pętla w main, kurs 0 dla błędnych kodów walut

src/main/java/Main.java

@@ -1,6 +1,23 @@
+import java.util.Scanner;
+
 public class Main {
     public static void main(String[] args) {
         EcbApi getRates = new EcbApi();
-        System.out.println(getRates.exchangeRate("PLN"));
+
+        String continuteInput;
+        Scanner read = new Scanner(System.in);
+
+        while(true) {
+            System.out.print("Podaj trzyliterowy kod waluty: ");
+            String currencyCode = read.nextLine();
+
+            System.out.println("Kurs EUR/" + currencyCode + " wynosi " + getRates.exchangeRate(currencyCode));
+
+            System.out.print("Czy chcesz sprawdzić kurs kolejnej waluty? [t/n] ");
+            continuteInput = read.nextLine();
+            if(continuteInput.equals("n")) {
+                break;
+            }
+        }
     }
 }

src/main/java/RatesProcessing.java

@@ -30,6 +30,11 @@ public class RatesProcessing {
     }
 
     public BigDecimal getRate(String currencyCode) {
-        return rates.get(currencyCode);
+        if(rates.containsKey(currencyCode)) {
+            return rates.get(currencyCode);
+        }
+        else {
+            return BigDecimal.valueOf(0);
+        }
     }
 }