failure: class Course was not abstract

added examples for LabCourse and Webinar instantiation

src/java_exercises3_1_1/Course.java

@@ -6,7 +6,7 @@ package java_exercises3_1_1;
  * @author mad
  *
  */
-public class Course {
+public abstract class Course {
 	private String name;
 	private int id;
 	

src/java_exercises3_1_1/TestUni.java

 package java_exercises3_1_1;
 
+import java.net.MalformedURLException;
+import java.net.URL;
+
 import java_exercises3_1_1.*;
 
 /**
@@ -8,7 +11,7 @@ import java_exercises3_1_1.*;
  *
  */
 public class TestUni {
-	public static void main(String[] args) {
+	public static void main(String[] args) throws MalformedURLException {
 		//Instantiate student called Martin
 		Student student=new Student("Martin",1);
 		University uni=new University();
@@ -16,18 +19,27 @@ public class TestUni {
 		uni.register(student);
 		
 		//Book Student Martin for the course Java Intro
-		Course course=new Course("Java Intro",1);
+		Course labCourse=new LabCourse("Java Intro",1, new String[]{"Exercise 1","Exercise 2"});
 		//From here we can't access the member variables of class Course because they are private.
 		//Let's try to book the course by a Student.
-		course.book(student);
+		labCourse.book(student);
 		
 		//Book Alumni Peter for course Java Intro
 		Alumni alumni=new Alumni("Peter");
 		//Also alumnis are allowed to book a course.
-		course.book(alumni);
+		labCourse.book(alumni);
 		//But alumnis are not allowed to register. If you uncomment the follwing line you will get a compile error.
 		//uni.register(alumni);
 		
+		Course webinar=new Webinar("Java for Embedded",2,new URL("http://es.technikum-wien.at/webinar/"));
+		webinar.book(student);
+		webinar.book(alumni);
+		
+		//Existent courses
+		System.out.println("\nThe following courses exist:");
+		System.out.println(labCourse);
+		System.out.println(webinar+"\n");
+		
 		//Both alumnis and students implement the Attendee interface and hence provide a method called getName.
 		System.out.println("Name of Student: "+student.getName()+", Name of Alumni: "+alumni.getName());