SPRINGMVC Unified Conversion Null value is an empty string method __null value Conversion

In the Java Web, if the value in the database is null without any conversion, uploading to the front-end page will appear null and affect the appearance. For example, this looks like this on the Zhaopin website:

In Springmvc, you can solve this problem by configuring <mvc:message-converters> in <mvc:annotation-driven>, and converting null values uniformly into empty strings. The following example of JSON interaction illustrates how to:

First step: Create a Objectmapper

Package com.xjj.anes.mvc.converter;

Import java.io.IOException;

Import Com.fasterxml.jackson.core.JsonGenerator;
Import com.fasterxml.jackson.core.JsonProcessingException;
Import Com.fasterxml.jackson.databind.JsonSerializer;
Import Com.fasterxml.jackson.databind.ObjectMapper;
Import Com.fasterxml.jackson.databind.SerializerProvider;

/**
 * @description: Convert null object to empty string
 */Public
class Jsonobjectmapper extends Objectmapper {
	private Static final Long serialversionuid = 1L;

	Public Jsonobjectmapper () {
		super ();
		Null-value processing is an empty string
		this.getserializerprovider (). Setnullvalueserializer (New jsonserializer<object> () {
			@ Override public
			void Serialize (Object value, Jsongenerator JG, Serializerprovider sp) throws IOException, jsonprocessingexception {
				jg.writestring ("");}}
		);
	}

Step Two:In the SPRINGMVC configuration file, inject the new objectmapper into the Mappingjackson2httpmessageconverter

	<!--register requestmappinghandlermapping and requestmappinghandleradapter two beans. -->
	<mvc:annotation-driven>
		<mvc:message-converters>
			<bean class= " Org.springframework.http.converter.json.MappingJackson2HttpMessageConverter ">
				<property name=" Objectmapper ">
					<bean class=" Com.xjj.anes.mvc.converter.JsonObjectMapper "></bean>
				</ property>
			</bean>
		</mvc:message-converters>
	</mvc:annotation-driven>

After restarting the server, you can see the effect.

Before conversion:

After conversion: