We Keep Coding

How to set the Boolean value as false in Java Spring boot

I am practicing Java and Spring Boot.
Actually my idea is if we send json delete request means it should change details in the database as inactive instead of deleting that data.
for Example if I want to delete the student record. Base on student ID as 1 means it should change the student status as inactive instead of deleting that record.
In spring boot controller I have a delete method.
Codes are below for your understanding:
Controller:
#DeleteMapping("v1/student/delete/{id}")
public ResponseEntity<String> deleteStudentDetails(#PathVariable("id") Integer getId) {
studentService.deleteStudentdetails(getId);
return new ResponseEntity<>("STUDENT RECORD HAS BEEN DELETED !!!", HttpStatus.OK);
}
studentService = is a service class which sending the information from controller to service.
deleteStudentdetails = is a method in service class.
Service class method
public void deleteStudentdetails(Integer getId) {
Optional<StudentDetails> studentIdDetails = studentRepo.findById(getId); // getting info from DB
StudentDetails studentIsdetail = studentIdDetails.get();
if (studentIsdetail.getActive() == false) {
throw new RuntimeException("Student is Already inActive!!");
}
studentIsdetail.setActive(false); // Here I want to change the Active Status from True to false
}
Here I am changing the values in the Database by retrieving the student ID which is already existing in the DB.
STUDENT_ID ACTIVE BOARD_ID
60 TRUE STATEBOARD
116 TRUE STATEBOARD //here want to change the status as False
120 FALSE STATEBOARD

You never save studentIsdetail into the database after modifying.
So just add studentRepo.save(studentIsdetail); after calling studentIsdetail.setActive(false); and it should work:
public void deleteStudentdetails(Integer getId) {
Optional<StudentDetails> studentIdDetails = studentRepo.findById(getId); // getting info from DB
StudentDetails studentIsdetail = studentIdDetails.get();
if (!studentIsdetail.getActive()) {
throw new RuntimeException("Student is Already inActive!!");
}
studentIsdetail.setActive(false);
studentRepo.save(studentIsdetail);
}
And I recommend that you check if you get a result to avoid exceptions:
public void deleteStudentdetails(Integer getId) {
Optional<StudentDetails> studentIdDetails = studentRepo.findById(getId); // getting info from DB
if (studentIsdetail.isEmpty()) {
// handle e.g. throw exception or just return (with return:)
return;
}
StudentDetails studentIsdetail = studentIdDetails.get();
if (!studentIsdetail.getActive()) {
throw new RuntimeException("Student is Already inActive!!");
}
studentIsdetail.setActive(false);
studentRepo.save(studentIsdetail);
}
For this you can also use Optional#ifPresent:
public void deleteStudentdetails(Integer getId) {
Optional<StudentDetails> studentIdDetails = studentRepo.findById(getId); // getting info from DB
studentIdDetails.ifPresent((studentIsdetail) -> {
if (!studentIsdetail.getActive()) {
throw new RuntimeException("Student is Already inActive!!");
}
studentIsdetail.setActive(false);
studentRepo.save(studentIsdetail);
});
}

How to compare Mono error to a String in Java

I have a method something like this :
public Mono<SomeDTO> DoAction(SomeDTO someDTOObject) {
return findUser(someDTOObject.getUsername())
.flatMap(existingUser -> {
Update update = new Update();
return mongoTemplate.upsert(
Query.query(Criteria.where("username").is(someDTOObject.getUsername())),
update,
SomeDTO.class,
COLLECTION_NAME);
}).switchIfEmpty(
Mono.defer(() -> {
return Mono.error(new Exception("User Name doesn't exist."));
})
);
}
For this, I have wriiten a testcase like this to test exception :
#Test
public void DoAction_TestException() {
SomeDTO someDTOObject = databaseUtil.SomeDTOMock;
Query query = Query.query(Criteria.where("username").regex("^"+userId+"$","i"));
doReturn(Mono.empty()).when(mongoTemplate).findOne(query,
SomeDTO.class, "COLLECTION_NAME");
try {
SomeDTO someDTOObjectResult = mongoImpl.DoAction(someDTOObject).block();
}
catch (Exception e) {
String expected = "User Name doesn't exist.";
String result = e.getMessage().toString(); /////// this value during debugging is "java.lang.Exception:User Name doesn't exist. "
assertEquals(expected,result);
}
}
When I run the above code , the assert is failing becuase variable result has extra string along with it. How can I remove java.lang.Exception from the result ?
I dont want to use any string functions to remove part of string.ANy help would be very helpful.

