Spring MongoDB存储库仅在某些情况下有效 [英] Spring MongoDB Repository works only in some cases
问题描述
我有一个基于jHipster的项目(Java + MongoDB + AngularJS).我正在将Mongodb与Spring MongoDB存储库一起使用,以实现数据持久性.
I have a project based on jHipster (Java + MongoDB + AngularJS). I am using mongodb with Spring MongoDB repository for data persistance.
问题在于,存储库中的相同方法(称为findOneByEntityId)在某些情况下会有所不同.
Problem is that the same method in repository (called findOneByEntityId) works different in some cases.
情况1: 角度资源要求控制器获取TermMap.上面提到的控制器使用方法.结果就是成功.
Case 1: Angular resource asks controller to fetch TermMap. Controller use method mentioned above. Result is success.
情况2: DataMapFactory尝试使用具有相同参数的相同方法并获取NullPointerException.结果就是失败.
Case 2: DataMapFactory tries to use the same method with the same parameter and get NullPointerException. Result is failure.
情况3: 我也尝试过从DataMapFactory调用控制器方法,但它也给了我NullPointerException.
Case 3: I've also tried to call controller method from DataMapFactory but it also gives me NullPointerException.
存储库代码:
package com.xxx.yyy.repository;
import com.xxx.yyy.domain.maps.TermsMap;
import org.springframework.data.mongodb.repository.MongoRepository;
public interface TermsMapRepository extends MongoRepository<TermsMap,String> {
TermsMap findOneByEntityId(String entityId);
}
带有方法的控制器代码(我去除了不必要的方法)
package com.xxx.yyy.web.rest;
import com.codahale.metrics.annotation.Timed;
import com.xxx.yyy.domain.maps.TermsMap;
import com.xxx.yyy.repository.TermsMapRepository;
import com.xxx.yyy.web.rest.util.HeaderUtil;
import com.xxx.yyy.web.rest.util.PaginationUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import javax.inject.Inject;
import javax.validation.Valid;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.List;
import java.util.Optional;
@RestController
@RequestMapping("/api")
public class TermMapResource {
private final Logger log = LoggerFactory.getLogger(TermMapResource.class);
@Inject
private TermsMapRepository tmRepository;
/**
* GET /termmaps/:id -> get the "id" company.
*/
@RequestMapping(value = "/termmaps/{id}",
method = RequestMethod.GET,
produces = MediaType.APPLICATION_JSON_VALUE)
@Timed
public ResponseEntity<TermsMap> getTM(@RequestParam(required = false) String field, @PathVariable String id) {
switch (field) {
case "entityId": log.debug("REST request to get TM by entityId: {}", id);
return Optional.ofNullable(tmRepository.findOneByEntityId(id))
.map(tm -> new ResponseEntity<>(
tm,
HttpStatus.OK))
.orElse(new ResponseEntity<>(HttpStatus.NOT_FOUND));
default: log.debug("REST request to get TM : {}", id);
return Optional.ofNullable(tmRepository.findOne(id))
.map(tm -> new ResponseEntity<>(
tm,
HttpStatus.OK))
.orElse(new ResponseEntity<>(HttpStatus.NOT_FOUND));
}
}
}
存储库代码:
package com.xxx.yyy.domain.factories;
import com.xxx.yyy.domain.maps.TermsMap;
import com.xxx.yyy.repository.TermsMapRepository;
import com.xxx.yyy.web.rest.TermMapResource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.inject.Inject;
import java.util.ArrayList;
import java.util.Optional;
public class DataMapsFactory {
private static DataMapsFactory instance;
private final Logger log = LoggerFactory.getLogger(DataMapsFactory.class);
@Inject
private TermsMapRepository termsMapRepository;
public DataMapsFactory(){
}
public static DataMapsFactory getInstance(){
if(instance == null) {
instance = new DataMapsFactory();
}
return instance;
}
public ArrayList<String> getDataMapForVehicle(String id) {
log.debug("Getting data map for: "+id);
try {
TermsMap map = termsMapRepository.findOneByEntityId(id);
log.debug("fetched map: "+map);
return map.getTermsIds();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
任何帮助将不胜感激,因为我对此非常执着. 如果您需要任何其他信息,请写:-) 感谢您提前提出所有答案.
Any help would be very appreciated since I'm pretty stuck at this. If you need any additional information just write :-) Thanks for all answers in advance.
推荐答案
如 mlk 所述,问题是我的单例实现导致弹簧容器出现问题.我已将DataMapsFactory
的代码更改为:
As mlk mentioned, problem was with my singleton implementation which caused problem to spring container. I've changed code of DataMapsFactory
to:
package com.njugroup.flotilla.domain.factories;
import com.njugroup.flotilla.domain.maps.TermsMap;
import com.njugroup.flotilla.repository.TermsMapRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import java.util.Optional;
@Component
public class DataMapsFactory{
private final Logger log = LoggerFactory.getLogger(TermsMapsFactory.class);
@Autowired
private TermsMapRepository termsMapRepository;
public TermsMap getDataMapForVehicle(String id) {
log.debug("Getting data map for: "+id);
try {
Optional<TermsMap> map = Optional.ofNullable(termsMapRepository.findOneByEntityId(id));
log.debug("fetched map: "+map);
return map.get();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
现在,它就像一种魅力.
Now it works like a charm.
这篇关于Spring MongoDB存储库仅在某些情况下有效的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!