Przykłady używające Jakarta JSON

PC36-RestKlient/pom.xml

@@ -12,4 +12,22 @@
 		<maven.compiler.source>17</maven.compiler.source>
 	</properties>
 
-</project>
+	<dependencies>
\ No newline at end of file
+		<!-- implementacje technologii Jakarta JSON P
+		     - Glassfish to starsza wersja,
+		     - Eclipse Parsson to nowsza -->
+		<!--
+                <dependency>
+                    <groupId>org.glassfish</groupId>
+                    <artifactId>jakarta.json</artifactId>
+                    <version>2.0.1</version>
+                </dependency>
+                -->
+		<dependency>
+			<groupId>org.eclipse.parsson</groupId>
+			<artifactId>parsson</artifactId>
+			<version>1.1.4</version>
+		</dependency>
+	</dependencies>
+
+</project>

PC36-RestKlient/src/main/java/rest_klient/Klient02_URL_JSON.java

+package rest_klient;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+
+import jakarta.json.Json;
+import jakarta.json.JsonArray;
+import jakarta.json.JsonReader;
+import jakarta.json.JsonValue;
+
+public class Klient02_URL_JSON {
+
+	public static void main(String[] args) {
+		try {
+			URL url = new URL(Ustawienia.ADRES_USLUGI + "/products.json");
+			try(InputStream inputStream = url.openStream();
+				JsonReader reader = Json.createReader(inputStream)) {
+				JsonArray array = reader.readArray();
+				// System.out.println(array);
+				for(JsonValue jsonValue : array) {
+					//System.out.println(jsonValue);
+					System.out.println(jsonValue.asJsonObject().getString("productName"));
+					System.out.println("    opis: " + jsonValue.asJsonObject().getString("description", ""));
+					System.out.println("    cena: " + jsonValue.asJsonObject().getJsonNumber("price").bigDecimalValue());
+				}
+			}
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+}

PC36-RestKlient/src/main/java/rest_klient/Klient05_HttpClient_Accept.java

+package rest_klient;
+
+import java.io.IOException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.HttpResponse.BodyHandlers;
+
+public class Klient05_HttpClient_Accept {
+
+    public static void main(String[] args) {
+        HttpClient httpClient = HttpClient.newHttpClient();
+        try {
+            URI uri = new URI(Ustawienia.ADRES_USLUGI + "/products");
+            // W tej wersji do zapytania dodajemy nagłówek Accept
+            HttpRequest request = HttpRequest.newBuilder(uri)
+            		.header("Accept", "text/plain")
+            		.build();
+            HttpResponse<String> response = httpClient.send(request, BodyHandlers.ofString());
+            System.out.println("response " + response);
+            System.out.println("status: " + response.statusCode());
+            System.out.println("Content-Type: " + response.headers().firstValue("Content-Type").orElse("BRAK"));
+            System.out.println("Treść odpowiedzi:\n" + response.body());
+        } catch (URISyntaxException | IOException | InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+
+}

PC36-RestKlient/src/main/java/rest_klient/Klient06_HttpClient_JSON.java

+package rest_klient;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.math.BigDecimal;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.HttpResponse.BodyHandlers;
+
+import jakarta.json.Json;
+import jakarta.json.JsonObject;
+import jakarta.json.JsonReader;
+
+public class Klient06_HttpClient_JSON {
+	/* W tej wersji używamy technologii Jakarta JSON P.
+	 * 
+	 * Widzimy drzewo danych jsonowych i jego elementytakie jak JsonObject, JsonArray, ...
+	 * Mamy dostęp do poszczególnych pól.
+	 */
+
+    public static void main(String[] args) {
+        HttpClient httpClient = HttpClient.newHttpClient();
+        try {
+            URI uri = new URI(Ustawienia.ADRES_USLUGI + "/products/1");
+            HttpRequest request = HttpRequest.newBuilder(uri)
+            		.header("Accept", "application/json")
+            		.build();
+            HttpResponse<InputStream> response = httpClient.send(request, BodyHandlers.ofInputStream());
+            System.out.println("response " + response);
+            System.out.println("status: " + response.statusCode());
+            System.out.println("Content-Type: " + response.headers().firstValue("Content-Type").orElse("BRAK"));
+            
+            JsonReader reader = Json.createReader(response.body());
+            JsonObject product = reader.readObject();
+            System.out.println("Pobrany obiekt jsonowy: " + product);
+            String nazwa = product.getString("productName");
+            String opis = product.getString("description", "BRAK OPISU");
+            BigDecimal cena = product.getJsonNumber("price").bigDecimalValue();
+            System.out.println(nazwa + " za cenę " + cena + " , opis: " + opis);
+            reader.close();
+        } catch (URISyntaxException | IOException | InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+
+}

PC36-RestKlient/src/main/java/rest_klient/Klient07_HttpClient_JSON_Lista.java

+package rest_klient;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.HttpResponse.BodyHandlers;
+
+import jakarta.json.Json;
+import jakarta.json.JsonArray;
+import jakarta.json.JsonObject;
+import jakarta.json.JsonReader;
+import jakarta.json.JsonValue;
+
+public class Klient07_HttpClient_JSON_Lista {
+
+    public static void main(String[] args) {
+        try {
+            JsonArray array = pobierzJsona(Ustawienia.ADRES_USLUGI + "/products.json");
+            for(JsonValue jsonValue : array) {
+                JsonObject jsonObject = jsonValue.asJsonObject();
+                System.out.println(jsonObject.getString("productName"));
+                if(jsonObject.containsKey("description")) {
+                    System.out.println("    opis: " + jsonObject.getString("description", ""));
+                }
+                System.out.println("    cena: " + jsonObject.getJsonNumber("price").bigDecimalValue());
+            }
+        } catch (IOException | InterruptedException | URISyntaxException e) {
+            e.printStackTrace();
+        }
+    }
+
+    private static JsonArray pobierzJsona(String adres) throws IOException, InterruptedException, URISyntaxException {
+        HttpClient httpClient = HttpClient.newHttpClient();
+        URI uri = new URI(adres);
+        HttpRequest request = HttpRequest.newBuilder(uri).build();
+        HttpResponse<InputStream> response = httpClient.send(request, BodyHandlers.ofInputStream());
+        System.out.println("response " + response);
+        System.out.println("status: " + response.statusCode());
+        System.out.println("Content-Type: " + response.headers().firstValue("Content-Type").orElse("BRAK"));
+        return wczytajJsona(response.body());
+    }
+
+    private static JsonArray wczytajJsona(InputStream input) {
+        try(JsonReader reader = Json.createReader(input)) {
+            return reader.readArray();
+        }
+    }
+
+}