Changeset 1146 for trunk/autoquest-test-utils

Timestamp:

04/04/13 16:06:07 (11 years ago)

Author:

pharms

Message:

• complete refactoring of task tree model with a separation of task models and task instances
• appropriate adaptation of task tree generation process
• appropriate adaptation of commands and task tree visualization

Location:

trunk/autoquest-test-utils/src/main/java/de/ugoe/cs/autoquest/tasktrees

Files:

• TaskTreeChecker.java (modified) (15 diffs)
• TaskTreeDecoder.java (moved) (moved from trunk/autoquest-test-utils/src/main/java/de/ugoe/cs/autoquest/tasktrees/TaskTreeInstantiator.java) (8 diffs)
• TaskTreeEncoder.java (added)
• TaskTreeValidator.java (added)

trunk/autoquest-test-utils/src/main/java/de/ugoe/cs/autoquest/tasktrees/TaskTreeChecker.java

@@ -17 +17 @@
 import static org.junit.Assert.*;
 
-import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
-import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -33 +30 @@
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ISelection;
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ISequence;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTree;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTreeNode;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTreeNodeInfo;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITask;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstance;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstanceList;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession;
 
 /**
@@ -56 +54 @@
 
     /**
-     * TODO: comment
-     * 
+     *
      */
     public TaskTreeChecker() {
@@ -64 +61 @@
 
     /**
-     * TODO: comment
-     * 
+     *
      */
     public TaskTreeChecker(boolean doTrace) {
@@ -74 +70 @@
      *
      */
-    public void assertTaskTree(String taskTreeSpec, ITaskTree taskTree) {
-        Map<ITaskTreeNode, Integer> taskMapCopy = new HashMap<ITaskTreeNode, Integer>();
-
-        for (Map.Entry<ITaskTreeNode, ITaskTreeNodeInfo> entry : taskTree.getTaskMap().entrySet()) {
-            if (entry.getValue().getNoOfOccurencesInTree() > 0) {
-                taskMapCopy.put(entry.getKey(), entry.getValue().getNoOfOccurencesInTree());
-            }
-            else {
-                taskMapCopy.put(entry.getKey(), 1);
-            }
-        }
-
+    public void assertTaskInstanceList(String userSessionSpec, ITaskInstanceList taskInstances) {
         if (doTrace) {
-            dumpTaskMap(taskMapCopy);
-        }
-
-        TaskSpec task = null;
-
-        Matcher taskMatcher = taskPattern.matcher(taskTreeSpec);
+            new TaskTreeEncoder().encode(taskInstances, System.err);
+        }
+
+        TaskSpec taskInstanceSpec = null;
+
+        Matcher taskMatcher = taskPattern.matcher(userSessionSpec);
+        
+        Map<String, ITask> tasks = new HashMap<String, ITask>();
 
