BindingAlternativesApplicationTests.java

package actionjackson.alternative;

import com.fasterxml.jackson.core.JsonPointer;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.jayway.jsonpath.JsonPath;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.web.client.RestTemplate;

import java.util.List;
import java.util.Map;

@SpringBootTest
class BindingAlternativesApplicationTests {

	@Autowired RestTemplate restTemplate;

	@Test
	void mapToRequest() {
		var request =
				Map.of("key1", "value1",
					   "key2", Map.of(
							"nested", List.of("value2", "value3")));

		System.out.println(restTemplate.postForEntity("https://httpbin.org/post", request, String.class));
	}



	@Test
	void wrapRequest() {
		Conference springIo = new Conference("Spring I/O");
		System.out.println(restTemplate.postForEntity(
				"https://httpbin.org/post", Map.of("conference", springIo), String.class));
	}

	record Conference(String name) { }









	@Test
	void responseToMap() {
		Map<String, Object> response = restTemplate.getForObject("https://httpbin.org/get", Map.class);
		System.out.println("response = " + response);
		System.out.println("User-Agent: " + ((Map<String, Object>) response.get("headers")).get("User-Agent"));
	}












	@Test
	void responseToNodeWithJsonPointer() {
		JsonNode response = restTemplate.getForObject("https://httpbin.org/get", JsonNode.class);

		// Note: this should be a static final field in production code
		JsonPointer headersPointer = JsonPointer.compile("/headers/User-Agent");
		String agent = response.at(headersPointer).asText();
		System.out.println("agent from pointer = " + agent);
	}










	@Test
	void responseToNodeWithJsonPath() {
		JsonNode response = restTemplate.getForObject("https://httpbin.org/get", JsonNode.class);

		// Note: this should be a static final field in production code
		JsonPath jsonPath = JsonPath.compile("$..User-Agent");
		// to have this as returned type, you need the custom config from the main class!!!
		ArrayNode array = jsonPath.read(response);
		System.out.println("agent from path = " + array.get(0).asText());
	}



}