I need to deserialize the Json to Java Objects in Junit. I have Json file like
{
"studentId":57,
"JoinedDate":"31-12-2019",
"DOB":"08-06-1998"
}
I have class for the same to map
public class Student{
private long studentId ;
private LocalDate JoinedDate;
private LocalDate DOB ;
public long getStudentId() {
return studentId;
}
public void setStudentId(long studentId) {
this.studentId = studentId;
}
public LocalDate getJoinedDate() {
return JoinedDate;
}
public void setJoinedDate(LocalDate joinedDate) {
JoinedDate = joinedDate;
}
public LocalDate getDOB() {
return DOB;
}
public void setDOB(LocalDate dOB) {
DOB = dOB;
}
I need to write centralized builder for Unit testing project similar like this
builder.deserializers(new LocalDateDeserializer(DateTimeFormatter.ofPattern(dateFormat)));
builder.serializers(new LocalDateSerializer(DateTimeFormatter.ofPattern(dateFormat)));
Main Class
#RunWith(SpringRunner.class)
#SpringBootTest(classes = Main.class)
#WebAppConfiguration
public class Main{
#Test
public void contextLoads() {
assertTrue(true);
}
}
Unit testing Project looks like
#RunWith(SpringRunner.class)
#SpringBootTest(classes = Main.class)
#WebAppConfiguration
public class StudentTest{
private ObjectMapper jsonObjectMapper;
#Before
public void setUp() throws IOException {
jsonObjectMapper = new ObjectMapper();
studentJson = IOUtils.toString(getClass().getResourceAsStream(CommonTestConstants.StudentPath+ "/Student.json"));
}
I'm getting a error while mapping the objects -
com.fasterxml.jackson.databind.exc.InvalidFormatException: Cannot deserialize value of type java.time.LocalDate from String "31-12-2019": Failed to deserialize java.time.LocalDate:
Another Error - Sometimes.
com.fasterxml.jackson.databind.JsonMappingException: Text '31-12-2019'
could not be parsed at index 0
I assume LocalDate format mismatch is the issue. Any suggestion to make it centralized way instead of specifying the format above the fields. Any one please advise?
Reference - Spring Boot JacksonTester custom serializer not registered
You just need to specify the date format by default jackson allows format of yyyy-MM-dd
public class Student{
private long studentId ;
#JsonProperty("JoinedDate") #JsonFormat(pattern = "dd/MM/yyyy")
private LocalDate JoinedDate;
#JsonProperty("DOB") #JsonFormat(pattern = "dd/MM/yyyy")
private LocalDate DOB ;
public long getStudentId() {
return studentId;
}
public void setStudentId(long studentId) {
this.studentId = studentId;
}
public LocalDate getJoinedDate() {
return JoinedDate;
}
public void setJoinedDate(LocalDate joinedDate) {
this.JoinedDate = joinedDate;
}
public LocalDate getDOB() {
return DOB;
}
public void setDOB(LocalDate dOB) {
this.DOB = dOB;
}
I hope it helps you
Springboot 1.4.x or above has this interface Jackson2ObjectMapperBuilderCustomizer which allows you to initialize objectMapper.
What we need to do, is override customize method and register deserializers and
serializers.
#SpringBootApplication
public class TestApplication implements Jackson2ObjectMapperBuilderCustomizer {
#Override
public void customize(Jackson2ObjectMapperBuilder jackson2ObjectMapperBuilder) {
// pattern could be anything whatever is required
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy/dd/MM");
LocalDateSerializer localDateDeserializer = new LocalDateSerializer(formatter);
jackson2ObjectMapperBuilder
.failOnEmptyBeans(false)
.deserializersByType(new HashMap<Class<?>, JsonDeserializer<?>>(){{
put(LocalTime.class, localTimeSerializer);
}});
}
}
We can also add seriliazers similar way.
