I'm trying to work with an interface-based projection recursively, However it is not projecting on the appropriate subfields, but only on the whole nested object.
Consider the document / collection class:
#Document
public class Person {
private String firstName;
private String lastName;
private Address address;
static class Address {
private String zipCode, city;
// getters and setters
}
// getters and setters
}
The closed projection:
public interface PersonSummary {
String getFirstName();
AddressSummary getAddress();
interface AddressSummary {
String getCity();
}
}
However when I'm using the following repository query:
public interface PersonRepository extends ReactiveCrudRepository<Person, String> {
Flux<PersonSummary> findAll();
}
The query is executed with the following fields: fields: Document{{firstName=1, address=1}} instead of fields: Document{{firstName=1, address.city=1}}
What are we doing wrong and is there some solution how to work around this?
According to Mark Paluch (#mp911de) at Gitter this is not yet possible, so I filed an improvement request at jira.spring.io, see: https://jira.spring.io/browse/DATAMONGO-1989
Related
I'm developing an application with React mobx. I have a complex data on the Java server side. How should I keep my data in my mobx store in for this data? I've read a lot about it. But I couldn't decide how to do it.
I have lots of classes nested. I'm just writing a part.
How should I keep nested classes? Or should I use inheritance in mobx? Thank you from now.
On the Java side I am holding List of PlanManagement.
public class Template {
private String templateName;
private String templateId;
.....
}
public class Group {
private String groupId;
private String groupName;
private String groupType;
private Template template;
....
}
public class PlanManagement {
private String id;
private String text;
private Group group;
.....
}
public class PlanCore extends PlanManagement {
private PlanStatusEnum statusValue;
private String statusType;
..............
}
public class OrderCore extends PlanManagement {
private OrderStatusEnum statusValue;
private String status;
private String task;
............
}
I have referred to ->
Spring MVC how to display data from database into a table
My aim is to try and understand what is the syntax and process to create queries, and whether I'm correct.
The following code tries to display all Order entities.
#AutoWired
private OrderService orderService;
#RequestMapping("/")
//public String orderPage(Model model) {
// model.addAttribute("orderList", SomeApp.getStore().getOrderList());
// return "form/orderPage"};
// this is the code I am trying to translate below
#ResponseBody
public List<order> orderList(Map<String, Object> model) {
List<order> orderList = OrderService.findALl();
//orderRepository.findAll <- where does this come in? is it needed at all
return orderList;
}
If the Service layer is not being used, in my Repo do I only state
List<Order> findAll();
Additional Info:
Service layer is not used in this project and instead business logic will be in Controller (partly why I'm confused as to what code goes where)
You need to #Autowire the OrderRepository so that you can call orderRepository.findAll() in your Controller as shown below. For that, you also need to define the OrderRepository and Order Entity classes.
Controller:
#Controller
public class Controller {
#AutoWired
private OrderRepository orderRepository;
#RequestMapping("/")
#ResponseBody
public List<order> orderList(Map<String, Object> model) {
List<order> orderList = OrderService.findALl();
orderRepository.findAll();
return orderList;
}
}
Repository:
#Repository
public interface OrderRepository extends JpaRepository<Order, Integer> {
public Order findAll();
}
Entity:
#Entity
public class Order {
//add your entity fields with getters and setters
}
You can refer here for spring-data-jpa basic example.
I have the following object:
{
"id" : "sampleId";
foos : [{
"prop1":"value1",
"prop2":"value2"
},
{
"prop1":"value3",
"prop2":"value4"
}
]}
How can I get foos, where prop2 is value4? I'm using Spring data mongodb.
If you use spring data mongodb repositories, it can make your life easy. You will need a domain class. e.g.
public class Foo {
String prop1;
String prop2;
}
public class MyClass {
String id;
List<Foo> foos;
}
public interface MyClassRepository extends MongoRepository<MyClass, String> {
List<MyClass> findByFoosProp2(String prop2ValueToLookFor);
// assuming you can find multiple matches
}
Then simply call this method from your code
public clsss SomeBusinessClass {
#Autowired
private MyClassRepository repository;
public void mySomeBusinessMethod() {
List<MyClass> myObjects = repository.findByFoosProp2("value4");
}
}
This code will return a SampleBean with id sampleId wich will have only matching items in collection foos.
