So, i have controller, that should return List of Courses (2 course in MYSQL), where i can find Course by name.
When i run application, i don't see anything course, but i can find necessary course in the search column. Example: write "java" and application print me.
#GetMapping ("/index")
public String findCourse (Model model, #RequestParam (name="keyword", defaultValue = "") String keyword ) {
List <Course> course = courseService.findCourseBycourseName(keyword);
model.addAttribute("listCourses", course);
model.addAttribute("keyword", keyword);
return "views/courses";
}
When i change main method in Controller, i see List Course, but i can not search this course. Button search don't work.
List <Course> course = courseService.findCourseBycourseName(keyword);
to --> List <Course> course = courseService.fatchAll();
Who know where my problem, and how and where i can see what findCourseBycourseName returned me?
Service layer.
public interface CourseService {
List <Course> findCourseBycourseName(String keyword);
List <Course> fetchAll();
ServiceImpl
#Override
public List <Course> findCourseBycourseName(String keyword) {
return courseDao.findCourseBycourseName(keyword);
}
#Override
public List<Course> fetchAll() {
return courseDao.findAll();
}
And Dao
public interface CourseDao extends JpaRepository <Course, Long> {
List <Course> findCourseBycourseName (String keyword);
Related
I am developing simple spring webflux demo application with reactive mongodb and i want to read all data of Employee by name except containing name field "joe","Sara","JOE","SARA" and i have following code like:
//repository interface
public interface EmployeeRepository extends ReactiveMongoRepository<Employee, String>{
Flux<Employee> findAllByName(String name);
}
//Service class
public class EmplyeeService
{
private EmployeeRepository employeeRepository;
public Flux<Employee> findAllByOrganizationName(String name)
{
return employeeRepository.findAllByName(name);
}
public Flux<String> getAllNameExceptSome(String name)
{
Employee emp1=new Employee();
List<Flux<Employee>> emp=Arrays.asList(employeeRepository.findAllByName(name));
Flux<Flux<Employee>> emp2=Flux.fromIterable(emp)
.filter(name->name.equalsIgnoreCase("joe"));
return emp2;
}
}
First of all, unless some particular situations, you should avoid these data structures:
List<Flux<Employee>>
Flux<Flux<Employee>>
However you are not leveraging Spring Data. You can achieve you result simply changing your repository to:
public interface EmployeeRepository extends ReactiveMongoRepository<Employee, String> {
// this find all Employee except those matching names provided as param
Flux<Employee> findAllByNameNotIn(List<String> nameList);
// this find all Employee matching names provided as param
Flux<Employee> findAllByNameIn(List<String> nameList);
}
Invoking this method you will obtain the list of Employee already filtered by name.
NOTE: Go down in order to see the edited message.
I'm trying to imitate this query:
db.sentiments.aggregate([
{"$group" : {_id:{theme_id:"$theme",sentiment_id:"$sentiment"}, count:{$sum:1}}},
{"$sort":{"_id.theme_id":1}} ])
This is the code that I had generated in order to imitate it:
#RepositoryRestResource(collectionResourceRel = "sentiments", path = "sentiments")
public interface SentimentsRepository extends MongoRepository<Sentiments, String> {
Long countByTheme(#Param("theme") String theme);
#Query(value ="[\n" +
" {\"$group\" : {_id:{theme_id:\"$theme\",sentiment_id:\"$sentiment\"}, count:{$sum:1}}},\n" +
"\t{\"$sort\":{\"_id.theme_id\":1}}\n" +
"]",count = true)
List<Object> comptarSentiments();
}
Well this code is returning me this error:
"exception": "org.springframework.data.mongodb.UncategorizedMongoDbException",
"message": "Can't canonicalize query: BadValue unknown operator: $group; nested exception is com.mongodb.MongoException: Can't canonicalize query: BadValue unknown operator: $group",
Actually I'm a begginer in what refers to the use of Spring so I'm very lost, does any one know what should I do?
Thanks and sorry for my bad english, not my native language.
[EDIT]----------------------------------------
Just as the comment wrote by Shawn Clark It's not possible to do it this way, in order to achieve that you will need to create a customRepository.
What's the difference between Spring Data's MongoTemplate and MongoRepository?
I have been trying to do it this way but something doesn't seem to be correct, here is my new code:
#RepositoryRestResource(collectionResourceRel = "sentiments", path = "sentiments")
public interface SentimentsRepository extends CrudRepository<Sentiments, String>, CustomSentimentsRepository {
//Other methods...