jackson2ObjectMapperBuilder
.failOnEmptyBeans(false)
.serializersByType(new HashMap<Class<?>, JsonSerializer<?>>(){{
put(LocalTime.class, localTimeSerializer);
}});
you can check more details here. Spring Jackson builder
Related
Vaadin + Spring + MySQL
I try to update my object's LocalDate attribute via query with java.time.LocalDate attribute converted to java.sql.Date
Entity:
import java.time.LocalDate;
#Entity
#Table(name = "ENTERPRISES")
public class Enterprise {
int enterpriseId;
String name;
LocalDate expiryDate;
public Enterprise(String name) {
this.name = name;
}
public Enterprise() {
}
#Id
#GeneratedValue
#NotNull
#Column(unique = true)
public int getEnterpriseId() {
return enterpriseId;
}
#Column
public String getName() { return name; }
#Column
public LocalDate getExpiryDate() {
return expiryDate;
}
public void setEnterpriseId(int enterpriseId) {
this.enterpriseId = enterpriseId;
}
public void setName(String name) { this.name = name; }
public void setExpiryDate(LocalDate expiryDate) {
this.expiryDate = expiryDate;
}
}
Service layer:
import java.sql.Date;
import java.time.LocalDate;
#Service
public class EnterpriseService {
private static EnterpriseService enterpriseService;
private EnterpriseDao enterpriseDao;
public EnterpriseService(EnterpriseDao enterpriseDao) {
this.enterpriseDao = enterpriseDao;
}
public void updateExpiryDate(int enterpriseId, LocalDate newExpiryDate) {
Date expiryDate = Date.valueOf(newExpiryDate);
enterpriseDao.updateExpiryDate(enterpriseId, expiryDate);
}
}
repository layer:
import java.sql.Date;
import java.time.LocalDate;
public interface EnterpriseDao extends CrudRepository<Enterprise, Integer> {
#Modifying
#Query("update Enterprise e set e.expiryDate = :expiryDate where e.enterpriseId = :enterpriseId")
void updateExpiryDate(#Param(value = "enterpriseId") int enterpriseId, #Param(value = "expiryDate") Date expiryDate);
}
When I try to call method in my application:
enterpriseService.updateExpiryDate(enterpriseX.getEnterpriseId(), LocalDate.of(2022, 12, 12));
I get exception:
Caused by: org.springframework.dao.InvalidDataAccessApiUsageException: Parameter value [2022-12-12] did not match expected type [java.time.LocalDate (n/a)]; nested exception is java.lang.IllegalArgumentException: Parameter value [2022-12-12] did not match expected type [java.time.LocalDate (n/a)]
I tried changing date types in DAO method to LocalDate but with no success
Since the attribute expiryDate on your Enterprise entity is a java.time.LocalDate, the parameter :expiryDate in the query must be a java.time.LocalDate. Therefore, you should change the parameter expiryDate of updateExpiryDate().
I'm facing an error while deserialize the string to object.
org.opentest4j.MultipleFailuresError: Multiple Failures (2 failures)
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot
construct instance of java.time.LocalDate (no Creators, like default
construct, exist): no String-argument constructor/factory method to
deserialize from String value ('2020-05-20') at [Source: (String)
JSON
{
"studentId":57,
"JoinedDate":"31-12-2019",
"DOB":"08-06-1998"
}
Model
public class Student{
private long studentId ;
private LocalDate JoinedDate;
private LocalDate DOB ;
public long getStudentId() {
return studentId;
}
public void setStudentId(long studentId) {
this.studentId = studentId;
}
public LocalDate getJoinedDate() {
return JoinedDate;
}
public void setJoinedDate(LocalDate joinedDate) {
JoinedDate = joinedDate;
}
public LocalDate getDOB() {
return DOB;
}
public void setDOB(LocalDate dOB) {
DOB = dOB;
}
Unit Test Class
#RunWith(SpringRunner.class)
#SpringBootTest(classes = Main.class)
#WebAppConfiguration
public class StudentTest{
private Student student;
private ObjectMapper jsonObjectMapper;
#Before
public void setUp() throws IOException {
jsonObjectMapper = new ObjectMapper();
jsonObjectMapper.setDateFormat(new SimpleDateFormat("dd-MM-yyyy"));
studentJson = IOUtils.toString(getClass().getResourceAsStream(CommonTestConstants.StudentPath+ "/Student.json"));
student = jsonObjectMapper.readValue(studentJson , Student.class);
}
Any one please advise
Reference
Cannot construct instance of `java.time.ZonedDateTime` (no Creators, like default construct, exist)
Unable to Deserialize - Jackson LocalDate/Time - JUnit
Include jackson jsr310 module.
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jsr310</artifactId>
<version>2.11.0</version>
</dependency>
Register JavaTimeModule
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.registerModule(new JavaTimeModule());
Mark the LocalDate type fields in your java class with following annotations.
