implemented Lautstraerke & function louder for RadioPlayer + AssertJ test for louder

src/main/java/device/CDPlayer.java

@@ -5,7 +5,7 @@ public class CDPlayer implements Device {
     public void louder() {
 
     }
-
+/*
     @Override
     public void quieter() {
 
@@ -45,4 +45,6 @@ public class CDPlayer implements Device {
     public String play() {
         return null;
     }
+
+ */
 }

src/main/java/device/Device.java

@@ -3,7 +3,10 @@ package device;
 public interface Device {
 
 	void louder();
+	/*
 	void quieter();
+
+	void quiter();
 	int getVolume();
 	void next();
 	void prev();
@@ -11,4 +14,6 @@ public interface Device {
 	String[] getOptions();
 	void chooseOption(String opt);
 	String play();
+
+	 */
 	}

src/main/java/device/RadioPlayer.java

@@ -1,11 +1,25 @@
 package device;
 
 public class RadioPlayer implements Device {
-    @Override
-    public void louder() {
 
+    public void setLautstaerke(int lautstaerke) {
+        Lautstaerke = lautstaerke;
+    }
+
+    public int getLautstaerke() {
+        return Lautstaerke;
     }
 
+    int Lautstaerke = 0;
+    @Override
+    public void louder() {
+        if(Lautstaerke < 100) {
+            Lautstaerke += 1;
+        } else {
+            Lautstaerke = 100;
+        }
+    }
+    /*
     @Override
     public void quieter() {
 
@@ -45,4 +59,6 @@ public class RadioPlayer implements Device {
     public String play() {
         return null;
     }
+
+     */
 }

src/main/java/device/UsbPlayer.java

@@ -6,7 +6,7 @@ public class UsbPlayer implements Device{
     public void louder() {
 
     }
-
+/*
     @Override
     public void quieter() {
 
@@ -46,4 +46,6 @@ public class UsbPlayer implements Device{
     public String play() {
         return null;
     }
+
+ */
 }

src/test/java/device/RadioPlayerTest.java

@@ -1,17 +1,39 @@
 package device;
 
+import org.junit.Before;
 import org.junit.jupiter.api.Test;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.*;
 
 class RadioPlayerTest {
 
+    RadioPlayer rp = new RadioPlayer();
+
+    @Before
+    void setup()
+    {
+        rp.setLautstaerke(0);
+    }
     @Test
     void louder() {
+        rp.louder();
+        assertThat(rp.getLautstaerke()).isEqualTo(1);
+    }
+
+    @Before
+    void setup1()
+    {
+        rp.setLautstaerke(100);
     }
 
     @Test
-    void quiter() {
+    void loudermax() {
+
+    }
+/*
+    @Test
+    void quieter() {
     }
 
     @Test
@@ -41,4 +63,6 @@ class RadioPlayerTest {
     @Test
     void play() {
     }
+
+ */
 }