dorobić pętlę pytającą o waluty

ZJJX-Projekt2.iml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4" />

pom.xml

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>ZJJX-Projekt2</groupId>
+    <artifactId>ZJJX-Projekt2</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <dependencies>
+        <dependency>
+            <groupId>javax.json</groupId>
+            <artifactId>javax.json-api</artifactId>
+            <version>1.1.4</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish</groupId>
+            <artifactId>javax.json</artifactId>
+            <version>1.1</version>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+
+</project>

src/main/java/ApiException.java

@@ -0,0 +1,9 @@
+public class ApiException extends RuntimeException {
+    public ApiException(Throwable cause) {
+        super(cause);
+    }
+
+    public ApiException(String message) {
+        super(message);
+    }
+}

src/main/java/ConnectionFactory.java

@@ -0,0 +1,5 @@
+public class ConnectionFactory {
+    public HttpConnection build(String url) {
+        return new HttpConnection(url);
+    }
+}

src/main/java/EcbApi.java

@@ -0,0 +1,29 @@
+import javax.json.Json;
+import javax.json.JsonObject;
+import java.math.BigDecimal;
+
+public class EcbApi implements ExchangeApi {
+
+    private static final String API_URL_TEMPLATE = "https://api.exchangeratesapi.io/latest";
+
+    private final ConnectionFactory connectionFactory;
+    private final JsonObject json;
+
+    public EcbApi() {
+        this(new ConnectionFactory(), Json.createObjectBuilder().build());
+    }
+
+    public EcbApi(ConnectionFactory connectionFactory, JsonObject json) {
+        this.connectionFactory = connectionFactory;
+        this.json = json;
+    }
+
+    @Override
+    public BigDecimal exchangeRate(String currencyCode) {
+        try (HttpConnection connection = connectionFactory.build(API_URL_TEMPLATE)) {
+            String response = connection.response();
+            RatesProcessing rates = new RatesProcessing(response, currencyCode);
+            return rates.getRate(currencyCode);
+        }
+    }
+}

src/main/java/ExchangeApi.java

@@ -0,0 +1,5 @@
+import java.math.BigDecimal;
+
+public interface ExchangeApi {
+    BigDecimal exchangeRate(String currencyCode);
+}

src/main/java/HttpConnection.java

@@ -0,0 +1,51 @@
+import java.io.BufferedReader;
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+public class HttpConnection implements Closeable {
+
+    private final HttpURLConnection connection;
+
+    HttpConnection(String url) {
+        try {
+            connection = (HttpURLConnection) new URL(url).openConnection();
+        } catch (IOException e) {
+            throw new ApiException(e);
+        }
+    }
+
+    String response() {
+        validateResponse();
+        StringBuilder response = new StringBuilder();
+        try (BufferedReader responseReader = new BufferedReader(new InputStreamReader(connection.getInputStream()))) {
+            String line;
+            while ((line = responseReader.readLine()) != null) {
+                response.append(line);
+            }
+        } catch (IOException e) {
+            throw new ApiException(e);
+        }
+        return response.toString();
+    }
+
+    @Override
+    public void close() {
+        connection.disconnect();
+    }
+
+    void validateResponse() {
+        try {
+            int responseCode = connection.getResponseCode();
+            if (responseCode != 200) {
+                String responseMessage = connection.getResponseMessage();
+                throw new ApiException(String.format("Something went wrong! [%d] %s", responseCode, responseMessage));
+            }
+        } catch (IOException e) {
+            throw new ApiException(e);
+        }
+    }
+
+}

src/main/java/Main.java

@@ -0,0 +1,6 @@
+public class Main {
+    public static void main(String[] args) {
+        EcbApi getRates = new EcbApi();
+        System.out.println(getRates.exchangeRate("PLN"));
+    }
+}

src/main/java/RatesProcessing.java

@@ -0,0 +1,35 @@
+import javax.json.Json;
+import javax.json.stream.JsonParser;
+import java.io.StringReader;
+import java.math.BigDecimal;
+import java.util.HashMap;
+import java.util.Map;
+
+public class RatesProcessing {
+    private Map<String, BigDecimal> rates;
+
+    public RatesProcessing(String result, String currencyCode) {
+        this.rates = new HashMap<>();
+
+        final JsonParser parser = Json.createParser(new StringReader(result));
+        String key = null;
+        BigDecimal value = null;
+        while (parser.hasNext()) {
+            final JsonParser.Event event = parser.next();
+            switch (event) {
+                case KEY_NAME:
+                    key = parser.getString();
+                    break;
+                case VALUE_NUMBER:
+                    value = parser.getBigDecimal();
+                    break;
+            }
+            rates.put(key, value);
+        }
+        parser.close();
+    }
+
+    public BigDecimal getRate(String currencyCode) {
+        return rates.get(currencyCode);
+    }
+}