When sending an Object to a JSP page the persistent and transient fields are left out. I can see on the Java side these variables are filled in with data, but once it gets to the JSP page some of the values are missing, specifically every field that is not mapped to a column.
Group Entity
#Entity
#Table(name="groups")
#XmlRootElement
public class Groups {
#Id
#GeneratedValue(strategy=GenerationType.SEQUENCE,generator="groupsSeqGen")
//TODO: I dont think H2 is having the sequences auto generated. Need to add these manually.
#SequenceGenerator(name="groupsSeqGen",sequenceName="groups_sequence", initialValue = 10, allocationSize = 100)
private Long id;
#Column(name="name")
private String name;
#Column(name="create_date")
private Date createDate;
#Column(name="owner_user")
private String ownerUser;
#Column(name="is_public")
private Boolean isPublic;
#Column(name="description")
private String description;
#OneToMany(fetch = FetchType.EAGER, mappedBy = "ownerGroup")
private List<Books> books;
}
Request Mapping
#RequestMapping("/Mygroups")
public ModelAndView getMyGroup() {
ModelAndView mav=new ModelAndView();
mav.addObject("groups", appservice.findMyGroups()); //This returns the groups!
mav.setViewName("myGroups");
return mav;
}
My JSP page can read the groups. Just for an idea here is the console output when I print the object.
Groups [id=1, name=Club 1, createDate=2019-08-01 00:00:00.0, description=Club 1 desc, isPublic=true, ownerUser=user1]
What i've tried.
Adding #transient and #XMLTransient tags.
Joining columns differently.
Changing the Fetch type (This doesnt matter im just changing random things at this point)
The other Odd Part is when I write to the object with a form I can set these fields fine! Maybe its because Javascript is just setting the fields regardless of if it matches and when Java reads it in when it does match it works correctly?
I'm an idiot....
It didn't show up in my JavaScript console output because I skipped adding it to the ToString in my Groups class. Once I added it there. I realized I was just referencing it incorrectly in JavaScript.I think I was referencing it as "books" instead of "group.books" and didn't realize because I was printing the object and it wasn't there.
Related
I have a requirement to mark certain properties in my REST beans as ignored using #JsonIgnore. (I am using Spring Boot). This helps in avoiding these properties in my Swagger REST documentation.
I also would like to ensure that if the client passes these properties, an error is sent back. I tried setting spring.jackson.deserialization.fail-on-unknown-properties=true, but that works only for properties that are truly unknown. The properties marked with #JsonIgnore passes through this check.
Is there any way to achieve this?
I think I found a solution -
If I add #JsonProperty(access = Access.READ_ONLY) to the field that is marked as #JsonIgnore, I get back a validation error. (I have also marked the property with #Null annotation. Here is the complete solution:
#JsonInclude(JsonInclude.Include.NON_NULL)
public class Employee {
#Null(message = "Id must not be passed in request")
private String id;
private String name;
//getters and setters
}
#JsonInclude(JsonInclude.Include.NON_NULL)
public class EmployeeRequest extends Employee {
#Override
#JsonIgnore
#JsonProperty(access = Access.READ_ONLY)
public void setId(String id) {
super.setId(id);
}
}
PS: By adding #JsonProperty(access = Access.READ_ONLY), the property started showing up in Swagger model I had to add #ApiModelProperty(hidden = true) to hide it again.
The create method takes EmployeeRequest as input (deserialization), and the get method returns Employee as response (serialization). If I pass id in create request, with the above solution, it gives me back a ConstraintViolation.
PS PS: Bummer. None of these solutions worked end-to-end. I ended up creating separate request and response beans - with no hierarchical relationship between them.
I see in most of the coders save data(using spring data) as:
savedEntity = repo.save(savedEntity);
Long id = savedEntity.getId();
I am confused about why most of them assign back the returned value to the saved Entity while the following code also works exact(I have tested myself):
repo.save(savedEntity);
Long id = savedEntity.getId();
Did I miss some benefit of assigning back?
for example, let the entity be:
#Entity
public class SavedEntity {
#Id
private int id;
private String name;
//getter, setters, all arg-constructor, and no-arg constructor
}
Consider the object of SavedEntity is
SavedEntity entity = new SavedEntity(1,"abcd");
now for your first question,
SavedUser entity1 = repo.save(entity);
Long id = entity1.getId();
this entity1 object is the return object getting from the database, which means the above entity is saved in the database succesfully.
for the Second Question,
repo.save(entity);
Long id = entity.getId();//which you got it from SavedEntity entity = new SavedEntity(1,"abcd");
here the value of id is the integer you mentioned in place of id(the raw value).
Most of the time the id (primary key) is generated automatically while storing the entity to the database using strategies like AUTO, Sequence etc. So as to fetch those id's or autogenerated primary key values we assign back the saved entity.
For example:
#Entity
public class Customer {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String firstName;
private String lastName;
}
In this case you'll not pass the id externally but it will create a value for it automatically while storing the data to DB.