#JsonFormat(pattern = "dd-MM-yyyy")
#JsonDeserialize(using = LocalDateDeserializer.class)
Complete code would be:
Main class or junit :
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.registerModule(new JavaTimeModule());
Student student = objectMapper.readValue(YOUR_JSON_STRING, Student.class);
System.out.println(student);
}
Student:
public class Student {
private long studentId;
#JsonProperty("JoinedDate")
#JsonFormat(pattern = "dd-MM-yyyy")
#JsonDeserialize(using = LocalDateDeserializer.class)
private LocalDate JoinedDate;
#JsonFormat(pattern = "dd-MM-yyyy")
#JsonDeserialize(using = LocalDateDeserializer.class)
private LocalDate DOB;
// getters and setters and ToString
}
I am returning a JSON as a response from the controller. I want to format the date fields in this response.
Controller-
#RequestMapping(value = "/call", method = RequestMethod.GET)
public SampleDTO get()
{
......
return sampleDTO;
}
SampleDTO-
{
"date" : "2020-03-10T08:57:58+0000",
"text" : "abc"
}
I want to format the date field to dd-MM-yyyy
To do this I add the #JsonFormat annotation to the bean class of SampleDTO.
SampleDTO.java -
import java.util.Date;
public class SampleDTO
{
#JsonFormat(pattern = "dd-MM-yyyy")
private Date date;
private String text;
#JsonFormat(pattern = "dd-MM-yyyy")
public void setDate(final Date date)
{
this.date = date;
}
#JsonFormat(pattern = "dd-MM-yyyy")
public Date getDate()
{
return date;
}
public void setText(final String text)
{
this.text = text;
}
public String getText()
{
return text;
}
}
Still, I am getting this format in the response on my browser.
"date" : "2020-03-10T08:57:58+0000"
EDIT 1:
Instead of returning the sampleDTO, converting it to String directly in the code works perfectly fine.
This works like a charm:
SampleDTO sampleDTO = new SampleDTO();
sampleDTO.setCreated(new Date());
ObjectMapper om = new ObjectMapper();
return om.writeValueAsString(sampleDTO);
Please, check that your Date is from java.util and not from java.sql package. Plus try the following:
#JsonSerialize(as = Date.class)
#JsonFormat(shape=JsonFormat.Shape.STRING, pattern="dd-MM-yyyy")
Could you try this on the field level and remove from getDate() method in your DTO.
Something like this,
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd-MM-yyyy")
private Date date;
This should work with your current version of jackson-databind:2.9.8.jar.
Here is the small example for you:
public class ExampleMain {
public static void main(String[] args) throws IOException {
Employee employee = new Employee();
employee.setDateOfBirth(Date.from(ZonedDateTime.now().minusYears(30).toInstant()));
System.out.println("-- before serialization --");
System.out.println(employee);
System.out.println("-- after serialization --");
ObjectMapper om = new ObjectMapper();
String jsonString = om.writeValueAsString(employee);
System.out.println(jsonString);
System.out.println("-- after deserialization --");
System.out.println(om.readValue(jsonString, Employee.class));
}
}
public class Employee {
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd-MM-yyyy")
private Date dateOfBirth;
public Date getDateOfBirth() {
return dateOfBirth;
}
public void setDateOfBirth(Date dateOfBirth) {
this.dateOfBirth = dateOfBirth;
}
#Override
public String toString() {
return "Employee{" +
", dateOfBirth=" + dateOfBirth +
'}';
}
}
There are three levels of how you can solve this date format issue with Spring.
1) Using #JsonFormat on your date fields
In this case, you need to use the same annotation in front of all your private date members.
public class MyBean{
#JsonFormat(pattern="yyyy-MM-dd")
private Date birthday;
#JsonFormat(pattern="yyyy-MM-dd")
private LocalDate birthday;
// getters and setters here
}
2) Setting the Default format
If you want to configure the default date format for all dates in your application, add the following line to the application.properties or application.yml config file:
spring.jackson.date-format=yyyy-MM-dd
Unfortunately, this solution doesn't work with the Java 8 date types, like LocalDate and LocalDateTime.
3) Customizing your Jackson ObjectMapper
This solution works like a charm with Java 8 date types as well.
#Configuration
public class ContactAppConfig {
private static final String DATE_FORMAT = "yyyy-MM-dd";
private static final String DATE_TIME_FORMAT = "yyyy-MM-dd HH:mm:ss";
#Bean
public Jackson2ObjectMapperBuilderCustomizer jsonCustomizer() {
return builder -> {
builder.simpleDateFormat(DATE_TIME_FORMAT);
builder.serializers(new LocalDateSerializer(DateTimeFormatter.ofPattern(DATE_FORMAT)));
builder.serializers(new LocalDateTimeSerializer(DateTimeFormatter.ofPattern(DATE_TIME_FORMAT)));
};
}
}
I suggest you use the 3rd option.
you can use jstl format to format the date :)
<%# taglib prefix = "fmt" uri = "http://java.sun.com/jsp/jstl/fmt" %>
<fmt:formatDate pattern = "yyyy-MM-dd" value = "${date}" />
I'm switching from MongoDB to DynamoDB on a project. Now I'm trying to store this Post object in the db. I'm using the DynamoDBTypeConverter to convert the ZonedDateTime to a String, as DynamoDB doesn't support ZonedDateTime.
