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Junit test : Properties value are not resolved in Deserializer class

I'm writing some junit tests for my rest webservice. When I run my test, I got my response from the webservice. So I use objectMapper to map the json to my POJO class. However it fails on this line :
return objectMapper.readValue(json, clazz);
Error : com.fasterxml.jackson.databind.JsonMappingException: zoneId (through reference chain: com.customer.CustomerResponse["customerDetails"]->com.customer.CustomerDetails["licenseDate"])
This is because I'm using this annotation in my POJO class : #JsonDeserialize(using = CustomDateDeserializer.class) and in the Deserializer, I have a variable timezone , where the value is taken from properties file. It seems that the object Mapper is not able to resolve this properties in my Deserializer class :
#Value("${current.timezone}")
private String timezone;
Can you please help how to resolve this issue ? Thanks
#Transactional
#Rollback
class CustomerServiceIntegrationTest {
#Autowired
private DbUnitUtils dbUnitUtils;
protected MockMvc mvc;
#BeforeEach
void setup() throws Exception {
mvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
}
#BeforeEach
void setupData() throws Exception {
dbUnitUtils.initialiseDataSet(new File("src/test/resources/dbunit/test-dataset.xml"),
DatabaseOperation.CLEAN_INSERT);
}
#Test
void listCustomer_WhenIdExists_Then_ReturnCustomerInfo() throws Exception {
/*
* setup test-data
*/
Long idCustomer= 15L;
String uri = "/customer/" + 15L;
/*
* invoke endpoint being tested
*/
MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.get(uri).accept(MediaType.APPLICATION_JSON_VALUE))
.andReturn();
/*
* Verification
*/
int status = mvcResult.getResponse().getStatus();
assertEquals(200, status);
CustomerResponse customerResponse =
mapFromJson(mvcResult.getResponse().getContentAsString(), CustomerResponse.class);
assertEquals(idCustomer, customerResponse.getId());
}
protected <T> T mapFromJson(String json, Class<T> clazz)
throws JsonParseException, JsonMappingException, IOException {
ObjectMapper objectMapper = new ObjectMapper();
SimpleModule module =
new SimpleModule("CustomDateDeserializer", new Version(1, 0, 0, null, null, null));
module.addDeserializer(ZonedDateTime.class, new CustomDateDeserializer());
objectMapper.registerModule(module);
return objectMapper.readValue(json, clazz);
}
}
public class CustomerResponse{
String name;
String address;
String phoneNo;
CustomerDetails customerDetails;
//getter and setter
}
public class CustomerDetails {
#JsonDeserialize(using = CustomDateDeserializer.class)
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = Utils.FORMAT_DATE)
private ZonedDateTime licenseDate;
//getter and setters
}
public class CustomDateDeserializer extends StdDeserializer<ZonedDateTime> {
#Serial
private static final long serialVersionUID = 1L;
#Value("${current.timezone}")
private String timezone;
public CustomDateDeserializer () {
super((Class<?>) null);
}
protected CustomDateDeserializer (Class<?> vc) {
super(vc);
}
#Override
public ZonedDateTime deserialize(JsonParser p, DeserializationContext ctxt) throws
IOException {
String stringValue = p.getCodec().readValue(p, String.class);
if (StringUtils.isBlank(stringValue)) {
return null;
}
LocalDate localDate = LocalDate.parse(stringValue);
return localDate.atStartOfDay().atZone(ZoneId.of(timezone));
}
}
}

