I am new to java HttpClient and am currently trying to create a RestServiceApplication, but i am unable to convert a HttpResponse to a String array in order to access the elements of the array.
package com.example.restservice;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class RestServiceApplication {
public static void main(String[] args) {
SpringApplication.run(RestServiceApplication.class, args);
}
}
I have implemented the following controller for the application which has different methods that each return an array of String.
package com.example.restservice;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class ConfigurationController {
@GetMapping("/getlenkertypen")
public String[] getLenkertypen() {
String[] lenker = new String[3];
lenker[0] = "Flatbarlenker";
lenker[1] = "Rennradlenker";
lenker[2] = "Bullhornlenker";
return lenker;
}
@GetMapping("/getmaterial")
public String[] getMaterial() {
String[] material = new String[3];
material[0] = "Aluminium";
material[1] = "Stahl";
material[2] = "Kunststoff";
return material;
}
@GetMapping("/getschaltung")
public String[] getSchaltung() {
String[] schaltung = new String[3];
schaltung[0] = "Kettenschaltung";
schaltung[1] = "Nabenschaltung";
schaltung[2] = "Tretlagerschaltung";
return schaltung;
}
@GetMapping("/getgriff")
public String[] getGriff() {
String[] griff = new String[3];
griff[0] = "Ledergriff";
griff[1] = "Schaumstoffgriff";
griff[2] = "Kunststoffgriff";
return griff;
}
@GetMapping("/test")
public String test() {
String[] griff = new String[3];
griff[0] = "Ledergriff";
griff[1] = "Schaumstoffgriff";
griff[2] = "Kunststoffgriff";
return "test";
}
}
Now i want the HttpClient to request those methods and access the Strings of the array.
My problem is that the returned String[] arrays are not arrays but a single String (BodyHandler.ofString()), so i cannot access the elements anymore. I hoped to solve this with the BodyHander.ofLine()-method, converting the response to a Stream and then call the toArray() function on the stream. But it is still creating an array that has only one element, containing the same String i get from the ofString()-method. Here is my client:
package com.example.restservice;
import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.Scanner;
import java.util.stream.Stream;
public class GetRequest {
public static void main(String[] args) throws IOException, InterruptedException {
HttpClient client = HttpClient.newHttpClient();
/*
* Abfrage Lenkertypen
*/
HttpRequest requestLenkertypen = HttpRequest.newBuilder()
.uri(URI.create("http://localhost:8081/getlenkertypen"))
.build();
HttpResponse<Stream<String>> lenkerResponse = client.send(requestLenkertypen,
HttpResponse.BodyHandlers.ofLines());
String[] lenkerArray = lenkerResponse.body().toArray(String[]::new);
System.out.println("Bitte wählen Sie als erstes den Lenker aus: ");
for (int i = 0; i < lenkerArray.length; i++) {
System.out.println(lenkerArray[i] + " " + i);
}
System.out.println(lenkerArray[0]);
Scanner scanner = new Scanner(System.in);
int answer = scanner.nextInt();
System.out.println(answer);
HttpRequest requestSchaltung = HttpRequest.newBuilder()
.uri(URI.create("http://localhost:8081/getschaltung"))
.build();
HttpResponse<String> response = client.send(requestSchaltung,
HttpResponse.BodyHandlers.ofString());
System.out.println(response.body());
}
}
By googling i found out that i somehow need to parse the response JSON, but i do not know how. I downloaded the project structure from spring.io so i think the response returns as JSON, but i am new to this and any help would be appreaciated.
Thanks!
