OkHttp vs Retrofit: What are the differences?

OkHttp and Retrofit are two popular libraries used for making HTTP requests in Android applications. Let's explore the key differences between them.

1. Integration: OkHttp is a lower-level HTTP client that provides a simple API to send HTTP requests and receive responses. It can be seamlessly integrated into any Android project. Retrofit, on the other hand, is a higher-level library built on top of OkHttp that simplifies the process of sending HTTP requests by providing a rich set of annotations and converters.

2. Annotation-based approach: Retrofit uses annotations to define the structure of the API endpoints and map them to the corresponding HTTP requests. This allows for a more declarative approach, making it easier to define API interfaces without the need to explicitly write code for each request. OkHttp, being a lower-level library, does not provide this annotation-based approach and requires manual coding for each request.

3. Response parsing: Retrofit simplifies the process of parsing HTTP responses by allowing the developer to define converters that can convert the raw response data into Java objects using libraries like Gson or Jackson. OkHttp, on the other hand, does not offer this built-in response parsing mechanism and requires the developer to handle the raw response data manually.

4. Network interceptors: OkHttp provides a powerful feature called network interceptors, which allows intercepting and modifying outgoing requests and incoming responses. This can be useful for tasks like logging, authentication, or adding custom headers. Retrofit does not offer built-in support for network interceptors and relies on OkHttp for this functionality.

5. Ease of use: Retrofit simplifies the process of making HTTP requests by providing a high-level and intuitive API. It handles many common tasks such as URL encoding, query parameter injection, and form data submission, making it easier for developers to work with HTTP requests. OkHttp, being a lower-level library, requires more manual coding for these tasks.

6. Flexibility: OkHttp provides a lot of flexibility and customization options, allowing developers to fine-tune the behavior of HTTP requests and responses. It offers features like connection pooling, request/response caching, and automatic retries. Retrofit, while built on top of OkHttp, abstracts away some of these advanced features and provides a more opinionated and simplified interface.

In summary, OkHttp is a lower-level library that provides greater flexibility and customization options for HTTP requests, while Retrofit is a higher-level library that simplifies the process of making HTTP requests by offering annotation-based API interfaces and built-in response parsing capabilities.