Our application uses PagingAndSortingRepository to serve our REST API. This works great, but we ran into a specific edge case that we can't seem to solve:
We have a alphanumeric field that has to be sortable (e.g. SOMETHING-123). One possible solution was to use something like a regex inside the database query's order by. This was ruled out, as we wanted to stay database independant. Thus we split up the column into two columns.
So before we had an Entity with 1 String field:
#Entity
public class TestingEntity {
#Id
#GeneratedValue
private long id;
private String alphanumeric
}
And now we have an Entity with 2 additional fields and the old field made #Transient which is filled at #PostLoad:
#Entity
public class Testing {
#Id
#GeneratedValue
private long id;
#Transient
public String alphanumeric;
#PostLoad
public void postLoad(){
this.alphanumeric = this.alphabetic + "-" + this.numeric;
}
public void setAlphanumeric(String alphanumeric) {
int index = alphanumeric.indexOf("-");
this.alphabetic = alphanumeric.substring(0, index);
this.numeric = Long.parseLong(alphanumeric.substring(index + 1));
}
#JsonIgnore
private String alphabetic;
#JsonIgnore
private Long numeric;
}
This is working great and the additional fields do not get exposed. However the sorting on the field "alphanumeric" does obviously not work anymore. The simplest solution would be to make this request:
localhost:8080/api/testingEntity?sort=alphanumeric,asc
and internally rewrite it to the working request:
localhost:8080/api/testingEntity?sort=alphabetic,asc&sort=numeric,asc
What is the best way to tackle this issue?
I have an entity model, for simplification purposes let's say it looks like this :
public class Results {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private Long firstUser;
private Long secondUser;
private Double average;
private Double median;
private Double score;
}
This is my ResultsService Implementation:
public class ResultsServiceImpl implements ResultsService{
#Autowired
private CalculateDataRepository calculateDataRepository;;
#Autowired
private ResultsService resultsService;
Results results=new Results();
public void Average(Long id1, Long id2){
UserData firstClient = calculateDataRepository.findOne(id1);
userData secondClient = calculateDataRepository.findOne(id2);
clientId = firstClient.getClient().getId();
secondId = secondClient.getClient().getId();
Double average=(firstClient.getA()+secondClient.getA())/2;
results.setAverage(average);
}
public void Score(Long id1, Long id2){
SurveyData firstClient = surveyDataRepository.findOne(id1);
SurveyData secondClient = surveyDataRepository.findOne(id2);
clientId = firstClient.getClient().getId();
secondId = secondClient.getClient().getId();
Double average=(firstClient.getB()+secondClient.getB());
results.setScore(average);
results.setFirstUser(clientId );
results.setSecondUser(secondId );
resultsService.save(results);
}
....
I tried declaring Results results=new Results(); inside every method, but when I save them they get saved in different rows, instead of the same one.
How do I hold the reference so that when I call the setter of a field in one function, it's in the same row as the setter of a field in the other function.
To keep the problem focused, I tried to avoid showing the implementation of calculateDataRepository which is just the repository of an entity where some results are saved for different users.
The Results Method has no foreign field reference nor a reference from somewhere else, as there are fields firstUser and secondUser which I set from one of the methods;
Thank you.
Edit:
Results results=resultsService.findByFirstUserAndSecondUser(clientId, secondId);
if(results==null) {
results= new Results();
// Store to db ?
}
results.setAverage();
resultsService.save(results);
Actually you need a method in ResultsRepository
Results findByFirstAndSecond(Long first, Long second);
In the each Average and Score methods (BTW Java naming convention requires to have method names start from lowercase letter) call the findByFirstAndSecond(id1, id2)
If the method returns null (no such result) create a new instance and save in the DB (INSERT). If some Results is returned store the info there and save changes in DB (UPDATE).
I'm using Spring 3.1.0.RELEASE with Hibernate 4.0.1.Final. I want to invoke a search method in a controller that takes as input a search bean (the Event bean below) ...
#RequestMapping(value = "/search_results.jsp")
public ModelAndView processSearch(final HttpServletRequest request, final Event searchBean, final BindingResult result) {
...
}
The event bean contains the following field ...
#Entity
#Table(name = "EVENTS")
public class Event implements Comparable {
...
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name="EVENT_FEED_ID")
private EventFeed eventFeed;
...
}
in which the EventFeed object contains the following fields ...
#Entity
#Table(name = "EVENT_FEEDS")
public class EventFeed {
#Id
#Column(name = "ID")
#GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;
#NotEmpty
#Column(name = "TITLE")
private String title;
...
}
How do I construct a URL such that the search bean's Event.getEventFeed().getId() field is populated?
I realize I could submit a GET request with a parameter like "eventFeedId=2" and populate everything manually, but since other pages are submitting requests that populate the command object, I'd like to continue to use the same logic.
It would be
/search_results.jsp?event.eventFeed.id=...&event.eventFeed.title=...
event is a default model attribute name as defined in #ModelAttribute, other binding rules are described in 5.4.1 Setting and getting basic and nested properties.
Note, however, that this approach can cause problems if you'll associate these bean with Hibernate session later. For example, if you want to attach new Event to the existing EventFeed by calling merge() it would also override the title property. Thus, in such a case it would be better to avoid overuse of data binding and pass primitives as parameters instead.