         while (taskMatcher.find()) {
 
-            task = parseTask(taskMatcher);
-            
-            if (task != null) {
-                assertTaskAndChildrenInMapAndRemove(task, taskMapCopy);
-            }
-        }
-
-        assertTrue("more tasks in map, than expected", taskMapCopy.isEmpty());
-    }
-
-    /**
-     * <p>
-     * TODO: comment
-     * </p>
-     *
-     * @param oracle
-     * @param result
-     */
-    public void assertTaskNodesEqual(ITaskTreeNode expected, ITaskTreeNode checked) {
+            taskInstanceSpec = parseTaskInstance(taskMatcher);
+            
+            if (taskInstanceSpec != null) {
+                assertTaskInstanceList(taskInstanceSpec, taskInstances, tasks);
+            }
+        }
+    }
+
+    /**
+     *
+     */
+    public void assertTaskInstanceListsEqual(ITaskInstanceList expected, ITaskInstanceList checked)
+    {
         if (expected == null) {
             assertNull("null", checked);
@@ -123 +104 @@
             assertEquals(expected.toString() + ": types do not match",
                          expected.getClass(), checked.getClass());
-            assertEquals(expected.toString() + ": names do not match",
-                         expected.getName(), checked.getName());
-            
-            List<ITaskTreeNode> expectedChildren = expected.getChildren();
-            List<ITaskTreeNode> checkedChildren = checked.getChildren();
+            
+            if ((expected != null) && (expected.size() > 0)) {
+                assertNotNull(expected.toString() + ": children not there", checked);
+                assertEquals(expected.toString() + ": different number of children",
+                             expected.size(), checked.size());
+                
+                Map<ITask, ITask> equalTasksMap = new HashMap<ITask, ITask>();
+                for (int i = 0; i < expected.size(); i++) {
+                    assertTaskInstancesEqual(expected.get(i), checked.get(i), equalTasksMap);
+                }
+            }
+            else {
+                assertTrue(expected.toString() + ": unexpected children",
+                           (checked == null) || (checked.size() == 0));
+            }
+        }
+    }
+
+    /**
+     *
+     */
+    public void assertTaskInstancesEqual(ITaskInstance expected, ITaskInstance checked) {
+        Map<ITask, ITask> equalTasksMap = new HashMap<ITask, ITask>();
+        assertTaskInstancesEqual(expected, checked, equalTasksMap);
+    }
+
+    /**
+     *
+     */
+    private void assertTaskInstancesEqual(ITaskInstance     expected,
+                                          ITaskInstance     checked,
+                                          Map<ITask, ITask> equalTasksMap)
+    {
+        if (expected == null) {
+            assertNull("null", checked);
+        }
+        else {
+            assertNotNull(expected.toString(), checked);
+            
+            assertEquals(expected.toString() + ": types do not match",
+                         expected.getClass(), checked.getClass());
+            
+            if (equalTasksMap.containsKey(expected.getTask())) {
+                assertEquals(expected.toString() + ": tasks do not match",
+                             checked.getTask(), equalTasksMap.get(expected.getTask()));
+            }
+            else {
+                equalTasksMap.put(expected.getTask(), checked.getTask());
+            }
+            
+            List<ITaskInstance> expectedChildren = expected.getChildren();
+            List<ITaskInstance> checkedChildren = checked.getChildren();
             
             if ((expectedChildren != null) && (expectedChildren.size() > 0)) {
@@ -136 +164 @@
                 if (expected instanceof ISequence) {
                     for (int i = 0; i < expectedChildren.size(); i++) {
-                        assertTaskNodesEqual(expectedChildren.get(i), checkedChildren.get(i));
+                        assertTaskInstancesEqual(expectedChildren.get(i), checkedChildren.get(i));
                     }
                 }
@@ -144 +172 @@
                         for (int j = 0; j < checkedChildren.size(); j++) {
                             try {
-                                assertTaskNodesEqual
+                                assertTaskInstancesEqual
                                     (expectedChildren.get(i), checkedChildren.get(j));
                                 found = true;
@@ -166 +194 @@
 
