Trouble using Jackson 2 with Spring 3.2

[smartnut007]

I am having trouble spring use the ObjectMapper in jackson 2.

How do i make Spring always use the jackson2 ObjectMapper by default.


In my pom I have

		
                <dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-databind</artifactId>
			<version>2.1.4</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>3.3.2.RELEASE</version>
		</dependency>

No other json library is included in my dependency tree.


My Controller looks like this
The two methods should be equivalent

1) "query" method takes the output object and explicitly writes it to string using the jackson2 ObjectMapper. This works fine.
2) "query2" returns the output object as it is and I want spring to pick up the jackson2 objectmapper in classpath. I expected this to work out of the box and the same as 1. But, I get the following errors.

	
@RequestMapping(value = "/query", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody String query(@RequestBody String request) throws JsonProcessingException {

	BasicDBObject output = new QueryProcessor(dl,request).processRequest();

	com.fasterxml.jackson.databind.ObjectMapper om = 
                              new com.fasterxml.jackson.databind.ObjectMapper();
	return om.writeValueAsString(output);
		
}
	
@RequestMapping(value = "/query2", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody BasicDBObject query2(@RequestBody String request) {
		
	BasicDBObject output = new QueryProcessor(dl,request).processRequest();
	return output;
		
}

While query method works fine, query2 throws the following errors.

11:35:09.814 [http-bio-8080-exec-1] DEBUG o.s.w.s.m.s.DefaultHandlerExceptionResolver - Resolving exception from handler [public com.mongodb.BasicDBObject origami.qengine.springy.Request.query2(java.util.Locale,org.springframework.ui.Model,java.lang.String)]: java.lang.RuntimeException: json can't serialize type : class origami.qengine.Channels$Channel
11:35:09.823 [http-bio-8080-exec-1] DEBUG o.s.web.servlet.DispatcherServlet - Could not complete request
java.lang.RuntimeException: json can't serialize type : class origami.qengine.Channels$Channel
	at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:77) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.JSONSerializers$MapSerializer.serialize(JSONSerializers.java:307) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:79) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.JSONSerializers$MapSerializer.serialize(JSONSerializers.java:307) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:79) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.JSON.serialize(JSON.java:56) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.util.JSON.serialize(JSON.java:41) ~[mongo-java-driver-2.10.1.jar:na]
	at com.mongodb.BasicDBObject.toString(BasicDBObject.java:83) ~[mongo-java-driver-2.10.1.jar:na]
	at java.lang.String.valueOf(String.java:2826) ~[na:1.6.0_43]
	at java.lang.StringBuilder.append(StringBuilder.java:115) ~[na:1.6.0_43]
	at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:150) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:90) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:189) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:69) ~[spring-web-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:122) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856) ~[spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936) [spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838) [spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:647) [servlet-api.jar:na]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812) [spring-webmvc-3.2.2.RELEASE.jar:3.2.2.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) [servlet-api.jar:na]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) [catalina.jar:7.0.37]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardContextValve.__invoke(StandardContextValve.java:123) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java) [catalina.jar:7.0.37]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardHostValve.__invoke(StandardHostValve.java:171) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java) [catalina.jar:7.0.37]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) [catalina.jar:7.0.37]
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936) [catalina.jar:7.0.37]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) [catalina.jar:7.0.37]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) [catalina.jar:7.0.37]
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004) [tomcat-coyote.jar:7.0.37]
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) [tomcat-coyote.jar:7.0.37]
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312) [tomcat-coyote.jar:7.0.37]
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895) [na:1.6.0_43]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918) [na:1.6.0_43]
	at java.lang.Thread.run(Thread.java:680) [na:1.6.0_43]

My servlet-context looks like this

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:beans="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

	<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->
	
	<!-- Enables the Spring MVC @Controller programming model -->
	<annotation-driven />
        <context:component-scan base-package="origami.qengine.springy" />

	<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
	<resources mapping="/resources/**" location="/resources/" />

	<!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
	<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<beans:property name="prefix" value="/WEB-INF/views/" />
		<beans:property name="suffix" value=".jsp" />
	</beans:bean>
	
	
	
	
	
</beans:beans>

[nickolayrusev]

Hello I'm using java config for my project. You can override configureMessageConverters and to set your custom object mapper . See code below:

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = {"org.mongo"}, excludeFilters = { @Filter(Configuration.class) })
public class WebConfig extends WebMvcConfigurerAdapter {

@Bean
public InternalResourceViewResolver resolver(){
InternalResourceViewResolver res = new InternalResourceViewResolver();
res.setSuffix(".jsp");
res.setPrefix("/WEB-INF/views/");
return res;

}
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/resources/").addResourceLocations("/resourses/**");
}
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new LoggerInterceptor()).addPathPatterns("/**");
super.addInterceptors(registry);
}
@Override
public void configureMessageConverters(List<HttpMessageConvert er<?>> converters) {
MappingJacksonHttpMessageConverter mappingJacksonHttpMessageConverter = new MappingJacksonHttpMessageConverter();
mappingJacksonHttpMessageConverter.setPrefixJson(f alse);
mappingJacksonHttpMessageConverter.setPrettyPrint( true);
mappingJacksonHttpMessageConverter.setObjectMapper (customObjectMapper);//here set your custom object mapper
converters.add(mappingJacksonHttpMessageConverter) ;
}

@Override
public void configureDefaultServletHandling(DefaultServletHand lerConfigurer configurer) {
configurer.enable();
}


}