https://github.com/spring-projects/spring-framework: Spring Web (Spring IO)
  • Juergen Hoeller 
Core package of the client-side web support.
Provides a RestTemplate class and various callback interfaces.

/**
 * Core package of the client-side web support.
 * Provides a RestTemplate class and various callback interfaces.
 */
@NonNullApi
@NonNullFields
package org.springframework.web.client;

import org.springframework.lang.NonNullApi;
import org.springframework.lang.NonNullFields;