We Keep Coding

How to prevent automatic update in Spring Data JPA?

In my Spring boot batch application, I am calling a JPA repository class from Tasklet.
The JPA call retrieves a particular value (Entity object) from DB. The problem is, If I update some value in the entity object, once the control goes out of Tasklet, it automatically updates to DB even though I am not calling any save operation. How to prevent this? Default JPA implementation is Hibernate.
Tasklet class
Employee employee = employeeRepository.fetchEmployee(employeeName);
List<Address> addressList = employee.getAddress();
addressList.forEach(e -> e.setStatus(Status.INVALID.toString()));
Repository
#Repository
public interface EmployeeRepository extends JpaRepository<Employee, Long> {
#Query("select em from Employee em where em.employeeName = :employeeName")
public Employee fetchEmployee(#Param("employeeName") Long employeeName);
}
Entity class
#Entity
#Table(name = "Employee")
public class Employee implements java.io.Serializable {
private static final long serialVersionUID = -3769636546619492649L;
private Long id;
private List<Address> address;
private String employeeName;
// Getters and setters
// #OneToMany mapping to Address
}
Even though I am not calling a .save() operation, it automatically updates Address table Status to "INVALID"

This happen because the entity is not in detached state. In EJB we can do this in the following way.
EJB solution
#Query(value = "select * from Employee WHERE EmployeeName = ?1", nativeQuery = true)
#TransactionAttribute(TransactionAttributeType.NOT_SUPPORTED)
public List<Employee> fetchEmployee(String employeeName);
This will make the transaction closed. Changes you make to entity will not get saved in DB
Spring JPA
After a bit of research i found JPA doesn't provide the detach functionality out of the box.
Refer : https://github.com/spring-projects/spring-data-jpa/issues/641
To make it work we can have a custom JPA repository which overrides detach method. An example is given in this link.
https://www.javaer101.com/en/article/1428895.html

Use Deep cloning to solve your issue.
First override the clone method inside your Address class like below.
Note : Please customize the implementation of clone() method by adding your class attributes.Since you didn't mention the structure of the class Address , I have implemented the solution with my own defined class attributes.
Address class
public class Address {
private String country;
private String city;
private String district;
private String addressValue;
public Address() {
super();
}
public Address(String country, String city, String district, String addressValue) {
super();
this.country = country;
this.city = city;
this.district = district;
this.addressValue = addressValue;
}
//Getters and Setters
#Override
protected Object clone() {
try {
return (Address) super.clone();
} catch (CloneNotSupportedException e) {
return new Address(this.getCountry(), this.getCity(), this.getDistrict(),this.getAddressValue());
}
}
}
Then re construct your class Tasket like below.
Tasket Class
Employee employee = employeeRepository.fetchEmployee(employeeName);
List<Address> addressList = employee.getAddress();
List<Address> clonedAddressList = new ArrayList<>();
addressList.forEach(address -> clonedAddressList.add((Address)address.clone()) );
clonedAddressList.forEach(address -> address.setStatus(Status.INVALID.toString()));

