如何处理JSP文件中的@RequestParam？

Question

everyone! I have a question about using @RequestParam in @RestController. I would like to know how to get @RequestParam from client. Server code (@RestController):

@ResponseBody
@RequestMapping(method = RequestMethod.GET)
public ResponseEntity<List<ProjectBean>> getAllBeans(@RequestParam(name = "head") Integer headId) {
    Integer head = securityService.getLoggedAccountId();
    List<ProjectBean> projects = (List<ProjectBean>) projectService.getByHead(head);
    return new ResponseEntity<List<ProjectBean>>(projects, HttpStatus.OK);
}

And JSP/JavaScript:

function loadProjects() {
    $.ajax({
        url : 'rest/projects',
        method : 'GET',
        headers : {
            'Content-Type' : 'application/json',
        },
        success: function(data){
            $.each(data, function(index, project) {
                addProject(project);
            });
        }
    });
}

this function loads all projects, but not with exact headId

Entity:

@Entity
@Table(name = "projects")

public class Project {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

    @Column(name = "project_name", nullable = false, length = 255)
    private String projectName;

    @Column(name="head")
    private Integer head; //need to get projects with this value

    @Column(name = "description")
    private String description;

    @Column(name = "photo")
    private String photo;

    @Column(name = "status", nullable = false, length = 200)
    private String status;
}

Answer 1

In my opinion @NayoR's suggestion is recommended. But to actually anwser your question you need to use a query string in your js, example:

function loadProjects() {
    $.ajax({
        url : 'rest/projects?head=' + headId,
        method : 'GET',
        headers : {
            'Content-Type' : 'application/json',
        },
        success: function(data){
            $.each(data, function(index, project) {
                addProject(project);
            });
        }
    });
}

Answer 2

You may set a path in @RequestMapping annotation ;

@RequestMapping(method = RequestMethod.GET, path = "rest/projects/{head}")

or using @GetMapping annotation:

@GetMapping(path = "rest/projects/{head}")

And use @PathVariable("head") instead of @RequestParam(name = "head")

For Javascript part, you should specify the head in the url :

function loadProjects(head) {
    $.ajax({
        url : 'rest/projects/' + head,
        method : 'GET',
        headers : {
            'Content-Type' : 'application/json',
        },
        success: function(data){
            $.each(data, function(index, project) {
                addProject(project);
            });
        }
    });
}