I want to obtain the maximum value of the field code within my User entity, using Spring Data and MongoDB.
I have seen similar examples using as below,
".find({}).sort({"updateTime" : -1}).limit(1)"
But have no idea how to integrate it into my own repository using the #Query annotation.
Any alternative solution, than to return the maximum value of said field is also welcome.
Thank you.
You can write a custom method for your repository.
For example you have:
public interface UserRepository extends MongoRepository<User, String>, UserRepositoryCustom {
...
}
Additional methods for repository:
public interface UserRepositoryCustom {
User maxUser();
}
And then implementation of it:
public class UserRepositoryImpl implements UserRepositoryCustom {
#Autowired
private MongoTemplate mongoTemplate;
#Override
public User maxUser() {
final Query query = new Query()
.limit(1)
.with(new Sort(Sort.Direction.DESC, "updateTime"));
return mongoTemplate.findOne(query, User.class)
}
}
You can use the spring data method syntax like:
public User findTopByOrderByUpdateTimeAsc()
A reference can be found here: https://www.baeldung.com/jpa-limit-query-results#1first-ortop
Use this code in spring to get the latest updated time from mongodb: (mongoTemplate)
public List getTopPosts() {
Query query = new Query();
query.with(Sort.by(Sort.Direction.DESC, "postUploadedTime"));
return mongoTemplate.find(query,Post.class);
}
Related
I am implementing my own Activiti command intereceptor like this :
public class ActivitiCommandInterceptor extends AbstractCommandInterceptor {
private RuntimeService runtimeService;
private CommandInterceptor delegate;
public ActivitiSpringTxCommandInterceptor(RuntimeService runtimeService, CommandInterceptor delegate) {
this.runtimeService = runtimeService;
this.delegate=delegate;
}
#Override
public <T> T execute(CommandConfig config, Command<T> command) {
String myVariable = runtimeService.getVariable(<missingExecutionId>, "myVariableName");
...
}
}
Inside the execute() method I need to retrieve a variable from the execution context related to this command.
To do that, I need to have the executionId, but I can't find a way to retrieve it.
How can I get my variable from this interceptor?
Thanks
You can create a nativeExecutionQuery
This allows us to use SQL to perform operations directly on DB.
For your case, just find all the execution IDs that contains your variables, and filter them according to your need.
I am running into few issues around handling dates in my project. This is what I have.
In My Entities, I am using ZonedDateTime.
private ZonedDateTime assignedOn;
Have Configured converters in Spring to handle this
public static class ZonedDateTimeToDateConverter implements Converter {
public static final ZonedDateTimeToDateConverter INSTANCE = new ZonedDateTimeToDateConverter();
private ZonedDateTimeToDateConverter() {}
#Override
public Date convert(ZonedDateTime source) {
return source == null ? null : Date.from(source.toInstant());
}
}
public static class DateToZonedDateTimeConverter implements Converter<Date, ZonedDateTime> {
public static final DateToZonedDateTimeConverter INSTANCE = new DateToZonedDateTimeConverter();
private DateToZonedDateTimeConverter() {}
#Override
public ZonedDateTime convert(Date source) {
return source == null ? null : ZonedDateTime.ofInstant(source.toInstant(), ZoneId.systemDefault());
}
}
I see that data is stored in Mongodb as ISO date. This what i see in Mongodb.
"completed_on" : ISODate("2017-04-12T20:02:40.000+0000"),
My Question is related to querying these date fields using Spring. If I want to find all the records (equals operator) matching only the date part and not the time part, what should be the approach? I saw example in this thread
Spring data mongodb search for ISO date
Which suggest something like this.
query.addCriteria(Criteria.where("created").ne(null).andOperator(
Criteria.where("created").gte(DateUtils.getDate("2016-04-14 00:00:00", DateUtils.DB_FORMAT_DATETIME)),
Criteria.where("created").lte(DateUtils.getDate("2016-04-14 23:59:59", DateUtils.DB_FORMAT_DATETIME))
));
Just wanted to see if this is the only approach or there's another elegant way to do this?
Does Spring Data REST support adding custom behavior to single repositories with Spring Data MongoDB and exposing it as a rest resource?