     /**
-     * TODO: comment
      * 
-     * @param taskTree
-     */
-    public void dumpAsCheckString(ITaskTree taskTree) {
-        dumpNodeAsCheckString(taskTree.getRoot(), new int[4], "");
-    }
-
-    /**
-     * TODO: comment
-     * 
-     * @param root
-     * @param string
-     */
-    private void dumpNodeAsCheckString(ITaskTreeNode node, int[] typeCounters, String indent) {
-        System.out.print("       \"");
-        System.out.print(indent);
-
-        if (node instanceof ISequence) {
-            System.out.print("Sequence sequence");
-            System.out.print(typeCounters[0]++);
-            System.out.println(" {\" +");
-        }
-        else if (node instanceof IIteration) {
-            System.out.print("Iteration iteration");
-            System.out.print(typeCounters[1]++);
-            System.out.println(" {\" +");
-        }
-        else if (node instanceof ISelection) {
-            System.out.print("Selection selection");
-            System.out.print(typeCounters[2]++);
-            System.out.println(" {\" +");
-        }
-        else if (node instanceof IEventTask) {
-            if (((IEventTask) node).getEventType() instanceof TextInput) {
-                System.out.print("TextInputEvent textInput");
-                System.out.print(typeCounters[3]++);
-                System.out.print(" \"");
-                System.out.print(((TextInput) ((IEventTask) node).getEventType()).getEnteredText());
-                System.out.print("\"");
-            }
-            else {
-                System.out.print("Event ");
-                System.out.print(((IEventTask) node).getEventType().getName());
-            }
-            System.out.print(" {}\" +");
-        }
-        else {
-            fail("unknown type of node in task tree " + node);
-        }
-
-        for (ITaskTreeNode child : node.getChildren()) {
-            dumpNodeAsCheckString(child, typeCounters, indent + "  ");
-        }
-
-        if (!(node instanceof IEventTask)) {
-            System.out.print("       \"");
-            System.out.print(indent);
-            System.out.print("}\" +");
-        }
-
-        System.out.println();
-    }
-
-    /**
-     * TODO: comment
-     * 
-     * @param taskTree
-     */
-    public void dumpFullTaskTree(ITaskTree taskTree) throws FileNotFoundException {
-        PrintWriter out = null;
-        try {
-            out = new PrintWriter(new FileOutputStream("taskTree.txt"));
-            dumpFullNode(taskTree.getRoot(), out, "", 0);
-        }
-        finally {
-            if (out != null) {
-                out.close();
-            }
-        }
-
-    }
-
-    /**
-     *
-     */
-    private void dumpFullNode(ITaskTreeNode node, PrintWriter out, String indent, int index) {
-        if (node instanceof ISequence) {
-            if (index > 0) {
-                out.println();
-            }
-            out.print(indent);
-            out.print(node.toString());
-            out.println(" {");
-        }
-        else if (node instanceof IIteration) {
-            if (index > 0) {
-                out.println();
-            }
-            out.print(indent);
-            out.print(node.toString());
-            out.println(" {");
-        }
-        else if (node instanceof ISelection) {
-            if (index > 0) {
-                out.println();
-            }
-            out.print(indent);
-            out.print(node.toString());
-            out.println(" {");
-        }
-        else if (node instanceof IEventTask) {
-            out.print(indent);
-            out.print(((IEventTask) node).getEventType());
-            out.print(" ");
-            out.print(((IEventTask) node).getEventTarget().getStringIdentifier());
-//            if (((IEventTask) node).getEventTarget() instanceof IGUIElement) {
-//              out.print(" ");
-//              out.print(((IGUIElement) ((IEventTask) node).getEventTarget()).getSpecification());
-//            }
-        }
-        else {
-            fail("unknown type of node in task tree " + node);
-        }
-
-        int i = 0;
-        for (ITaskTreeNode child : node.getChildren()) {
-            dumpFullNode(child, out, indent + "  ", i++);
-        }
-
-        if (!(node instanceof IEventTask)) {
-            out.print(indent);
-            out.print("}");
-        }
-
-        out.println();
-    }
-
-    /**
-     * 
-     */
-    private TaskSpec parseTask(Matcher taskMatcher) {
+     */
+    private TaskSpec parseTaskInstance(Matcher taskMatcher) {
         if ("}".equals(taskMatcher.group(1))) {
             throw new IllegalArgumentException("invalid task specification");
@@ -338 +227 @@
         List<TaskSpec> children = new ArrayList<TaskSpec>();
         while (taskMatcher.find() && !"}".equals(taskMatcher.group(0))) {
-            children.add(parseTask(taskMatcher));
+            children.add(parseTaskInstance(taskMatcher));
         }
 