// Match one document with sampleId
Query q1 = new Query(where("id").is("sampleId"));
// match only foos with prop2 value value2
Query q2 = query(where("foos").elemMatch(where("prop2").is("value2))
BasicQuery query = new BasicQuery(q1.getQueryObject(), q2.getQueryObject());
SampleBean result = mongoTemplate.findOne(query, SampleBean.class)
I'm studying MEF, and try to use Export attribute to export a property, and import it in an other class.
But my problem is that I want to change this property and the other class can import a new value.
For example,
[Export]
public class A{
[Import("Notes")]
public string Description{get;set;}
}
[Export]
public class B{
[Export("Notes")]
public string Text{get;set;}
}
I want once I change the Text of class B, the A.Description can get changed too.
So, how can I implement this?
Any good idea?
This approach would work for most reference type but not with string which is immutable. This means that after you change the value of B.Text, the objects referenced by A.Description and B.Text will no longer be the same (you can use Object.ReferenceEquals to test this).
One way to do what you are after using MEF is to export/import a method instead of the property:
[Export]
public class A
{
public string Description { get { return GetDescription(); } }
[Import("GetNotes")]
Func<string> GetDescription;
}
[Export]
public class B
{
public string Text { get; set; }
[Export("GetNotes")]
string GetText()
{
return Text;
}
}
Finally note that there are other ways to do this. The most common in .NET is with events.
How do I obtain values of an array that is located inside a java object in a jsp page?
I have set an object attribute so that in the jsp page I can call the object like so
${obj.property}
My question is how would I obtain property String [] example from Object obj?
<c:forEach var="prop" items="${obj.example}">
<td>${prop}</td>
</c:forEach>
I get Errors that tell me the class obj.Obj does not have the property property 'example'
and obviously I don't get the data out.
Actual errors:
org.apache.jasper.JasperException: javax.el.PropertyNotFoundException: The class 'roommate.Roommate' does not have the property 'favProfessors'.
javax.el.PropertyNotFoundException: The class 'roommate.Roommate' does not have the property 'favProfessors'
And my actual class:
package roommate;
public class Roommate{
public String firstname;
public String lastname;
public String gender;
public String place;
public String[] favProfessors;
public Roommate(String fname, String lname, String roommateGender, String hangout,String[] professors) {
firstname= fname;
lastname= lname;
gender= roommateGender;
place= hangout;
favProfessors= professors;
}
public String getFirstname()
{
return firstname;
}
public void setFirstname(String newFirstname)
{
this.firstname = newFirstname;
}
public String getLastname()
{
return lastname;
}
public void setLastname(String newLastname)
{
this.lastname = newLastname;
}
public String getGender()
{
return gender;
}
public void setGender(String newGender)
{
this.gender = newGender;
}
public String getHangout()
{
return place;
}
public void setHangout(String newPlace)
{
this.place = newPlace;
}
public String[] getProfessors()
{
return favProfessors;
}
public void setProfessors(final String[] newfavProfessors)
{
this.favProfessors = newfavProfessors;
}
public void addRoommate(String fname, String lname, String roommateGender, String hangout,String[] professors)
{
}
}
I create the object in my servlet as well ass the Atrribute
String [] profArray = request.getParameterValues("professor");
Roommate roommate= new Roommate(
session.getAttribute("fname").toString(),
session.getAttribute("lname").toString(),
session.getAttribute("gender").toString(),
session.getAttribute("hangout").toString(),
profArray);
session.setAttribute("roommate",roommate);
I asked this earlier but did not receive a clear answer. I think my issue is in pulling the data out in the jsp alone in my forEach that I mentioned at the top
javax.el.PropertyNotFoundException: The class 'roommate.Roommate' does not have the property 'favProfessors'
Java is right. You do not have a getFavProfessors() method in that class. It's instead the following:
public String[] getProfessors()
{
return favProfessors;
}
You have 2 options: use ${roommate.professors} instead, or fix the getter method name to be getFavProfessors().
In contrary to what most starters think, EL does not access private properties directly. EL just calls the public getter/setter methods according the Javabeans specification. The real private property behind it can have a completely different name or even not exist at all.