If you're already in a catch clause, you're not dealing with Mono anymore.
In debugging you're checking e.toString(), which will be "java.lang.Exception:User Name doesn't exist. ".
But try to check behavior in a more isolated way.
public static void main(String[] args) {
Exception exception = new Exception("User Name doesn't exist.");
try {
throw exception;
} catch (Exception e) {
System.out.println("getMessage: " +e.getMessage());
System.out.println("toString: " + e.toString());
}
}
In this case e.getMessage() will print as expected User Name doesn't exist.

Eugene's answer is already showing you the correct way.
Alternate Solution #1:
Create a specific Exception class: EntityNotFoundException extends IOException or UsernameNotFoundException extends IOException and test if your result is an instance of that class.
Alternate Solution #2:
Extend your expected String expected to the String you really get.
Alternate Solution #3:
(I do not know Mono, so IF:) If Mono wraps up the Exception into another exception, you probably can reach that original exception by using e.getCause: Change your line String result = e.getMessage().toString(); to String result = e.getCause().getMessage();.
To help us find that out, simply add the line e.printStackTrace(); right after your line String expected = "User Name doesn't exist.";, and then show us what error message was printed. From there on we can help further, if the other solutions have not helped yet.

Update row if references is exist, otherwise delete using spring boot

Need guideline -
How to do hard delete when no reference is available and do soft delete when reference is available, this operation should be performed in a single method itself.
E.g.
I have 1 master table and 3 transactional tables and the master reference is available in all 3 transactional tables.
Now while deleting master row - I have to do the following: If master reference is available then update the master table row and if no master ref. is available delete the row.
I tried following so far.
Service Implementation -
public response doHardOrSoftDelete(Employee emp) {
boolean flag = iMasterDao.isDataExist(emp);
if(flag) {
boolean result = iMasterDao.doSoftDelete(emp);
} else {
boolean result = iMasterDao.doHardDelete(emp);
}
}
Second Approach:
As we know that while deleting a record if the reference is available then it throws ConstraintViolationException so simply we can catch it and check that caught exception is of type ConstraintViolationException or not, if yes then call doSoftDelete() method and return the response. So here you don't need to write method or anything to check the references. But I'm not sure whether it is the right approach or not. Just help me with it.
Here is what I tried again -
public Response deleteEmployee(Employee emp) {
Response response = null;
try{
String status= iMasterDao.deleteEmployeeDetails(emp);
if(status.equals("SUCCESS")) {
response = new Response();
response.setStatus("Success");
response.setStatusCode("200");
response.setResult("True");
response.setReason("Record deleted successfully");
return response;
}else {
response = new Response();
response.setStatus("Fail");
response.setStatusCode("200");
response.setResult("False");
}
}catch(Exception e){
response = new Response();
Throwable t =e.getCause();
while ((t != null) && !(t instanceof ConstraintViolationException)) {
t = t.getCause();
}
if(t instanceof ConstraintViolationException){
boolean flag = iMasterDao.setEmployeeIsDeactive(emp);
if(flag) {
response.setStatus("Success");
response.setStatusCode("200");
response.setResult("True");
response.setReason("Record deleted successfully");
}else{
response.setStatus("Fail");
response.setStatusCode("200");
response.setResult("False");
}
}else {
response.setStatus("Fail");
response.setStatusCode("500");
response.setResult("False");
response.setReason("# EXCEPTION : " + e.getMessage());
}
}
return response;
}
Dao Implementation -
public boolean isDataExist(Employee emp) {
boolean flag = false;
List<Object[]> tbl1 = session.createQuery("FROM Table1 where emp_id=:id")
.setParameter("id",emp.getId())
.getResultList();
if(!tbl1.isEmpty() && tbl1.size() > 0) {
flag = true;
}
List<Object[]> tbl2 = session.createQuery("FROM Table2 where emp_id=:id")
.setParameter("id",emp.getId())
.getResultList();
if(!tbl2.isEmpty() && tbl2.size() > 0) {
flag = true;
}
List<Object[]> tbl3 = session.createQuery("FROM Table3 where emp_id=:id")
.setParameter("id",emp.getId())
.getResultList();
if(!tbl3.isEmpty() && tbl3.size() > 0) {
flag = true;
}
return flag;
}
public boolean doSoftDelete(Employee emp) {
empDet = session.get(Employee.class, emp.getId());
empDet .setIsActive("N");
session.update(empDet);
}
public boolean doHardDelete(Employee emp) {
empDet = session.get(Employee.class, emp.getId());
session.delete(empDet);
}
No matter how many transactional tables will be added with master tbl reference, my code should do the operations(soft/hard delete) accordingly.
In my case, every time new transactional tables get added with a master reference I've do the checks, so Simply I want to skip the isDataExist() method and do the deletions accordingly, how can I do it in a better way?
Please help me with the right approach to do the same.