@@ -352 +241 @@
      * @param taskMapCopy
      */
-    private void assertTaskAndChildrenInMapAndRemove(TaskSpec                    task,
-                                                     Map<ITaskTreeNode, Integer> taskMap)
+    private void assertTaskInstanceList(TaskSpec           taskSpec,
+                                        ITaskInstanceList  taskInstances,
+                                        Map<String, ITask> tasks)
     {
-        for (Map.Entry<ITaskTreeNode, Integer> entry : taskMap.entrySet()) {
-            if (taskSpecEqualsTask(task, entry.getKey())) {
-                if (task.children != null) {
-                    for (TaskSpec child : task.children) {
-                        assertTaskAndChildrenInMapAndRemove(child, taskMap);
-                    }
-                }
-
-                int count = taskMap.get(entry.getKey());
-                if (count == 1) {
-                    taskMap.remove(entry.getKey());
-                }
-                else {
-                    taskMap.put(entry.getKey(), count - 1);
-                }
-                return;
-            }
-        }
-
-        fail("expected task " + task.type + " " + task.name + " not included in task map");
-    }
-
-    /**
-     *
-     */
-    private boolean taskSpecEqualsTask(TaskSpec taskSpec, ITaskTreeNode task) {
+        if (doTrace) {
+            System.err.println("\ncomparing " + taskSpec.type + " with " + taskInstances + "\n");
+        }
+
+        if ((taskInstances instanceof IUserSession) && (!"UserSession".equals(taskSpec.type))) {
+            fail("can not compare a task instance with a user session");
+        }
+        else if ((!(taskInstances instanceof IUserSession)) &&
+                 (!"TaskInstances".equals(taskSpec.type)))
+        {
+            fail("can not compare a task instance with a task instance list");
+        }
+        
+        if (taskSpec.children.length != taskInstances.size()) {
+            fail("number of task instances in task instance list does not match");
+        }
+        
+        for (int i = 0; i < taskInstances.size(); i++) {
+            TaskSpec childSpec = taskSpec.children[i];
+            assertTrue(taskSpecEqualsTaskInstance(childSpec, taskInstances.get(i), tasks));
+        }
+    }
+
+    /**
+     *
+     */
+    private boolean taskSpecEqualsTaskInstance(TaskSpec           taskSpec,
+                                               ITaskInstance      taskInstance,
+                                               Map<String, ITask> tasks)
+    {
         if (doTrace) {
             System.err.println("comparing " + taskSpec.name + " with");
-            dumpTask(task, 0, "");
-        }
-
+            new TaskTreeEncoder().encode(taskInstance, System.err);
+        }
+
+        ITask task = taskInstance.getTask();
+        
         if (("Event".equals(taskSpec.type) && (!(task instanceof IEventTask))) ||
             ("TextInputEvent".equals(taskSpec.type) &&
@@ -396 +292 @@
             if (doTrace) {
                 System.err.println("task types do not match: " + taskSpec.type + " != " +
-                    task.getClass().getSimpleName() + "\n");
+                                   task.getClass().getSimpleName() + "\n");
             }
             return false;
@@ -440 +336 @@
             }
         }
-
-        if (((taskSpec.children == null) && (task.getChildren().size() > 0)) ||
-            ((taskSpec.children != null) && (taskSpec.children.length != task.getChildren().size())))
+        
+        // check the task name against the map
+        if (tasks.containsKey(taskSpec.name)) {
+            if (!tasks.get(taskSpec.name).equals(task)) {
+                if (doTrace) {
+                    System.err.println("the task instance is not of the expected task: " +
+                                       taskSpec.name + " != " + task + "\n");
+                }
+                return false;
+            }
+        }
+        else if (tasks.containsValue(task)) {
+            if (doTrace) {
+                System.err.println("the task of the task instance " + taskSpec.name +
+                                   " should be different to another one but it isn't\n");
+            }
+            return false;
+        }
+        else {
+            tasks.put(taskSpec.name, task);
+        }
+
+        if (((taskSpec.children == null) && (taskInstance.getChildren().size() > 0)) ||
+            ((taskSpec.children != null) &&
+             (taskSpec.children.length != taskInstance.getChildren().size())))
         {
             if (doTrace) {
@@ -448 +366 @@
                     ("numbers of children do not match: " +
                      (taskSpec.children == null ? "0" : taskSpec.children.length) + " != " +
-                     (task.getChildren() == null ? "0" : task.getChildren().size()) + "\n");
+                     (taskInstance.getChildren() == null ? "0" :
+                          taskInstance.getChildren().size()) + "\n");
             }
             return false;
         }
 