}
public interface CustomSentimentsRepository {
List<CountResult> yourCustomMethod();
class CountResult{
String theme;
String sentiment;
int total;
}
}
public class SentimentsRepositoryImpl implements CustomSentimentsRepository {
private final MongoOperations operations;
#Autowired
public SentimentsRepositoryImpl(MongoOperations operations) {
Assert.notNull(operations, "MongoOperations must not be null!");
this.operations = operations;
}
#Override
public List<CountResult> yourCustomMethod(){
Aggregation agg = Aggregation.newAggregation(
Aggregation.group("theme","sentiment").count().as("total"),
Aggregation.project("theme","sentiment").and("total").previousOperation(),
Aggregation.sort(Sort.Direction.DESC, "theme")
);
//Convert the aggregation result into a List
AggregationResults<CountResult> groupResults
= operations.aggregate(agg,"sentiments", CountResult.class);
//List<CountResult> result = groupResults.getMappedResults();
return groupResults.getMappedResults();
}
}
I'm not even able to debbug this code and I'm always getting a 404.
Based on the information I have found you can't do that complex of a #Query on a MongoRepository method. In this case you would want to create a class and implement your comptarSentiments() method using the mongoTemplate to query the data store with your aggregate function. Then create a controller class that exposes a REST endpoint and have it call the repository.
Once you get to doing complex queries in Mongo you lose the ease of #RepositoryRestResource and have to go back to wiring the REST endpoint to the repository yourself.
Spring Data REST : custom query for MongoDB repository
Implementing custom methods of Spring Data repository and exposing them through REST
I finally managed to solve the problem, seems like it was related with the controller and the type of the atribute "total" from the innerClass CountResult, it needs to be a String (this is very important, otherwise the Aggregation.project will fail). Here goes the final code:
public interface CustomSentimentsRepository {
List<CountResult> myCountGroupByThemeAndSentiment();
class CountResult{
public String theme;
public String sentiment;
public String total;
}
}
public class SentimentsRepositoryImpl implements CustomSentimentsRepository {
private final MongoTemplate mongoTemplate;
#Autowired
public SentimentsRepositoryImpl(MongoTemplate mongoTemplate) {
this.mongoTemplate = mongoTemplate;
}
#Override
public List<CountResult> myCountGroupByThemeAndSentiment(){
Aggregation agg = Aggregation.newAggregation(
Aggregation.group("theme","sentiment").count().as("total"),
Aggregation.project("theme","sentiment").andInclude("total"),
Aggregation.sort(Sort.Direction.ASC,"theme","sentiment")
);
AggregationResults<CountResult> groupResults
= mongoTemplate.aggregate(agg,"sentiments", CountResult.class);
return groupResults.getMappedResults();
}
}
#RepositoryRestResource(collectionResourceRel = "sentiments", path = "sentiments")
public interface SentimentsRepository extends CrudRepository<Sentiments, String>, CustomSentimentsRepository {
//Other methods
}
#RestController
#RequestMapping(value = "sentiments/search")
public class ChartsController {
#Autowired
private SentimentsRepository sentimentsRepository;
#RequestMapping(value = "myCountGroupByThemeAndSentiment", method = RequestMethod.GET)
public ResponseEntity<?> yourCustomMethod() {
List<?> count=sentimentsRepository.myCountGroupByThemeAndSentiment();
return new ResponseEntity(count, HttpStatus.OK);
}
}
You can use #Aggrgation available in spring data mongodb 2.2.X versions:
#Aggregation(pipeline = {"{ '$group': { '_id' : '$lastname', names : { $addToSet : '$?0' } } }", "{ '$sort' : { 'lastname' : -1 } }"}) List<PersonAggregate> groupByLastnameAnd(String property);
I want to create a page where a person sees a list of users and there are check boxes next to each of them that the person can click to have them deleted.
In my MVC that consumes a REST API, I want to send a List of User objects to the REST API.
Can the #RequestParam annotation support that?
For example:
#RequestMapping(method = RequestMethod.DELETE, value = "/delete")
public #ResponseBody Integer delete(
#RequestParam("users") List<Users> list) {
Integer deleteCount = 0;
for (User u : list) {
if (u != null) {
repo.delete(u);
++deleteCount;
}
}
return deleteCount;
}
In the MVC client, the url would be:
List list = new ArrayList<User>();
....