Deserialize multiple json fields into single java property

I want to convert a json into Java class by having custom deserializer.
I'm able to serialize ACC_NUM, NAME and any other fields from json but not sure what can be done to convert MOBILE_NUMBER_1,MOBILE_NUMBER_2 like fields into single JSONArray(See AccountInfo class). There can be many more fields like this and count also is not fixed. Example there can be ADDRESS_1, ADDRESS_2 till ADDRESS_20 and so on and all this fields should go in JSONArray of ADDRESS after deserilization.
I have a Map of Map which holds info like this:
{
"accountInfo": {
"ACC_NUM": "1234567890",
"NAME": "John Cena",
"MOBILE_NUMBER_1": "12376534",
"MOBILE_NUMBER_2": "12376534",
"MOBILE_NUMBER_3": "12376534",
"MOBILE_NUMBER_4": "12376534"
},
"someOther": {
//similer to above
}
}
This info I want to convert to the following class CommonInfo:
public class CommonInfo {
private AccountInfo accountInfo;
//other properties...
}
#JsonIgnoreProperties(ignoreUnknown = true)
public class AccountInfo {
#JsonProperty("ACC_NUM")
private FieldValue<BigInteger> accountNum;
#JsonProperty("NAME")
private FieldValue<String> name;
#JsonProperty("MOBILE_NUMBER")
private FieldValue<JSONArray> mobileNumber;
}
//FieldValue class
public interface FieldValue<T> {
T getInitialValue();
void setInitialValue(T initialValue);
T getValue();
void setValue(T value);
}
#JsonInclude(JsonInclude.Include.ALWAYS)
public class FieldValueImpl<T> implements FieldValue<T> {
protected T initialValue;
protected T value;
//getters, setters, cons..
}
My service code takes json/Map and tries to convert it to CommonInfo class
#Service
public class MyService {
private final ObjectMapper jsonMapper = new ObjectMapper();
#PostConstruct
protected void init() {
SimpleModule simpleModule = new SimpleModule();
simpleModule.addSerializer(FieldValue.class, new FieldValueSerializer());
simpleModule.addDeserializer(FieldValue.class, new FieldValueDeserializer());
jsonMapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
jsonMapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
jsonMapper.registerModule(simpleModule);
}
public CommonInfo setPojoResult(Map<String, LinkedHashMap<String, String>> contentAsMap) {
return jsonMapper.convertValue(contentAsMap, CommonInfo.class);
}
}
Serializer and Deserializer looks like this:
public class FieldValueDeserializer extends JsonDeserializer<FieldValue<?>> implements ContextualDeserializer {
private JavaType valueType;
public JsonDeserializer<?> createContextual(DeserializationContext ctxt, BeanProperty property)
throws JsonMappingException {
var deserializer = new FieldValueDeserializer();
if (property == null) {
deserializer.valueType = ctxt.getContextualType().containedType(0);
} else {
var wrapperType = property.getType();
var valueType = wrapperType.containedType(0);
deserializer.valueType = valueType;
}
return deserializer;
}
#Override
public FieldValue<?> deserialize(JsonParser parser, DeserializationContext context) throws IOException {
FieldValueDeserializer deserializer = new FieldValueDeserializer();
deserializer.getKnownPropertyNames();
FieldValue<?> fieldValueImpl = new FieldValueImpl<>();
if (valueType.toString().contains("java.time.LocalDate")) {
JsonNode node = parser.getCodec().readTree(parser);
FieldValue<LocalDate> f1 = new FieldValueImpl<>();
f1.setValue(DateUtils.convertJulianToLocalDate(node.textValue()));
return f1;
} else {
fieldValueImpl.setValue(context.readValue(parser, valueType));
}
return fieldValueImpl;
}
}
//--
public class FieldValueSerializer extends StdSerializer<FieldValue> {
public FieldValueSerializer() {
this(null);
}
public FieldValueSerializer(Class<FieldValue> vc) {
super(vc);
}
#Override
public void serialize(FieldValue value, JsonGenerator jgen, SerializerProvider provider) throws IOException {
jgen.writeString(String.valueOf(value.getCurValue()));
}
}

How to remove a field from POJO

public class user {
private String planId;
private String eid;
#JsonProperty(access = JsonProperty.Access.WRITE_ONLY)
private Collection<String> userIds;
}
I have a pojo like above
and the code which is use for creating the json request object is this :
public UserCollection getUserCollection(final user args) {
Map<String, String> headersMap = new HashMap<>();
ObjectMapper jacksonMapper = new ObjectMapper();
jacksonMapper.disable(MapperFeature.USE_ANNOTATIONS); // this line is creating the userIds field to reflect
//By any code we can remove the userId field from the args object
String responseBody = null;
String responseStatus = null;
String jsonRequestBody = jacksonMapper.writeValueAsString(args);
}
I just want to remove userIds from the args by not removing any of the above code.
Thanks in advance.

I don't know how you should solve this without removing the annotation processing code, you should maybe add a custom serializer. You can read further about the topic at here.
public class HelloWorld {
public static void main(String[] args) throws JsonProcessingException {
User myItem = new User("planId", "eId", List.of("1", "2"));
ObjectMapper mapper = new ObjectMapper();
SimpleModule module = new SimpleModule();
module.addSerializer(User.class, new UserSerializer());
mapper.registerModule(module);
String serialized = mapper.writeValueAsString(myItem);
}
#Data
#AllArgsConstructor
public static class User {
private String planId;
private String eId;
private Collection<String> userIds;
}
public static class UserSerializer extends StdSerializer<User> {
public UserSerializer() {
this(null);
}
public UserSerializer(Class<User> t) {
super(t);
}
#Override
public void serialize(User value, JsonGenerator gen, SerializerProvider provider) throws IOException{
gen.writeStartObject();
gen.writeStringField("planId", value.planId);
gen.writeStringField("eId", value.eId);
gen.writeEndObject();
}
}
}
If you had to use it without annotations, and cannot add a custom serializer you should map the User class into a more specific class without the field in question and then serialize that one.