-        Iterator<ITaskTreeNode> children = task.getChildren().iterator();
+        Iterator<ITaskInstance> children = taskInstance.getChildren().iterator();
         if (taskSpec.children != null) {
             for (TaskSpec child : taskSpec.children) {
-                if (!taskSpecEqualsTask(child, children.next())) {
+                if (!taskSpecEqualsTaskInstance(child, children.next(), tasks)) {
                     if (doTrace) {
                         System.err.println("one of the children does not match\n");
@@ -478 +397 @@
         }
     }
-
-    /**
-   *
-   */
-    private void dumpTaskMap(Map<ITaskTreeNode, Integer> taskMap) {
-        System.err.println();
-        for (Map.Entry<ITaskTreeNode, Integer> entry : taskMap.entrySet()) {
-            dumpTask(entry.getKey(), entry.getValue(), "");
-            System.err.println();
-        }
-    }
-
-    /**
-     *
-     */
-    private void dumpTask(ITaskTreeNode task, int count, String indent) {
-        System.err.print(indent);
-        System.err.print(task);
-        System.err.print(" ");
-        System.err.print(task.getDescription());
-        System.err.print(" ");
-
-        if (count > 0) {
-            System.err.print("(");
-            System.err.print(count);
-            System.err.print(" occurrences)");
-        }
-
-        System.err.println();
-
-        if ((task.getChildren() != null) && (task.getChildren().size() > 0)) {
-            for (ITaskTreeNode child : task.getChildren()) {
-                dumpTask(child, 0, indent + "  ");
-            }
-        }
-    }
     
     /**
-     * TODO comment
-     * 
-     * @version $Revision: $ $Date: $
-     * @author 2011, last modified by $Author: $
+     *
      */
     private class TaskSpec {

trunk/autoquest-test-utils/src/main/java/de/ugoe/cs/autoquest/tasktrees/TaskTreeDecoder.java

@@ -26 +26 @@
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ISelection;
 import de.ugoe.cs.autoquest.tasktrees.treeifc.ISequence;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTreeBuilder;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTreeNode;
-import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskTreeNodeFactory;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITask;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskBuilder;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskFactory;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstance;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.ITaskInstanceList;
+import de.ugoe.cs.autoquest.tasktrees.treeifc.IUserSession;
 import de.ugoe.cs.autoquest.test.DummyGUIElement;
 
@@ -37 +40 @@
  * @author 2012, last modified by $Author: patrick$
  */
-public class TaskTreeInstantiator {
-    
-    /** */
-    private static Pattern taskPattern = Pattern.compile("([^{}]+)\\{|\\}");
-    
-    /** */
-    private static Pattern taskDetailsPattern =
+public class TaskTreeDecoder {
+    
+    /** */
+    private static Pattern taskInstancePattern = Pattern.compile("([^{}]+)\\{|\\}");
+    
+    /** */
+    private static Pattern taskInstanceDetailsPattern =
         Pattern.compile("\\s*(\\w*)\\s*([\\w\\(\\)\"]*)\\s*((\\w*)|(\".*\"))?");
     
     /** */
-    private ITaskTreeNodeFactory taskTreeNodeFactory;
-    
-    /** */
-    private ITaskTreeBuilder taskTreeBuilder;
+    private ITaskFactory taskFactory;
+    
+    /** */
+    private ITaskBuilder taskBuilder;
     
