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POJSON: JsonMappingException while try to deserialize object with null values
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  1. POJSON: JsonMappingException while try to deserialize object with null values
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    copied!<p>I try to deserialize object that contains null-properties and have the <code>JsonMappingException</code>.</p> <p><strong>What I do:</strong></p> <pre><code>String actual = "{\"@class\" : \"PersonResponse\"," + " \"id\" : \"PersonResponse\"," + " \"result\" : \"Ok\"," + " \"message\" : \"Send new person object to the client\"," + " \"person\" : {" + " \"id\" : 51," + " \"firstName\" : null}}"; ObjectMapper mapper = new ObjectMapper(); mapper.readValue(new StringReader(json), PersonResponse.class); //EXCEPTION! </code></pre> <p><strong>BUT</strong>: if to throw away <code>"firstName = null"</code> property - all works fine! I mean pass the next string:</p> <pre><code>String test = "{\"@class\" : \"PersonResponse\"," + " \"id\" : \"PersonResponse\"," + " \"result\" : \"Ok\"," + " \"message\" : \"Send new person object to the client\"," + " \"person\" : {" + " \"id\" : 51}}"; ObjectMapper mapper = new ObjectMapper(); mapper.readValue(new StringReader(json), PersonResponse.class); //ALL WORKS FINE! </code></pre> <p><strong>Question</strong>: How to avoid this exception or to pledge Jackson ignore null-values during serialization?</p> <p><strong>Throws:</strong></p> <p><strong><em>Message:</em></strong> </p> <pre><code>com.fasterxml.jackson.databind.MessageJsonException: com.fasterxml.jackson.databind.JsonMappingException: N/A (through reference chain: person.Create["person"]-&gt;Person["firstName"]) </code></pre> <p><strong><em>cause:</em></strong> </p> <pre><code>com.fasterxml.jackson.databind.MessageJsonException: com.fasterxml.jackson.databind.JsonMappingException: N/A (through reference chain: prson.Create["person"]-&gt;Person["firstName"]) </code></pre> <p><strong><em>cause:</em></strong> <code>java.lang.NullPointerException</code></p>
 

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