Javers #diffIgnore at class/property level not working with inheritance

We are building an application that needs to store differences made on existing opbjects.
Afterwards we will store these changes to the database. However for some reason the #diffIgnore option is not working on our User.class.
Every object extends our baseEntityCMS class, which has a property User. This is meant to store our update user information after the compare by JaVers is done. For some reason the user object is still compared even after setting #diffIgnore on property level and on class level.
Here is the code:
BaseEntityCMS.java
public class BaseEntityCMS extends BaseEntity {
private Boolean active;
private LocalDateTime inactiveDateTime;
private LocalDate creationDate;// in original application
private LocalDate importDate;
private LocalDate startDate;
private LocalDate endDate;
#Embedded
#DiffIgnore
private User modifierUser;
...
}
CodeList.java
public class CodeList extends BaseEntityCMS {
private String companyCode;
private Application sourceApplication;
private String name;
private String format;
private int length;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "codeList")
private List<Description> descriptionList;
#ManyToMany(cascade = CascadeType.ALL, mappedBy = "codeListList")
private List<Keyword> keywords;
private String domainOwner;
#OneToMany(cascade = CascadeType.REFRESH)
private List<Attribute> attributeList;
...
}
User.java
#Embeddable
#AllArgsConstructor
#Builder
#DiffIgnore
public class User {
private String userName;
}
TestCodeList.java
#Test
public void compareCodeListTest() {
Javers javers = JaversBuilder.javers().withListCompareAlgorithm(ListCompareAlgorithm.LEVENSHTEIN_DISTANCE)
.registerValueObject(BaseEntity.class).registerValue(Code.class).registerValue(Attribute.class)
.registerValue(AttributeValue.class).registerValue(MapCodeAttribute.class)
.registerValueObject(User.class).build();
CodeList codeListNew = createCodeListTest("ServiceTest");
CodeList codeListNew2 = createCodeListTest("ServiceTest");
Diff diff = javers.compare(codeListNew2, codeListNew);
assertNull(diff.getChanges());
}
So in the test class we create 2 CodeLists (codeListNew and codeListNew2) with a standard method.
Inside this method everything is created the same except we create a new User every time.
Because all properties of codeList (attribute, attributeValue, ...) extend the BaseEntityCMS class they all have a User property.
This is the output we get:
changes on xxx.CodeList/ :
- 'attributeList' collection changes :
1. 'Attribute(name=Address, format=freeformat, length=10, numberOfDecimals=2, description=description attribute, optional=true)' changed to 'Attribute(name=Address, format=freeformat, length=10, numberOfDecimals=2, description=description attribute, optional=true)'
0. 'Attribute(name=Number of employees, format=freeformat, length=10, numberOfDecimals=2, description=description attribute, optional=true)' changed to 'Attribute(name=Number of employees, format=freeformat, length=10, numberOfDecimals=2, description=description attribute, optional=true)'
- 'mapCodeAttributeMap' map changes :
'Code(super=BaseEntityCMS(super=BaseEntity(id=null), active=true, inactiveDateTime=null, creationDate=2020-03-23, importDate=2020-03-23, startDate=2020-03-23, endDate=2025-12-31, modifierUser=codems.agza.datalayer.model.User#57f83dc7), code=code1)' -> 'MapCodeAttribute(super=BaseEntity(id=null))' added
'Code(super=BaseEntityCMS(super=BaseEntity(id=null), active=true, inactiveDateTime=null, creationDate=2020-03-23, importDate=2020-03-23, startDate=2020-03-23, endDate=2025-12-31, modifierUser=codems.agza.datalayer.model.User#75937998), code=code1)' -> 'MapCodeAttribute(super=BaseEntity(id=null))' removed
We actually expect no difference since everything is the same but the User. This user is marked with #DiffIngore? How come we still have differences?
Forgot: we use
<dependency>
<groupId>org.javers</groupId>
<artifactId>javers-core</artifactId>
<version>5.8.11</version>
</dependency>

How to set Nested Object with Mongotemplate Spring

I'm still new in mongodb, If I have a class like below and I want to set a property Role which is Object Type Property, how can I achieve it ? please check the class below
#Document(collection="User")
public class UserBean {
#Id
private String id;
private String userName;
private String password;
private RoleBean role;
}
#Document(collection="Role")
public class RoleBean {
#Id
private String id;
private String roleID;
private String roleName;
}
I need to set the UserBean's role property. So what is the best way to achieve it? Thanks.

Spring Mongo Template not saving the list of custom objects to MongoDb please see if this quation is already answered, or answer satisfies your requirements.

Indexing composite object in spring mongodb

I have a composite object that I wish to store in mongodb (using spring annotations). The object is as follows:
#Document(collection="person")
class Person {
#Id
private String id;
private Address address;
private String name;
}
and the composite class Address:
#Document
class Address {
#Indexed
private Long countryId;
private String street;
#Indexed
private String city
}
I need both country and city to be indexed as part of the person collection. Alas, no index is created for them. Any ideas how to create the index?
I have tried the following which works but is not elegant:
#Document(collection="person")
#CompoundIndexes({
#CompoundIndex(name = "countryId", def = "{'address.countryId': 1}")
})
class Person {

You can set up multiple secondary indexes, if you wish. This would be a good place to start.

Only using #JsonIgnore during serialization, but not deserialization

I have a user object that is sent to and from the server. When I send out the user object, I don't want to send the hashed password to the client. So, I added #JsonIgnore on the password property, but this also blocks it from being deserialized into the password that makes it hard to sign up users when they don't have a password.
How can I only get #JsonIgnore to apply to serialization and not deserialization? I'm using Spring JSONView, so I don't have a ton of control over the ObjectMapper.
Things I've tried:
Add #JsonIgnore to the property
Add #JsonIgnore on the getter method only

Exactly how to do this depends on the version of Jackson that you're using. This changed around version 1.9, before that, you could do this by adding #JsonIgnore to the getter.
Which you've tried:
Add #JsonIgnore on the getter method only
Do this, and also add a specific #JsonProperty annotation for your JSON "password" field name to the setter method for the password on your object.
More recent versions of Jackson have added READ_ONLY and WRITE_ONLY annotation arguments for JsonProperty. So you could also do something like:
#JsonProperty(access = JsonProperty.Access.WRITE_ONLY)
private String password;
Docs can be found here.

