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POJackson - deserialize into runtime specified class
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copied!<p>I'm writing a class that uses Jackson to serialize/deserialize objects. At compile time I don't know which is the type of the objects I will be serializing/deserializing.</p> <p>I read a couple of articles and questions about the usages of <code>TypeReference</code> and <code>TypeFactory</code>, however I'm still having some issues.</p> <p>My class looks like (removed some irrelevant code):</p> <pre><code>public class JsonSerializer<T> { private ObjectMapper objectMapper; private TypeReference typeReference; @PostConstruct public void init() { objectMapper = new ObjectMapper(); typeReference = new TypeReference<T>(){ }; } // ... public Object decode(CachedData cachedData) { try { return objectMapper.readValue(cachedData.getData(), typeReference); } // ... } } </code></pre> <p>And this is the snippet of code I'm using to test this:</p> <pre><code>public class SerializerTest { private JsonSerializer<Clazz> serializer; private ObjectMapper objectMapper = new ObjectMapper(); private static final String CHARSET = "UTF-8"; private Clazz data = generateData(); // creates a simple object @BeforeMethod public void beforeMethod() { serializer = new JsonSerializer<Clazz>(); serializer.init(); } // ... public void shouldDecodeDataCorrectly() throws Exception { CachedData cachedData = new CachedData(0, objectMapper.writeValueAsString(data).getBytes(CHARSET), CachedData.MAX_SIZE); Object object = serializer.decode(cachedData); assertEquals(data, object); } public static class Clazz { // POJO with getters and setters } } </code></pre> <p>As far as I could understand, using <code>typeReference</code> should be enough to let know the deserializer that the value read from the byte stream should be put in a <code>Clazz</code> object. However, the object returned by the <code>decode()</code> method is still a <code>Map</code>, which I understand is the default class for deserializing.</p> <p>I tried also changing the <code>decode()</code> method to return <code>return objectMapper.readValue(cachedData.getData(), objectMapper.getTypeFactory().constructType(typeReference))</code>, but I'm getting the same problem.</p> <p>I'm quite sure it's something regarding the way I pass the type into the serializer, but I haven't been able so far to fix it. Thanks.</p>

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