For example, here is the pojo:
#Document
#Data
#EqualsAndHashCode
public class Poet {
#Id
private String id;
private String title;
private String author;
private String content;
}
And Here is the repository:
#CrossOrigin
#RepositoryRestResource
public interface PoetRepository extends MongoRepository<Poet, String>, MyPoetRepository {
}
Can I find all the distinct title attribute in the document poet by extending a custom interface? By the way, how to implement the custom interface?
I have been building a Spring based REST service using MongoDB and Spring Data - MongoDB.
See below; parts of my data model:
#Document
public class User{
.....
private List<EMail> emails;
.....
}
public class EMail {
.....
private bool defaultMail;
private String eMailAdress;
.....
}
EMail is not annotated as a MongoDb Document.
I would like to achieve following functions in the Repository.
public Boolean exists(String email);
public User getUserByEmail(String email);
I can implement simple queries using Query and the Criteria API, but have not been successful achieving above functions.
I found a answer on my own question and I would like to share.
The query should look like this:
query (where("emails").elemMatch(where("eMailAdress").is(email)))
I found the answer by reading MongoDb manual,,, which turns out is much more understandable than spring-data manual.
//lg
Howdy, ya'll! First question on StackOverflow! :-)
So here's the scenario: We're working on a web app with Silverlight 4 and using WCF RIA Services 1.0 SP1 Beta for the web service. I have my entities in the Entity Framework Designer, but I'm using a slightly-modified ADO.NET C# POCO Entity Generator template to generate the classes.
What I'd like to do is have a method inside a Domain Service with the following signature:
[EnableClientAccess]
public class ResultService : DomainService
{
[Invoke]
public SerializableResult CalculateResult(EntityOne e1, EntityTwo e2);
}
I am returning both EntityOne and EntityTwo to the client through queries in other services, like so:
[EnableClientAccess]
public class EntityOneService : DomainService
{
public IQueryable<EntityOne> GetEntityOnes();
}
[EnableClientAccess]
public class EntityOneService : DomainService
{
public IQueryable<EntityTwo> GetEntityTwos();
}
Those classes are successfully being generated in the Silverlight project. The SerializableResult does not have a key.
When I try to compile, I get the following error: "Operation named 'CalculateResult' does not conform to the required signature. Parameter types must be an entity or complex type, a collection of complex types, or one of the predefined serializable types."
In my research, the most helpful information I found were in the comments of this post by Jeff Handley.
Of note, Peter asked in a comment:
I get an 'does not conform to the required signature ...' compile error if my complex object has an [Key] Attribute. When I remove this attribute I can use the object as parameter for an Invoke operation.
Jeff's response:
This is by design. Complex objects cannot have Key properties. If you have a Key the class gets treated as an Entity.
So it sounds as if any further efforts to try to get my method to work will be futile. However, I was wondering if anyone else has come across this problem, and what they did to solve it.
Thanks very much!
I have the following and it works for me.
namespace BusinessApplication2.Web
{
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.ServiceModel.DomainServices.Hosting;
using System.ServiceModel.DomainServices.Server;
[EnableClientAccess()]
public class DomainService1 : DomainService
{
public IQueryable<EntityOne> GetEntityOnes()
{
return null;
}
public IQueryable<EntityTwo> GetEntityTwos()
{
return null;
}
[Invoke]
public SerializableResult GetSerializableResult(EntityOne one, EntityTwo two)
{
return new SerializableResult() { Result = "It woooooorrrked!" };
}
}
public class EntityOne
{
[Key]
public int Id { get; set; }
}
public class EntityTwo
{
[Key]
public int Id { get; set; }
}
public class SerializableResult
{
public string Result { get; set; }
}
}
Many thanks to Mr. Jeff Handley and Mr. Dinesh Kulkarni for the answer (through Twitter).
In order for an Entity to be used as a parameter in an invoke method, that Entity must be exposed through a query method existing within the same DomainService. The intention for this restriction is that
"Each domain service needs to be able to stand on its own."
By adding two dummy Query methods (see Jeff's answer for an example), I was able to compile my code.