There's a lot of repeated code in the body of isDataExist() method which is both hard to maintain and hard to extend (if you have to add 3 more tables the code will double in size).
On top of that the logic is not optimal as it will go over all tables even if the result from the first one is enough to return true.
Here is a simplified version (please note that I haven't tested the code and there could be errors, but it should be enough to explain the concept):
public boolean isDataExist(Employee emp) {
List<String> tableNames = List.of("Table1", "Table2", "Table3");
for (String tableName : tableNames) {
if (existsInTable(tableName, emp.getId())) {
return true;
}
}
return false;
}
private boolean existsInTable(String tableName, Long employeeId) {
String query = String.format("SELECT count(*) FROM %s WHERE emp_id=:id", tableName);
long count = (long)session
.createQuery(query)
.setParameter("id", employeeId)
.getSingleResult();
return count > 0;
}
isDataExist() contains a list of all table names and iterates over these until the first successful encounter of the required Employee id in which case it returns true. If not found in any table the method returns false.
private boolean existsInTable(String tableName, Long employeeId) is a helper method that does the actual search for employeeId in the specified tableName.
I changed the query to just return the count (0 or more) instead of a the actual entity objects as these are not required and there's no point to fetch them.
EDIT in response to the "Second approach"
Is the Second Approach meeting the requirements?
If so, then it is a "right approach" to the problem. :)
I would refactor the deleteEmployeeDetails method to either return a boolean (if just two possible outcomes are expected) or to return a custom Enum as using a String here doesn't seem appropriate.
There is repeated code in deleteEmployeeDetails and this is never a good thing. You should separate the logic which decides the type of the response from the code that builds it, thus making your code easier to follow, debug and extend when required.
Let me know if you need a code example of the ideas above.
EDIT #2
Here is the sample code as requested.
First we define a Status enum which should be used as return type from MasterDao's methods:
public enum Status {
DELETE_SUCCESS("Success", "200", "True", "Record deleted successfully"),
DELETE_FAIL("Fail", "200", "False", ""),
DEACTIVATE_SUCCESS("Success", "200", "True", "Record deactivated successfully"),
DEACTIVATE_FAIL("Fail", "200", "False", ""),
ERROR("Fail", "500", "False", "");
private String status;
private String statusCode;
private String result;
private String reason;
Status(String status, String statusCode, String result, String reason) {
this.status = status;
this.statusCode = statusCode;
this.result = result;
this.reason = reason;
}
// Getters
}
MasterDao methods changed to return Status instead of String or boolean:
public Status deleteEmployeeDetails(Employee employee) {
return Status.DELETE_SUCCESS; // or Status.DELETE_FAIL
}
public Status deactivateEmployee(Employee employee) {
return Status.DEACTIVATE_SUCCESS; // or Status.DEACTIVATE_FAIL
}
Here is the new deleteEmployee() method:
public Response deleteEmployee(Employee employee) {
Status status;
String reason = null;
try {
status = masterDao.deleteEmployeeDetails(employee);
} catch (Exception e) {
if (isConstraintViolationException(e)) {
status = masterDao.deactivateEmployee(employee);
} else {
status = Status.ERROR;
reason = "# EXCEPTION : " + e.getMessage();
}
}
return buildResponse(status, reason);
}
It uses two simple utility methods (you can make these static or export to utility class as they do not depend on the internal state).
First checks if the root cause of the thrown exception is ConstraintViolationException:
private boolean isConstraintViolationException(Throwable throwable) {
Throwable root = throwable;
while (root != null && !(root instanceof ConstraintViolationException)) {
root = root.getCause();
}
return root != null;
}
And the second one builds the Response out of the Status and a reason:
private Response buildResponse(Status status, String reason) {
Response response = new Response();
response.setStatus(status.getStatus());
response.setStatusCode(status.getStatusCode());
response.setResult(status.getResult());
if (reason != null) {
response.setReason(reason);
} else {
response.setReason(status.getReason());
}
return response;
}
If you do not like to have the Status enum loaded with default Response messages, you could strip it from the extra info:
public enum Status {
DELETE_SUCCESS, DELETE_FAIL, DEACTIVATE_SUCCESS, DEACTIVATE_FAIL, ERROR;
}
And use switch or if-else statements in buildResponse(Status status, String reason) method to build the response based on the Status type.

