EK HI RESOURCE, MULTIPLE FORMATS mein, REPRESENT ho sakta hai — DEFAULT mein, Spring Boot, JSON RETURN karta hai (Jackson library SE). AGAR jackson-dataformat-xml DEPENDENCY, ADD ki jaaye, SAME CONTROLLER, CLIENT ke Accept HEADER ke BASIS PAR, XML bhi, RETURN kar sakta hai — CODE mein, KOI CHANGE NAHI CHAHIYE.

PRACTICALLY, MODERN, PUBLIC-FACING REST APIs, LAGBHAG HAMESHA, SIRF JSON SUPPORT karte hain — XML SUPPORT, TYPICALLY, LEGACY SYSTEMS ke SAATH, INTEGRATION ke liye, ZAROORI PADТA hai.

<!-- XML support enable karne ke liye: -->
<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-xml</artifactId>
</dependency>

// Controller code, BILKUL SAME rehta hai:
@GetMapping("/{id}")
public Product getProduct(@PathVariable Long id) { return productService.findById(id); }

// Client ke Accept header ke basis par:
// Accept: application/json → JSON response
// Accept: application/xml  → XML response (agar dependency added hai)