findById

Service

public ProductDTO findById(UUID id) {
    Product entity = repository.findById(id)
            .orElseThrow(() -> new ResourceNotFoundException("Department not found"));

    return new ProductDTO(entity);
}

Controller

@GetMapping(value = "/{id}")
public ResponseEntity<ProductDTO> findById(@PathVariable UUID id) {
    ProductDTO dto = productService.findById(id);
    return ResponseEntity.ok().body(dto);
}