9. Build Get Employee By ID REST API

EmployeeService

    EmployeeDto getEmployeeById(Long employeeId);

EmployeeServiceImpl

    @Override
    public EmployeeDto getEmployeeById(Long employeeId) {
        Employee employee = employeeRepository.findById(employeeId).get();
        return EmployeeConverter.mapToEmployeeDto(employee);
    }

EmployeeController

    // build get employee by id REST API
    // http://localhost:8080/api/employees/1
    @GetMapping("{id}")
    public ResponseEntity<EmployeeDto> getEmployeeById(@PathVariable("id") Long employeeId){
        EmployeeDto employee = employeeService.getEmployeeById(employeeId);
        //return new ResponseEntity<>(employee, HttpStatus.OK);
        return ResponseEntity.ok(employee);
    }