String values are persisted with double quotes in table using Spring JPA

We are using Spring JPA with MySQL. While inserting values into the table, the string values are inserted with double quotes. Kindly let me know how to resolve this issue.
We are using MySQL 8, spring-boot-starter-data-jpa-2.0.1.RELEASE.jar and Java 11.
#Override
public Response createNamespace(Namespace namespaceDto) throws AdminException {
try {
com.###.tcp.ens.adminservice.entity.Namespace namespace =
new com.###.tcp.ens.adminservice.entity.Namespace();
namespace.setNamespace(namespaceDto.getNameSpace());
namespace.setAssociatedAppTrn(namespaceDto.getAssociatedAppTrn());
namespace.setAdmins(namespaceDto.getAdminUser());
if (namespaceRepository.findByNamespace(namespaceDto.getNameSpace()).isPresent()) {
return AdminHelper.exceptionHandler(new Exception(),
HttpStatus.UNPROCESSABLE_ENTITY,
AdminStatus.NAMESPACE_EXISTS,
AdminStatus.NAMESPACE_EXISTS.message());
} else {
namespaceRepository.save(namespace);
return Response.status(HttpStatus.CREATED.value()).entity(namespace).build();
}
} catch (DataAccessResourceFailureException exception) {
return AdminHelper.exceptionHandler(exception, HttpStatus.INTERNAL_SERVER_ERROR,
AdminStatus.NAMESPACE_CREATE_FAILED,
AdminStatus.NAMESPACE_CREATE_FAILED.message());
}
}
Expected output is :
'58', 'com.test.tcp3', 'some text5,some text6'
Actual output is :
'57', '\"com.test.tcp3\"', '\"some text5,some text6\"'

Removing/deleting from google datastore using endpoints, illegal arguement exception, delete with non-zero content length not supported

I'm trying to delete objects from the datastore (using cloud endpoints)
I know the connection is valid because I'm pulling/inserting objects with no problem
However when I try to delete using various approaches I get the same exception
java.lang.illegalArgumentException:DELETE with non-zero content length is not supported
approach 1(using the raw datastore service and the key I stored when inserting the item):
#ApiMethod(name = "removeRPurchase")
public RPurchase removeRPurchase(RPurchase purchase) {
NamespaceManager.set(purchase.getAccount());
DatastoreService d=DatastoreServiceFactory.getDatastoreService();
Key k=KeyFactory.stringToKey(purchase.getKeyrep());
try {
d.delete(k);
} catch (Exception e) {
e.printStackTrace();
purchase=null;
}
return purchase;
}
Approach 2
#ApiMethod(name = "removeRPurchase")
public RPurchase removeRPurchase(RPurchase purchase) {
NamespaceManager.set(purchase.getAccount());
Key k=KeyFactory.stringToKey(purchase.getKeyrep());
EntityManager mgr = getEntityManager();
RPurchase removed=null;
try {
RPurchase rpurchase = mgr.find(RPurchase.class, k);
mgr.remove(rpurchase);
removed=rpurchase;
} finally {
mgr.close();
}
return removed;
}
Ive also tried various variations with the entity manager and the Id, but all with the same exception
The object that i've passed in does contain the namespace in the account, and it does contain the 'KeytoString' of the key associated with the object
the endpoint is called as it should in an AsyncTask endpoint.removeRPurchase(p).execute();
Any help suggestions are appreciated

Make your API method a POST method like this:
#ApiMethod(name = "removeRPurchase" path = "remove_r_purchase", httpMethod = ApiMethod.HttpMethod.POST)
public RPurchase removeRPurchase(RPurchase purchase) {
NamespaceManager.set(purchase.getAccount());
DatastoreService d=DatastoreServiceFactory.getDatastoreService();
Key k=KeyFactory.stringToKey(purchase.getKeyrep());
try {
d.delete(k);
} catch (Exception e) {
e.printStackTrace();
purchase=null;
}
return purchase;
}
I had the same problem because I was using httpMethod = ApiMethod.HttpMethod.DELETE. The error it gives is correct. Simply change it to a POST and do whatever you want inside that API method like delete entities, return entities, etc.

How about trying out the following :
#ApiMethod(
name = "removeRPurchase",
httpMethod = HttpMethod.DELETE
)
public void removeRPurchase(#Named("id") String id) {
//Now take the id and plugin in your datastore code to retrieve / delete
}