Can not deserialize instance of java.lang.String out of START_OBJECT token

Question

I\'m running into an issue where my deployable jar hits an exception that doesn\'t happen when I run this locally in IntelliJ.

Exception:

Answer 1

You're mapping this JSON

{
    "id": 2,
    "socket": "0c317829-69bf-43d6-b598-7c0c550635bb",
    "type": "getDashboard",
    "data": {
        "workstationUuid": "ddec1caa-a97f-4922-833f-632da07ffc11"
    },
    "reply": true
}

that contains an element named data that has a JSON object as its value. You are trying to deserialize the element named workstationUuid from that JSON object into this setter.

@JsonProperty("workstationUuid")
public void setWorkstation(String workstationUUID) {

This won't work directly because Jackson sees a JSON_OBJECT, not a String.

Try creating a class Data

public class Data { // the name doesn't matter 
    @JsonProperty("workstationUuid")
    private String workstationUuid;
    // getter and setter
}

the switch up your method

@JsonProperty("data")
public void setWorkstation(Data data) {
    // use getter to retrieve it

Answer 2

If you do not want to define a separate class for nested json , Defining nested json object as JsonNode should work ,for example :

{"id":2,"socket":"0c317829-69bf-43d6-b598-7c0c550635bb","type":"getDashboard","data":{"workstationUuid":"ddec1caa-a97f-4922-833f-632da07ffc11"},"reply":true}

@JsonProperty("data")
    private JsonNode data;

Answer 3

Resolved the problem using Jackson library. Prints are called out of Main class and all POJO classes are created. Here is the code snippets.

MainClass.java

public class MainClass {
  public static void main(String[] args) throws JsonParseException, 
       JsonMappingException, IOException {

String jsonStr = "{\r\n" + "    \"id\": 2,\r\n" + " \"socket\": \"0c317829-69bf- 
             43d6-b598-7c0c550635bb\",\r\n"
            + " \"type\": \"getDashboard\",\r\n" + "    \"data\": {\r\n"
            + "     \"workstationUuid\": \"ddec1caa-a97f-4922-833f- 
            632da07ffc11\"\r\n" + " },\r\n"
            + " \"reply\": true\r\n" + "}";

    ObjectMapper mapper = new ObjectMapper();

    MyPojo details = mapper.readValue(jsonStr, MyPojo.class);

    System.out.println("Value for getFirstName is: " + details.getId());
    System.out.println("Value for getLastName  is: " + details.getSocket());
    System.out.println("Value for getChildren is: " + 
      details.getData().getWorkstationUuid());
    System.out.println("Value for getChildren is: " + details.getReply());

}

MyPojo.java

public class MyPojo {
    private String id;

    private Data data;

    private String reply;

    private String socket;

    private String type;

    public String getId() {
        return id;
    }

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

    public Data getData() {
        return data;
    }

    public void setData(Data data) {
        this.data = data;
    }

    public String getReply() {
        return reply;
    }

    public void setReply(String reply) {
        this.reply = reply;
    }

    public String getSocket() {
        return socket;
    }

    public void setSocket(String socket) {
        this.socket = socket;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    } 
}

Data.java

public class Data {
    private String workstationUuid;

    public String getWorkstationUuid() {
        return workstationUuid;
    }

    public void setWorkstationUuid(String workstationUuid) {
        this.workstationUuid = workstationUuid;
    }   
}

RESULTS:

Value for getFirstName is: 2
Value for getLastName  is: 0c317829-69bf-43d6-b598-7c0c550635bb
Value for getChildren is: ddec1caa-a97f-4922-833f-632da07ffc11
Value for getChildren is: true

Answer 4

This way I solved my problem. Hope it helps others. In my case I created a class, a field, their getter & setter and then provide the object instead of string.

Use this

public static class EncryptedData {
    private String encryptedData;

    public String getEncryptedData() {
        return encryptedData;
    }

    public void setEncryptedData(String encryptedData) {
        this.encryptedData = encryptedData;
    }
}

@PutMapping(value = MY_IP_ADDRESS)
public ResponseEntity<RestResponse> updateMyIpAddress(@RequestBody final EncryptedData encryptedData) {
    try {
        Path path = Paths.get(PUBLIC_KEY);
        byte[] bytes = Files.readAllBytes(path);
        PKCS8EncodedKeySpec ks = new PKCS8EncodedKeySpec(base64.decode(bytes));
        PrivateKey privateKey = KeyFactory.getInstance(CRYPTO_ALGO_RSA).generatePrivate(ks);

        Cipher cipher = Cipher.getInstance(CRYPTO_ALGO_RSA);
        cipher.init(Cipher.PRIVATE_KEY, privateKey);
        String decryptedData = new String(cipher.doFinal(encryptedData.getEncryptedData().getBytes()));
        String[] dataArray = decryptedData.split("|");


        Method updateIp = Class.forName("com.cuanet.client.helper").getMethod("methodName", String.class,String.class);
        updateIp.invoke(null, dataArray[0], dataArray[1]);

    } catch (Exception e) {
        LOG.error("Unable to update ip address for encrypted data: "+encryptedData, e);
    }

    return null;

Instead of this

@PutMapping(value = MY_IP_ADDRESS)
public ResponseEntity<RestResponse> updateMyIpAddress(@RequestBody final EncryptedData encryptedData) {
    try {
        Path path = Paths.get(PUBLIC_KEY);
        byte[] bytes = Files.readAllBytes(path);
        PKCS8EncodedKeySpec ks = new PKCS8EncodedKeySpec(base64.decode(bytes));
        PrivateKey privateKey = KeyFactory.getInstance(CRYPTO_ALGO_RSA).generatePrivate(ks);

        Cipher cipher = Cipher.getInstance(CRYPTO_ALGO_RSA);
        cipher.init(Cipher.PRIVATE_KEY, privateKey);
        String decryptedData = new String(cipher.doFinal(encryptedData.getBytes()));
        String[] dataArray = decryptedData.split("|");


        Method updateIp = Class.forName("com.cuanet.client.helper").getMethod("methodName", String.class,String.class);
        updateIp.invoke(null, dataArray[0], dataArray[1]);

    } catch (Exception e) {
        LOG.error("Unable to update ip address for encrypted data: "+encryptedData, e);
    }

    return null;
}

Answer 5

Data content is so variable, I think the best form is to define it as "ObjectNode" and next create his own class to parse:

Finally:

private ObjectNode data;