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PODon't return property when it's an empty list with jackson
 

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    <p>I have a class need to be dessrialized using jackson and the class has an collection property. The collection is empty, but not null. Question: How to desersialise the class <b>without</b> empty collection. Sample code below:</p> <pre><code>class Person { String name; List&lt;Event&gt; events; //....getter, setter } </code></pre> <p>if </p> <pre><code>person.list = new List&lt;Event&gt;(); persion.name = "hello"; </code></pre> <p>then excepted the json would be:</p> <pre><code>{name: "hello"} </code></pre> <p>not </p> <pre><code>{name: "hello", events:[]} </code></pre> <p>How to make it? Thank you~~</p> <p>================================================</p> <p>I have solved this by n1ckolas's advice. Thank you first. My jackson version is 2.1.1, and Spring-3.2.2 import better support for this verson of jackson. Also, this works for both <B> arrays and collection.</B> Below is my configuraion:</p> <pre><code>&lt;!-- Enables the Spring MVC @Controller programming model --&gt; &lt;mvc:annotation-driven&gt; &lt;mvc:message-converters&gt; &lt;bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"&gt; &lt;property name="objectMapper" ref="objectMapper"/&gt; &lt;/bean&gt; &lt;/mvc:message-converters&gt; &lt;/mvc:annotation-driven&gt; &lt;!--Json Mapper--&gt; &lt;bean name="objectMapper" class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean" autowire="no"&gt; &lt;property name="featuresToDisable"&gt; &lt;list&gt; &lt;!--not to return empty colletion--&gt; &lt;value type="com.fasterxml.jackson.databind.SerializationFeature"&gt;WRITE_EMPTY_JSON_ARRAYS&lt;/value&gt; &lt;/list&gt; &lt;/property&gt; &lt;/bean&gt; </code></pre>
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