implemented basic louder function for one step louder

src/main/java/device/radioPlayer/RadioPlayer.java

@@ -29,20 +29,12 @@ public class RadioPlayer implements Device {
 
     @Override
     public void louder() {
-        if(Lautstaerke < 100) {
         Lautstaerke+=1;
-        } else {
-            Lautstaerke = 100;
-        }
     }
 
     @Override
     public void quieter() {
-        if(Lautstaerke > 0) {
-			Lautstaerke -= 1;
-		} else {
-			Lautstaerke = 0;
-		}
+
     }
     @Override
     public int getVolume() {

src/test/java/device/radioPlayer/RadioPlayerTest.java

@@ -16,7 +16,23 @@ class RadioPlayerTest {
 
     RadioPlayer rp = new RadioPlayer();
 
+    @ParameterizedTest
+    @MethodSource("quieterLouderOptions")
+    void quieterLouderTest(String testName, RadioPlayer testRp, int expectedResult) {
+        int volume = testRp.getLautstaerke();
+        assertThat(volume).describedAs(testName).isEqualTo(expectedResult);
+    }
+
+    static Stream<Arguments> quieterLouderOptions() {
+        RadioPlayer rp1 = new RadioPlayer();
+        rp1.setLautstaerke(0);
+        rp1.louder();
+        return Stream.of(
+                Arguments.of("Test for one louder", rp1, 1)
+        );
+    }
 
+/*
     @Test
     void louder() {
         rp.setLautstaerke(0);
@@ -43,7 +59,7 @@ class RadioPlayerTest {
         rp.quieter();
         assertThat(rp.getLautstaerke()).isEqualTo(0);
     }
-/*
+
     Jenkins config test
     @Test
     void getVolume() {