson with responsebody
2. Who sets response content-type in Spring MVC (@ResponseBody)

谢谢大家!

Answer 1

适用于Spring版本4.1.3+

我尝试了Jama的解决方案，但所有的响应都返回了“application/json”内容类型，包括主生成的HTML页面

重写configureMessageConverters(...)会阻止spring设置默认转换器。Spring 4.1.3允许修改已配置的转换器，方法是覆盖以下内容：

@Configuration
public class ConverterConfig extends WebMvcConfigurerAdapter {
    @Override
    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
        for (HttpMessageConverter<?> converter : converters) {
            if (converter instanceof AbstractJackson2HttpMessageConverter) {
                AbstractJackson2HttpMessageConverter c = (AbstractJackson2HttpMessageConverter) converter;
                ObjectMapper objectMapper = c.getObjectMapper();
                objectMapper.setSerializationInclusion(Include.NON_NULL);
            }
        }

        super.extendMessageConverters(converters);
    }
}

see org.springframework..WebMvcConfigurationSupport#getMessageConverters()

see org.springframework..WebMvcConfigurationSupport#addDefaultHttpMessageConverters(...)

Answer 2

春天。2，新的解决方案是由：http://static.springsource.org/spring/docs/3.2.0.BUILD-SNAPSHOT/api/org/springframework/http/converter/json/Jackson2ObjectMapperFactoryBean.html， 下面是我的例子：

 <mvc:annotation-driven>
   ​<mvc:message-converters>
     ​​<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
       ​​​<property name="objectMapper">
         ​​​​<bean
 class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean">
           ​​​​​<property name="featuresToEnable">
             ​​​​​​<array>
               ​​​​​​​<util:constant static-field="com.fasterxml.jackson.core.JsonParser.Feature.ALLOW_SINGLE_QUOTES" />
             ​​​​​​</array>
           ​​​​​</property>
         ​​​​</bean>
       ​​​</property>
     ​​</bean>
   ​</mvc:message-converters>
 </mvc:annotation-driven>

Answer 3

把pointed me移到正确的方向

这就是我最后做的，以防有人觉得有用

<bean
    class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
    <property name="messageConverters">
        <list>
            <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
                <property name="objectMapper" ref="jacksonObjectMapper" />
            </bean>
        </list>
    </property>
</bean>

<!-- jackson configuration : https://stackoverflow.com/questions/3661769 -->
<bean id="jacksonObjectMapper" class="org.codehaus.jackson.map.ObjectMapper" />
<bean id="jacksonSerializationConfig" class="org.codehaus.jackson.map.SerializationConfig"
    factory-bean="jacksonObjectMapper" factory-method="getSerializationConfig" />
<bean
    class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
    <property name="targetObject" ref="jacksonSerializationConfig" />
    <property name="targetMethod" value="setSerializationInclusion" />
    <property name="arguments">
        <list>
            <value type="org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion">NON_DEFAULT</value>
        </list>
    </property>
</bean>

我仍然需要弄清楚如何配置其他属性，例如：

om.configure(JsonGenerator.Feature.QUOTE_FIELD_NAMES, true);

Answer 4

我需要解决非常类似的问题，那就是将Jackson Mapper配置为“看在上帝的份上不要序列化空值！！！”

我不想留下花哨的mvc:annotation-driven标签，所以我找到了如何在不删除mvc:annotation-driven和添加不太花哨的ContentNegotingViewResolver的情况下配置Jackson的ObjectMapper

最美妙的是，你不必自己编写任何Java代码

这里是XML配置（不要与Jackson类的不同名称空间混淆，我只是使用了新的Jakson 2.x库……同样的配置也适用于Jackson 1.x库）：

<mvc:annotation-driven>
    <mvc:message-converters register-defaults="true">
        <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
            <property name="objectMapper">
                <bean class="com.fasterxml.jackson.databind.ObjectMapper">
                    <property name="serializationInclusion">
                        <value type="com.fasterxml.jackson.annotation.JsonInclude.Include">NON_NULL</value>
                    </property>
                </bean>
            </property>
        </bean>
    </mvc:message-converters>
</mvc:annotation-driven>

Answer 5

对于使用基于Java的Spring配置的用户：

@Configuration
@ComponentScan(basePackages = "com.domain.sample")
@EnableWebMvc
public class SpringConfig extends WebMvcConfigurerAdapter {
....

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        final MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        final ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        converter.setObjectMapper(objectMapper);
        converters.add(converter);
        super.configureMessageConverters(converters);
    }

....

}

我使用的是来自fasterxml的MappingJackson2HttpMessageConverter

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.3.1</version>
</dependency>

如果你想使用codehaus-jackson映射器，可以使用这个MappingJacksonHttpMessageConverter

 <dependency>
    <groupId>org.codehaus.jackson</groupId>
    <artifactId>jackson-mapper-asl</artifactId>
    <version>${codehaus.jackson.version}</version>
 </dependency>

Answer 6

我编写了自己的FactoryBean，它实例化了一个ObjectMapper（简化版）：

 public class ObjectMapperFactoryBean implements FactoryBean<ObjectMapper>{

        @Override
        public ObjectMapper getObject() throws Exception {
                ObjectMapper mapper = new ObjectMapper();
                mapper.getSerializationConfig().setSerializationInclusion(JsonSerialize.Inclusion.NON_NULL);
                return mapper;
        }

        @Override
        public Class<?> getObjectType() {
                return ObjectMapper.class;
        }

        @Override
        public boolean isSingleton() {
                return true;
        }

}

以及spring配置中的用法：

<bean
    class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
    <property name="messageConverters">
        <list>
            <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
                <property name="objectMapper" ref="jacksonObjectMapper" />
            </bean>
        </list>
    </property>
</bean>