In Spring HATEOAS we can easily build links pointing to controller methods by using ControllerLinkBuilder#methodOn() . This method returns a proxy of the controller which records the last invocation of the method to build the links.
Example
Resource Object
public class Employee extends ResourceSupport {
private long employeeId;
private String name;
private String dept;
private int salary;
.............
}
Controller
@RestController
@RequestMapping("/employees")
public class EmployeeController {
@GetMapping(value = "/{employeeId}")
public Employee getEmployeeById(@PathVariable long employeeId) {
EmployeeController theController = ControllerLinkBuilder.methodOn(EmployeeController.class);
Employee employeeById = theController.getEmployeeById(employeeId);
Link selfLink = ControllerLinkBuilder.linkTo(employeeById).withSelfRel();
Employee employee = getEmployee(employeeId);
employee.add(selfLink);
return employee;
}
private Employee getEmployee(long employeeId) {
//todo: replace with employee service
return Employee.create(employeeId, "Lara", "Admin", 3000);
}
}
Running example
To try examples, run embedded tomcat (configured in pom.xml of example project below):
mvn tomcat7:run-war
Output
Accessing http://localhost:8080/employees/1 in a web browser will render:
{
"employeeId": 1,
"name": "Lara",
"dept": "Admin",
"salary": 3000,
"links": [
{
"rel": "self",
"href": "http://localhost:8080/employees/1",
"hreflang": null,
"media": null,
"title": null,
"type": null,
"deprecation": null
}
]}
Example ProjectDependencies and Technologies Used: - spring-hateoas 0.24.0.RELEASE:
Library to support implementing representations for
hyper-text driven REST web services.
Uses org.springframework:spring-web-mvc version 4.3.12.RELEASE - jackson-databind 2.9.5: General data-binding functionality for Jackson: works on core streaming API.
- javax.servlet-api 3.0.1 Java Servlet API
- JDK 10
- Maven 3.5.4
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