diff --git a/SimpleActivityStack/src/testat/ASimpleStackTestBase.java b/SimpleActivityStack/src/testat/ASimpleStackTestBase.java
new file mode 100644
index 0000000..892c950
--- /dev/null
+++ b/SimpleActivityStack/src/testat/ASimpleStackTestBase.java
@@ -0,0 +1,289 @@
+package testat;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.EmptyStackException;
+import java.util.Set;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/**
+ * 
+ * @author Christian
+ *
+ */
+public abstract class ASimpleStackTestBase<T> {
+
+	protected ISimpleStack<T> sstack;
+	protected boolean temp1 = false, temp2=true;
+
+	protected abstract ISimpleStack<T> getInstance();
+	protected IAction<T> act1, act2;
+	
+	protected T s1;
+	protected T s2;
+	protected T s3;
+	protected T s4;
+	protected T s5;
+	protected T s6;
+	protected T s7;
+	protected T s8;
+	protected T s9;
+	protected T s10;
+	
+	abstract protected void init() ;
+
+	@BeforeAll
+	static void setUpBeforeClass() throws Exception {
+
+	}
+
+	@BeforeEach
+	void setUp() throws Exception {
+		init();
+		sstack = getInstance();
+	}
+
+	@Test
+	public void testPush_1_Null() {
+		assertEquals(0, sstack.push(null));
+	}
+
+	@Test
+	public void testPush_2_Single() {
+		assertEquals(1, sstack.push(s1));
+	}
+
+	@Test
+	public void testPush_3_Multiple() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+		sstack.push(s6);
+		sstack.push(s7);
+
+		assertEquals(8, sstack.push(s8));
+	}
+
+	@Test
+	public void testSize_1_Initial() {
+		assertEquals(0, sstack.size());
+	}
+
+	@Test
+	public void testSize_2_AfterPush() {
+		sstack.push(s1);
+		assertEquals(1, sstack.size());
+	}
+
+	@Test
+	public void testSize_3_AfterPushs() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+
+		assertEquals(5, sstack.size());
+	}
+
+	@Test
+	public void testGet_1_Simple() {
+		sstack.push(s1);
+		assertEquals(s1, sstack.get(0));
+	}
+
+	@Test
+	public void testGet_2_Multiple() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+
+		assertEquals(s3, sstack.get(2));
+	}
+
+	@Test
+	public void testGet_3_ErrorHandling_1() {
+		sstack.push(s1);
+		sstack.push(s2);
+		try {
+			sstack.get(-1);
+		} catch (Exception e) {
+			assertEquals(true, e instanceof IndexOutOfBoundsException);
+			assertEquals(false, e instanceof EmptyStackException);
+		} finally {
+			assertEquals(2, sstack.size());
+		}
+
+	}
+
+	@Test
+	public void testGet_4_ErrorHandling_2() {
+		sstack.push(s1);
+		sstack.push(s2);
+		try {
+			sstack.get(5);
+		} catch (Exception e) {
+			assertEquals(true, e instanceof IndexOutOfBoundsException);
+		} finally {
+			assertEquals(2, sstack.size());
+		}
+	}
+
+	@Test
+	public void testPop_1_Initial() {
+		assertEquals(null, sstack.pop());
+	}
+
+	@Test
+	public void testPop_2_Single() {
+		sstack.push(s1);
+		assertEquals(s1, sstack.pop());
+	}
+
+	@Test
+	public void testPop_3_Multiple() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+		assertEquals(s5, sstack.pop());
+		assertEquals(s4, sstack.pop());
+		assertEquals(s3, sstack.pop());
+	}
+
+	@Test
+	public void testPush_4_Existing() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+		sstack.push(s2);
+
+		assertEquals(s2, sstack.pop());
+	}
+
+	@Test
+	public void testPush_5_AfterPop() {
+		// TODO Test Push after Pop
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+		sstack.pop();
+		sstack.push(s7);
+
+		assertEquals(6, sstack.push(s8));
+	}
+
+	@Test
+	public void testGet_5_AfterPop() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+		sstack.pop();
+		sstack.pop();
+		sstack.pop();
+		sstack.push(s6);
+		sstack.push(s7);
+
+		assertEquals(s6, sstack.get(2));
+	}
+
+	@Test
+	public void testRemove_1_One() {
+		sstack.push(s1);
+		assertEquals(s1, sstack.remove(0));
+	}
+
+	@Test
+	public void testRemove_2_Index() {
+		sstack.push(s1);
+		sstack.push(s2);
+
+		try {
+			sstack.remove(-1);
+		} catch (Exception e) {
+			assertEquals(true, e instanceof IndexOutOfBoundsException);
+		} finally {
+			assertEquals(2, sstack.size());
+		}
+
+		try {
+			sstack.remove(5);
+		} catch (Exception e) {
+			assertEquals(true, e instanceof IndexOutOfBoundsException);
+		} finally {
+			assertEquals(2, sstack.size());
+		}
+
+	}
+
+	@Test
+	public void testRemove_4_Multiple() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.push(s4);
+		sstack.push(s5);
+
+		assertEquals(s3, sstack.remove(2));
+		assertEquals(4, sstack.size());
+	}
+
+	@Test
+	public void testContains_1() {
+		assertEquals(false, sstack.contains(s2));
+
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+
+		assertEquals(false, sstack.contains(s4));
+		assertEquals(true, sstack.contains(s2));
+
+		assertEquals(true, sstack.contains(s3));
+		assertEquals(s3, sstack.pop());
+		assertEquals(false, sstack.contains(s3));
+	}
+	
+	@Test
+	public void testForAll_1() {
+		assertEquals(false, temp1);
+		assertEquals(true, temp2);
+
+		this.sstack.forAll(act1);
+		this.sstack.forAll(act2);
+
+		assertEquals(true, temp1);
+		assertEquals(true, temp2);
+	}
+
+	@Test
+	public void testSize_4_AfterRemove_1() {
+		sstack.push(s1);
+		sstack.pop();
+		assertEquals(0, sstack.size());
+	}
+
+	@Test
+	public void testSize_4_AfterRemove_2() {
+		sstack.push(s1);
+		sstack.push(s2);
+		sstack.push(s3);
+		sstack.pop();
+		assertEquals(2, sstack.size());
+	}
+
+}