String url = "http://restapi/delete?users=" + list;
Request parameters are a Multimap of String to String. You cannot pass a complex object as request param.
But if you just pass the username that should work - see how to capture multiple parameters using #RequestParam using spring mvc?
#RequestParam("users") List<String> list
But I think it would be better to just use the request body to pass information.
Spring mvc can support List<Object>, Set<Object> and Map<Object> param, but without #RequestParam.
Take List<Object> as example, if your object is User.java, and it like this:
public class User {
private String name;
private int age;
// getter and setter
}
And you want pass a param of List<User>, you can use url like this
http://127.0.0.1:8080/list?users[0].name=Alice&users[0].age=26&users[1].name=Bob&users[1].age=16
Remember to encode the url, the url after encoded is like this:
http://127.0.0.1:8080/list?users%5B0%5D.name=Alice&users%5B0%5D.age=26&users%5B1%5D.name=Bob&users%5B1%5D.age=16
Example of List<Object>, Set<Object> and Map<Object> is displayed in my github.
Just a reminder, any List of custom objects might require custom converters to be registered, like:
#Bean
public Converter<String, CustomObject> stringToCustomObjectConverter() {
return new Converter<>() {
#Override
public CustomObject convert(String str) {
return new ObjectMapper().readValue(str, CustomObject.class);
}
};
}
#Bean
public Converter<String, List<CustomObject>> stringToListCustomObjectConverter() {
return new Converter<>() {
#Override
public List<CustomObject> convert(String str) {
return new ObjectMapper().readValue(str, new TypeReference<>() {
});
}
};
}
So you can cover custom cases like:
/api/some-api?custom={"name":"Bla 1","age":20}
/api/some-api?custom={"name":"Bla 1","age":20}&custom={"name":"Bla 2","age":30}
/api/some-api?custom=[{"name":"Bla 1","age":20},{"name":"Bla 2","age":30}]
where: #RequestParam("custom") List customObjects
I have a domain with uml diagram
here.
I have declared JpaRepositoryes for classes: Invoice, Contract, Consultant, User, Region
I don't want to expose the repositories as they are because I will need to wrap some business rules around them.
I have defined a few projections and they seem to work with my repositories yet they do not kick in with my #RestController
Here is a draft of my wrapper:
#RestController
#RequestMapping("/contractService")
public class ContractServiceImpl extends ServiceImpl<Contract, Long> implements IService<Contract, Long>
{
#RequestMapping("/all")
public List<Contract> all()
{
return findAll();
}
#RequestMapping(value = "/one", method = GET)
public Contract one(#RequestParam(value = "id", defaultValue = "1") Long id)
{
log.info(format("id=%d", id));
return repository.getOne(id);
}
#Autowired
RepositoryRestConfiguration rrc;
#RequestMapping("config")
public List<String> getConfig()
{
return rrc.projectionConfiguration()
.getProjectionsFor(Contract.class)
.entrySet().stream()
.map(e -> e.getKey() + "->" + e.getValue())
.collect(Collectors.toList());
}
Here the last method is to verify if projections got configured. i.e.:
http://localhost:8080/invoiceapi/contractService/config
gets me the result as:
[
"brief->interface e.invoice.entity.projection.Brief",
"contractEdit->interface e.invoice.entity.projection.ContractEdit"
]
My projection is defined as:
#Projection(name="brief", types={Contract.class, Consultant.class, User.class, Region.class})
public interface Brief
{
public Long getId();
public String getName();
}
Rest calls into repository directly returns me the projected results as desired, id and name only:
http://localhost:8080/invoiceapi/contracts?projection=brief
http://localhost:8080/invoiceapi/contracts/1?projection=brief
However those into my controller:
http://localhost:8080/invoiceapi/contractService/all?projection=brief
http://localhost:8080/invoiceapi/contractService/one?id=2&projection=brief
they recursively spider all reachable entities as far as the defined JpaRepositories go. (The Application objects below User do not show up)
My controller returns a document with Content-Type: application/json while JpaRepository based one returns a cool looking Content-Type: application/hal+json. Their output are different as well: My controller returns a more straightforward output while JpaRepository based one puts associated objects into an array called _embedded.
