Exception in thread "main" java.lang.NoClassDefFoundError: com/fasterxml/jackson/annotation/JsonAutoDetect Error when trying to convert json to POJO

Question

I need to convert a json to a POJO, I have decided to go for the JACKSON library for that, I have added jackson-databind-2.2.3.jar and jackson-core-2.0.6.jar to my path and then have created the following classes:

1- Data-binding class :

package Distributed;

import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class DataBinding {

    public static void main(String[] args) throws JsonParseException, JsonMappingException, MalformedURLException, IOException {
        String url = "http://frstmwarwebsrv.orsyptst.com:9000/duobject?searchString=TSK(ZTA010OU05)(000)&filtercheck=nameSWF&p.index=0&p.size=8";
        ObjectMapper mapper = new ObjectMapper();
        mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
        DuObject duobject = mapper.readValue(new URL(url), DuObject.class);
        Dataset[] datasets = duobject.getDataset();
        for (Dataset dataset : datasets) {
            System.out.println(dataset.getName());
        }
    }
}

2- Dataset class :

package Distributed;

import java.util.HashMap;
import java.util.Map;

public class Dataset {

    private String id, name;
    private Map<String, Object> otherProperties = new HashMap<String, Object>();

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Object get(String name) {
        return otherProperties.get(name);
    }
}

3- DuObject class :

package Distributed;

public class DuObject {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Dataset[] getDataset() {
        return dataset;
    }

    public void setDataset(Dataset[] dataset) {
        this.dataset = dataset;
    }

    private Dataset[] dataset;
}

Here is my json object when launching teh URL used :

 {
"facets": {
"application": [
  {
    "name": "u_",
    "distribution": 2
  }
],
"node": [
  {
    "name": "frstlwardu03_05",
    "distribution": 2
  }
],
"area": [
  {
    "name": "x",
    "distribution": 2
  }
],
"company": [
  {
    "name": "war001",
    "distribution": 2
  }
]
 },
"duObjects": [
{
  "id": "TASK|TSK(ZTA010OU05)(000)|ZECPFICO00",
  "name": "TSK(ZTA010OU05)(000)",
  "mu": "ZECPFICO00",
  "label": "",
  "uprocHeader": "ZTA010OU05|000",
  "uprocHeaderLabel": "Uproc Tech Planif ne pas supprimer tous les jours f\u00c3\u00a9ri\u00c3\u00a9s",
  "uprocHeaderType": "CL_INT",
  "domain": "I",
  "domainLabel": "Internal Activities",
  "application": "U_",
  "applicationLabel": "DU",
  "highlightResult": {
    "name": "name",
    "word": "TSK"
  }
},
{
  "id": "TASK|TSK(ZTA010OU05)(000)|ZECPSDA000",
  "name": "TSK(ZTA010OU05)(000)",
  "mu": "ZECPSDA000",
  "label": "",
  "uprocHeader": "ZTA010OU05|000",
  "uprocHeaderLabel": "Uproc Tech Planif ne pas supprimer tous les jours f\u00c3\u00a9ri\u00c3\u00a9s",
  "uprocHeaderType": "CL_INT",
  "domain": "I",
  "domainLabel": "Internal Activities",
  "application": "U_",
  "applicationLabel": "DU",
  "highlightResult": {
    "name": "name",
    "word": "TSK"
  }
}
],
"totalCount": 2,
"pageSize": 10,
"pageCurrent": 1,
"pageNb": 1
}

What I want to do is to get DuObject.name and store it in a DataSet table; however when I run Databinding class I got the following error :

Exception in thread "main" java.lang.NoClassDefFoundError:     com/fasterxml/jackson/annotation/JsonAutoDetect
at com.fasterxml.jackson.databind.introspect.VisibilityChecker$Std.<clinit>  (VisibilityChecker.java:172)
at com.fasterxml.jackson.databind.ObjectMapper.<clinit>(ObjectMapper.java:193)
at Distributed.DataBinding.main(DataBinding.java:16)
  Caused by: java.lang.ClassNotFoundException:   com.fasterxml.jackson.annotation.JsonAutoDetect
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 3 more

I am a newbie to jackson livbrary and I have no clue why I am having this error.

Thanks in advance for your help.

After adding the annotation jar I am facing the following error :

Exception in thread "main" java.lang.NoSuchMethodError:      com.fasterxml.jackson.core.JsonFactory.createParser(Ljava/net/URL;)Lcom/fasterxml/jackson/core/JsonParser;
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2011)
at Distributed.DataBinding.main(DataBinding.java:18)

I have changed the three JARS to 2.1.2 version and the error I am getting now is :

Exception in thread "main" java.lang.NullPointerException
at Distributed.DataBinding.main(DataBinding.java:21)

In fact the Dataset table is returning null, any idea why the data set doese not contain the json name field?

Answer 1

You have to add one jar : jackson-annotations-2.1.2.jar

You can download it from here

Edit:

Also , since you have array in your json it needs to be traversed :

    ObjectMapper mapper = new ObjectMapper();
    mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
    JsonNode node = mapper.readTree(new URL(url));
    node = node.get("duObjects");

    TypeReference<List<Dataset>> typeRef = new TypeReference<List<Dataset>>() {
    };
    List<Dataset> list = mapper.readValue(node.traverse(), typeRef);
    for (int i = 0; i < list.size(); i++) {
        Dataset dataSet = list.get(i);
        System.out.println(dataSet.getName());
    }