In order to accomplish this, all that we need is two annotations:
#JsonIgnore
#JsonProperty
Use #JsonIgnore on the class member and its getter, and #JsonProperty on its setter. A sample illustration would help to do this:
class User {
// More fields here
#JsonIgnore
private String password;
#JsonIgnore
public String getPassword() {
return password;
}
#JsonProperty
public void setPassword(final String password) {
this.password = password;
}
}

Since version 2.6: a more intuitive way is to use the com.fasterxml.jackson.annotation.JsonProperty annotation on the field:
#JsonProperty(access = Access.WRITE_ONLY)
private String myField;
Even if a getter exists, the field value is excluded from serialization.
JavaDoc says:
/**
* Access setting that means that the property may only be written (set)
* for deserialization,
* but will not be read (get) on serialization, that is, the value of the property
* is not included in serialization.
*/
WRITE_ONLY
In case you need it the other way around, just use Access.READ_ONLY.

In my case, I have Jackson automatically (de)serializing objects that I return from a Spring MVC controller (I am using #RestController with Spring 4.1.6). I had to use com.fasterxml.jackson.annotation.JsonIgnore instead of org.codehaus.jackson.annotate.JsonIgnore, as otherwise, it simply did nothing.

Another easy way to handle this is to use the argument allowSetters=truein the annotation. This will allow the password to be deserialized into your dto but it will not serialize it into a response body that uses contains object.
example:
#JsonIgnoreProperties(allowSetters = true, value = {"bar"})
class Pojo{
String foo;
String bar;
}
Both foo and bar are populated in the object, but only foo is written into a response body.

"user": {
"firstName": "Musa",
"lastName": "Aliyev",
"email": "klaudi2012#gmail.com",
"passwordIn": "98989898", (or encoded version in front if we not using https)
"country": "Azeribaijan",
"phone": "+994707702747"
}
#CrossOrigin(methods=RequestMethod.POST)
#RequestMapping("/public/register")
public #ResponseBody MsgKit registerNewUsert(#RequestBody User u){
root.registerUser(u);
return new MsgKit("registered");
}
#Service
#Transactional
public class RootBsn {
#Autowired UserRepository userRepo;
public void registerUser(User u) throws Exception{
u.setPassword(u.getPasswordIn());
//Generate some salt and setPassword (encoded - salt+password)
User u=userRepo.save(u);
System.out.println("Registration information saved");
}
}
#Entity
#JsonIgnoreProperties({"recordDate","modificationDate","status","createdBy","modifiedBy","salt","password"})
public class User implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String country;
#Column(name="CREATED_BY")
private String createdBy;
private String email;
#Column(name="FIRST_NAME")
private String firstName;
#Column(name="LAST_LOGIN_DATE")
private Timestamp lastLoginDate;
#Column(name="LAST_NAME")
private String lastName;
#Column(name="MODIFICATION_DATE")
private Timestamp modificationDate;
#Column(name="MODIFIED_BY")
private String modifiedBy;
private String password;
#Transient
private String passwordIn;
private String phone;
#Column(name="RECORD_DATE")
private Timestamp recordDate;
private String salt;
private String status;
#Column(name="USER_STATUS")
private String userStatus;
public User() {
}
// getters and setters
}

You can use #JsonIgnoreProperties at class level and put variables you want to igonre in json in "value" parameter.Worked for me fine.
#JsonIgnoreProperties(value = { "myVariable1","myVariable2" })
public class MyClass {
private int myVariable1;,
private int myVariable2;
}

You can also do like:
#JsonIgnore
#JsonProperty(access = Access.WRITE_ONLY)
private String password;
It's worked for me

I was looking for something similar. I still wanted my property serialized but wanted to alter the value using a different getter. In the below example, I'm deserializing the real password but serializing to a masked password. Here's how to do it:
public class User() {
private static final String PASSWORD_MASK = "*********";
#JsonIgnore
private String password;
#JsonProperty(access = JsonProperty.Access.WRITE_ONLY)
public String setPassword(String password) {
if (!password.equals(PASSWORD_MASK) {
this.password = password;
}
}
public String getPassword() {
return password;
}
#JsonProperty("password")
public String getPasswordMasked() {
return PASSWORD_MASK;
}
}

The ideal solution would be to use DTO (data transfer object)