I'm using Spring 4.0.0.RELEASE, Spring Data Commons 1.7.0.M1, Spring Hateoas 0.8.0.RELEASE
My resource is a simple POJO:
public class UserResource extends ResourceSupport { ... }
My resource assembler converts User objects to UserResource objects:
#Component
public class UserResourceAssembler extends ResourceAssemblerSupport<User, UserResource> {
public UserResourceAssembler() {
super(UserController.class, UserResource.class);
}
#Override
public UserResource toResource(User entity) {
// map User to UserResource
}
}
Inside my UserController I want to retrieve Page<User> from my service and then convert it to PagedResources<UserResource> using PagedResourcesAssembler, like displayed here: https://stackoverflow.com/a/16794740/1321564
#RequestMapping(value="", method=RequestMethod.GET)
PagedResources<UserResource> get(#PageableDefault Pageable p, PagedResourcesAssembler assembler) {
Page<User> u = service.get(p)
return assembler.toResource(u);
}
This doesn't call UserResourceAssembler and simply the contents of User are returned instead of my custom UserResource.
Returning a single resource works:
#Autowired
UserResourceAssembler assembler;
#RequestMapping(value="{id}", method=RequestMethod.GET)
UserResource getById(#PathVariable ObjectId id) throws NotFoundException {
return assembler.toResource(service.getById(id));
}
The PagedResourcesAssembler wants some generic argument, but then I can't use T toResource(T), because I don't want to convert my Page<User> to PagedResources<User>, especially because User is a POJO and no Resource.
So the question is: How does it work?
EDIT:
My WebMvcConfigurationSupport:
#Configuration
#ComponentScan
#EnableHypermediaSupport
public class WebMvcConfig extends WebMvcConfigurationSupport {
#Override
protected void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
argumentResolvers.add(pageableResolver());
argumentResolvers.add(sortResolver());
argumentResolvers.add(pagedResourcesAssemblerArgumentResolver());
}
#Bean
public HateoasPageableHandlerMethodArgumentResolver pageableResolver() {
return new HateoasPageableHandlerMethodArgumentResolver(sortResolver());
}
#Bean
public HateoasSortHandlerMethodArgumentResolver sortResolver() {
return new HateoasSortHandlerMethodArgumentResolver();
}
#Bean
public PagedResourcesAssembler<?> pagedResourcesAssembler() {
return new PagedResourcesAssembler<Object>(pageableResolver(), null);
}
#Bean
public PagedResourcesAssemblerArgumentResolver pagedResourcesAssemblerArgumentResolver() {
return new PagedResourcesAssemblerArgumentResolver(pageableResolver(), null);
}
/* ... */
}
SOLUTION:
#Autowired
UserResourceAssembler assembler;
#RequestMapping(value="", method=RequestMethod.GET)
PagedResources<UserResource> get(#PageableDefault Pageable p, PagedResourcesAssembler pagedAssembler) {
Page<User> u = service.get(p)
return pagedAssembler.toResource(u, assembler);
}
You seem to have already found out about the proper way to use but I'd like to go into some of the details here a bit for others to find as well. I went into similar detail about PagedResourceAssembler in this answer.
Representation models
Spring HATEOAS ships with a variety of base classes for representation models that make it easy to create representations equipped with links. There are three types of classes provided out of the box:
Resource - an item resource. Effectively to wrap around some DTO or entity that captures a single item and enriches it with links.
Resources - a collection resource, that can be a collection of somethings but usually are a collection of Resource instances.
PagedResources - an extension of Resources that captures additional pagination information like the number of total pages etc.
All of these classes derive from ResourceSupport, which is a basic container for Link instances.
Resource assemblers
A ResourceAssembler is now the mitigating component to convert your domain objects or DTOs into such resource instances. The important part here is, that it turns one source object into one target object.
So the PagedResourcesAssembler will take a Spring Data Page instance and transform it into a PagedResources instance by evaluating the Page and creating the necessary PageMetadata as well as the prev and next links to navigate the pages. By default - and this is probably the interesting part here - it will use a plain SimplePagedResourceAssembler (an inner class of PRA) to transform the individual elements of the page into nested Resource instances.
To allow to customize this, PRA has additional toResource(…) methods that take a delegate ResourceAssembler to process the individual items. So you end up with something like this:
class UserResource extends ResourceSupport { … }
class UserResourceAssembler extends ResourceAssemblerSupport<User, UserResource> { … }
And the client code now looking something like this:
PagedResourcesAssembler<User> parAssembler = … // obtain via DI
UserResourceAssembler userResourceAssembler = … // obtain via DI
Page<User> users = userRepository.findAll(new PageRequest(0, 10));
// Tell PAR to use the user assembler for individual items.