Java Jackson: why do I get JsonMappingException although I used #JsonDeserialize

I need some help with Jackson library in Java. I have the following class:
#JsonIgnoreProperties(ignoreUnknown = true)
public class MarketHistoryData {
private String countryCode;
#JsonDeserialize(keyUsing = BpTimeDeserializer.class)
private Map<BpTime, Double> hourToExpectedEngagePaidListings;
#JsonDeserialize(keyUsing = BpTimeDeserializer.class)
private Map<BpTime, Double> hourMinuteToExpectedEngagePaidListings;
public MarketHistoryData() {}
...
// getters and setters
}
I understood that Jackson has difficulties with deserializing a map which its keys are an object. Therefore, I added the annotations:
#JsonDeserialize(keyUsing = BpTimeDeserializer.class)
The class BpTimeDeserializer is:
public class BpTimeDeserializer extends KeyDeserializer {
private ObjectMapper mapper = new ObjectMapper();
#Override
public BpTime deserializeKey(String key, DeserializationContext ctxt) throws IOException {
return mapper.readValue(key, BpTime.class);
}
}
Still, I get an error during the deserialization process:
*****.UncheckedExecutionException:
com.fasterxml.jackson.databind.JsonMappingException: Unrecognized
token 'com': was expecting (JSON String, Number, Array, Object or
token 'null', 'true' or 'false') at [Source:
(String)"****BpTime#5922062e[hour=1,minute=0]";
line: 1, column: 1] (through reference chain:
***PacerCycleOutput["campaignIdToFactorComputationData"]->java.util.LinkedHashMap["1011620661"]->****FactorComputationData["selectedMarketHistoryDataForCampaign"]->***MarketHistoryData["hourToExpectedEngagePaidListings"])
Do you know what I can do to overcome this error?

I finally found a way how to resolve this error.
#JsonIgnoreProperties(ignoreUnknown = true)
public class MarketHistoryData {
private String countryCode;
#JsonDeserialize(keyUsing = BpTimeDeserializer.class)
#JsonSerialize(keyUsing = BpTimeSerializer.class)
private Map<BpTime, Double> hourToExpectedEngagePaidListings;
#JsonDeserialize(keyUsing = BpTimeDeserializer.class)
#JsonSerialize(keyUsing = BpTimeSerializer.class)
private Map<BpTime, Double> hourMinuteToExpectedEngagePaidListings;
...
}
public class BpTimeDeserializer extends KeyDeserializer {
private ObjectMapper mapper = new ObjectMapper();
#Override
public BpTime deserializeKey(String key, DeserializationContext ctxt) throws IOException {
String[] keySplit = key.split(" ");
BpTime bpTime = new BpTime();
if (!keySplit[0].equals("-1")) {
bpTime.setHour(Integer.parseInt(keySplit[0]));
}
if (!keySplit[1].equals("-1")) {
bpTime.setMinute(Integer.parseInt(keySplit[1]));
}
return bpTime;
}
}
public class BpTimeSerializer extends StdSerializer<BpTime> {
public BpTimeSerializer() {
this(null);
}
public BpTimeSerializer(Class<BpTime> t) {
super(t);
}
#Override
public void serialize(BpTime value, JsonGenerator generator, SerializerProvider arg2) throws IOException {
generator.writeFieldName(String.format("%s %s", ofNullable(value.getHour()).orElse(-1),
ofNullable(value.getMinute()).orElse(-1)));
}
}

Serialize/Deserialize custom Map<Key, Object> in Jackson

I have a pretty simple Map I want to serialize and deserialize in Jackson, but I can't get it to work.
I have tried the following:
#JsonSerialize(keyUsing=TurnKeySerializer.class)
#JsonDeserialize(keyUsing = TurnKeyDeserializer.class)
Map<TurnKey, PlayerTurn> publicTurns = new TreeMap<>();
#JsonIgnoreProperties(ignoreUnknown = true)
#Data //Creates Getter/Setter etc
public class TurnKey implements Comparable<TurnKey> {
private final int turnNumber;
private final String username;
public TurnKey(int turnNumber, String username) {
this.turnNumber = turnNumber;
this.username = username;
}
#Override
public int compareTo(TurnKey o) {
int v = Integer.valueOf(turnNumber).compareTo(o.getTurnNumber());
if (v != 0) {
return v;
}
return username.compareTo(o.getUsername());
}
#Override
public String toString() {
return "{" +
"turnNumber:" + turnNumber +
", username:'" + username + "'" +
"}";
}
public class TurnKeySerializer extends JsonSerializer<TurnKey> {
#Override
public void serialize(TurnKey value, JsonGenerator gen, SerializerProvider serializers) throws IOException, JsonProcessingException {
if (null == value) {
throw new IOException("Could not serialize object to json, input object to serialize is null");
}
StringWriter writer = new StringWriter();
ObjectMapper mapper = new ObjectMapper();
mapper.writeValue(writer, value);
gen.writeFieldName(writer.toString());
}
}
public class TurnKeyDeserializer extends KeyDeserializer {
private static final ObjectMapper mapper = new ObjectMapper();
#Override
public TurnKey deserializeKey(String key, DeserializationContext ctxt) throws IOException, JsonProcessingException {
return mapper.readValue(key, TurnKey.class);
}
}
But I get an exception
com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.util.LinkedHashMap out of START_ARRAY token

You need to define/override the fromString() method in TurnKey. Jackson will use toString() to serialize and fromString() to deserialize. That's what "Can not find a (Map) Key deserializer" means in the error message Caused by: com.fasterxml.jackson.databind.JsonMappingException: Can not find a (Map) Key deserializer for type [simple type, class no.asgari.civilization.server.model.TurnKey] at com.fasterxml.jackson.databind.deser.DeserializerCache._handleUnknownKeyDeserializer(DeserializerCache.java:584).
A custom KeyDeserializer is not needed.