That works fine, but when I'm adding a ZonedDateTime field in the Comment object and try to convert it too it doesn't work. I've tried adding a converter to the Comment class, and tried using the converter in the Post class for Comment, but nothing seems to work. Is there a way to convert a field in a nested object for DynamoDB?
com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: Cannot marshall type class java.time.ZonedDateTime without a custom marshaler or #DynamoDBDocument annotation.
#DynamoDBTable(tableName = "Post")
public class Post {
#DynamoDBHashKey
private String postNumber;
private ZonedDateTime date;
private List<Comment> comments;
#DynamoDBTypeConverted(converter = ZonedDateTimeConverter.class)
#DynamoDBAttribute
public ZonedDateTime getDate() {
return date;
}
#DynamoDBAttribute(attributeName = "comments")
public List<Comment> getComments() {
return comments;
}
static public class ZonedDateTimeConverter implements DynamoDBTypeConverter<String, ZonedDateTime> {
#Override
public String convert(final ZonedDateTime time) {
return time.toString();
}
#Override
public ZonedDateTime unconvert(final String stringValue) {
return ZonedDateTime.parse(stringValue);
}
}
#DynamoDBDocument
public class Comment {
private String commentNumber;
#NotNull
private User user;
private ZonedDateTime date;
#DynamoDBTypeConverted(converter = ZonedDateTimeConverter.class)
#DynamoDBAttribute
public ZonedDateTime getDate(){
return this.date;
}
static public class ZonedDateTimeConverter implements DynamoDBTypeConverter<String, ZonedDateTime> {
#Override
public String convert(final ZonedDateTime time) {
return time.toString();
}
#Override
public ZonedDateTime unconvert(final String stringValue) {
return ZonedDateTime.parse(stringValue);
}
}
Is there a better way of writing a Java validator which ensures that a start date is before an end date than writing a class level ConstraintValidator in the following manner:
// VALIDATOR IMPLEMENTATION
public class StartBeforeEndDateValidator implements ConstraintValidator<StartBeforeEndDateValid, Object> {
// cannot use LocalDate here...
private String start;
private String end;
#Override
public void initialize(final StartBeforeEndDateValid annotation) {
start = annotation.start();
end = annotation.end();
}
#Override
public boolean isValid(final Object bean, final ConstraintValidatorContext context) {
try {
final String startDateStr = BeanUtils.getProperty(bean, start);
final String endDateStr = BeanUtils.getProperty(bean, end);
final LocalDate startDate = new LocalDate(startDateStr);
final LocalDate endDate = new LocalDate(endDateStr);
return !startDate.isAfter(endDate);
} catch (final Exception e) {
return false;
}
}
}
// USAGE
#StartBeforeEndDateValid(start = "startDate", end = "endDate")
#Entity
public class MyBean {
#NotNull
#Type(type = "org.jadira.usertype.dateandtime.joda.PersistentLocalDate")
private LocalDate startDate;
#Type(type = "org.jadira.usertype.dateandtime.joda.PersistentLocalDate")
private LocalDate endDate;
...
}
I don't really like the fact that I have to use reflection to extract the 2 date objects from the bean. Unfortunately afaik the validation spec does not specify a way to set only the values you want to validate from the bean.
One way would be to add an interface to MyBean
public interface StartEndDateable {
public LocalDate getStartDate();
public LocalDate getEndDate();
}
public class MyBean implements StartEndDatable {
...
Then you can set the generic type on ConstraintValidator to the new interface instead of Object.
public class StartBeforeEndDateValidator implements ConstraintValidator<StartBeforeEndDateValid, StartEndDatable> {
#Override
public void initialize(StartBeforeEndDateValid annotation) {
}
#Override
public boolean isValid(StartEndDatable bean, ConstraintValidatorContext context) {
final LocalDate startDate = bean.getStartDate();
final LocalDate endDate = bean.getEndDate();
return !startDate.isAfter(endDate);
}
}
Obviously any class you then want to validate with the start and end date will have to implement the StartEndDateable (Not the best name, I know, but I'm sure you can think of something better) and define the getStartDate and getEndDate methods.