PagedResources<UserResource> pagedUserResource = parAssembler.toResource(
users, userResourceAssembler);
Outlook
As of the upcoming Spring Data Commons 1.7 RC1 (and Spring HATEOAS 0.9 transitively) the prev and next links will be generated as RFC6540 compliant URI templates to expose the pagination request parameters configured in the HandlerMethodArgumentResolvers for Pageable and Sort.
The configuration you've shown above can be simplified by annotating the config class with #EnableSpringDataWebSupport which would let you get rid off all the explicit bean declarations.
I wanted to convert list of Resources to page. but when giving it PagedResourcesAssembler it was eating up the internal links.
This will get your List paged.
public class JobExecutionInfoResource extends ResourceSupport {
private final JobExecutionInfo jobExecution;
public JobExecutionInfoResource(final JobExecutionInfo jobExecution) {
this.jobExecution = jobExecution;
add(ControllerLinkBuilder.linkTo(methodOn(JobsMonitorController.class).get(jobExecution.getId())).withSelfRel()); // add your own links.
}
public JobExecutionInfo getJobExecution() {
return jobExecution;
}
}
Paged resource Providing ResourceAssembler telling Paged resource to use it, which does nothing simply return's it back as it is already a resource list that is passed.
private final PagedResourcesAssembler<JobExecutionInfoResource> jobExecutionInfoResourcePagedResourcesAssembler;
public static final PageRequest DEFAULT_PAGE_REQUEST = new PageRequest(0, 20);
public static final ResourceAssembler<JobExecutionInfoResource, JobExecutionInfoResource> SIMPLE_ASSEMBLER = entity -> entity;
#GetMapping("/{clientCode}/{propertyCode}/summary")
public PagedResources<JobExecutionInfoResource> getJobsSummary(#PathVariable String clientCode, #PathVariable String propertyCode,
#RequestParam(required = false) String exitStatus,
#RequestParam(required = false) String jobName,
Pageable pageRequest) {
List<JobExecutionInfoResource> listOfResources = // your code to generate the list of resource;
int totalCount = 10// some code to get total count;
Link selfLink = linkTo(methodOn(JobsMonitorController.class).getJobsSummary(clientCode, propertyCode, exitStatus, jobName, DEFAULT_PAGE_REQUEST)).withSelfRel();
Page<JobExecutionInfoResource> page = new PageImpl<>(jobExecutions, pageRequest, totalCount);
return jobExecutionInfoResourcePagedResourcesAssembler.toResource(page, SIMPLE_ASSEMBLER, selfLink);
}
ALTERNATIVE WAY
Another way is use the Range HTTP header (read more in RFC 7233). You can define HTTP header this way:
Range: resources=20-41
That means, you want to get resource from 20 to 41 (including). This way allows consuments of API receive exactly defined resources.
It is just alternative way. Range is often used with another units (like bytes etc.)
RECOMMENDED WAY
If you wanna work with pagination and have really applicable API (hypermedia / HATEOAS included) then I recommend add Page and PageSize to your URL. Example:
http://host.loc/articles?Page=1&PageSize=20
Then, you can read this data in your BaseApiController and create some QueryFilter object in all your requests:
{
var requestHelper = new RequestHelper(Request);
int page = requestHelper.GetValueFromQueryString<int>("page");
int pageSize = requestHelper.GetValueFromQueryString<int>("pagesize");
var filter = new QueryFilter
{
Page = page != 0 ? page : DefaultPageNumber,
PageSize = pageSize != 0 ? pageSize : DefaultPageSize
};
return filter;
}
Your api should returns some special collection with information about number of items.
public class ApiCollection<T>
{
public ApiCollection()
{
Data = new List<T>();
}
public ApiCollection(int? totalItems, int? totalPages)
{
Data = new List<T>();
TotalItems = totalItems;
TotalPages = totalPages;
}
public IEnumerable<T> Data { get; set; }
public int? TotalItems { get; set; }
public int? TotalPages { get; set; }
}
Your model classes can inherit some class with pagination support:
public abstract class ApiEntity
{
public List<ApiLink> Links { get; set; }
}
public class ApiLink
{
public ApiLink(string rel, string href)
{
Rel = rel;
Href = href;
}
public string Href { get; set; }
public string Rel { get; set; }
}