     /** */
     Map<String, IEventTarget> targets = new HashMap<String, IEventTarget>();
     
+    /** */
+    Map<String, ITask> tasks = new HashMap<String, ITask>();
+    
     /**
      *
      */
-    public TaskTreeInstantiator(ITaskTreeNodeFactory taskTreeNodeFactory,
-                                ITaskTreeBuilder taskTreeBuilder)
-    {
+    public TaskTreeDecoder(ITaskFactory taskFactory, ITaskBuilder taskBuilder) {
         super();
-        this.taskTreeNodeFactory = taskTreeNodeFactory;
-        this.taskTreeBuilder = taskTreeBuilder;
+        this.taskFactory = taskFactory;
+        this.taskBuilder = taskBuilder;
     }
 
@@ -69 +73 @@
      *
      */
-    public ITaskTreeNode instantiateTaskTree(String taskTreeSpec) {
-        ITaskTreeNode task = null;
-
-        Matcher taskMatcher = taskPattern.matcher(taskTreeSpec);
+    public ITaskInstanceList decode(String taskTreeSpec) {
+        ITaskInstanceList taskInstanceList = null;
+
+        Matcher taskMatcher = taskInstancePattern.matcher(taskTreeSpec);
 
         if (taskMatcher.find()) {
-            task = parseTask(taskMatcher);
+            taskInstanceList = parseTaskInstanceList(taskMatcher);
         }
         
@@ -82 +86 @@
         }
         
-        return task;
+        return taskInstanceList;
     }
 
@@ -88 +92 @@
      * 
      */
-    private ITaskTreeNode parseTask(Matcher taskMatcher) {
+    private ITaskInstanceList parseTaskInstanceList(Matcher taskMatcher) {
         if ("}".equals(taskMatcher.group(1))) {
-            throw new IllegalArgumentException("invalid task specification");
+            throw new IllegalArgumentException("invalid task instance list specification");
         }
         
         String taskDetails = taskMatcher.group(1);
         
-        Matcher matcher = taskDetailsPattern.matcher(taskDetails);
+        Matcher matcher = taskInstanceDetailsPattern.matcher(taskDetails);
         
         if (!matcher.find()) {
@@ -101 +105 @@
         }
 
-        ITaskTreeNode task;
-        
         String type = matcher.group(1);
         
-        String targetId = matcher.group(2);
-        if ((matcher.group(4) != null) && (!"".equals(matcher.group(4).trim()))) {
-            targetId += matcher.group(4).trim();
-        }
-        
-        IEventTarget target = targets.get(targetId);
-        
-        if (target == null) {
-            target = new DummyGUIElement(targetId);
-            targets.put(targetId, target);
-        }
-        
-        if ("Sequence".equals(type)) {
-            task = taskTreeNodeFactory.createNewSequence();
-        }
-        else if ("Selection".equals(type)) {
-            task = taskTreeNodeFactory.createNewSelection();
-        }
-        else if ("Iteration".equals(type)) {
-            task = taskTreeNodeFactory.createNewIteration();
-        }
-        else if ("Optional".equals(type)) {
-            task = taskTreeNodeFactory.createNewOptional();
+        ITaskInstanceList list;
+        
+        if ("UserSession".equals(type)) {
+            list = taskFactory.createUserSession();
+        }
+        else if ("TaskInstances".equals(type)) {
+            list = taskFactory.createNewTaskInstance(taskFactory.createNewSequence());
         }
         else {
-            task = taskTreeNodeFactory.createNewEventTask(new StringEventType(type), target);
+            throw new IllegalArgumentException("unknown type of task instance list: " + type);
+        }
+        
+        while (taskMatcher.find() && !"}".equals(taskMatcher.group(0))) {
+            ITaskInstance childInstance = parseTaskInstance(taskMatcher);
+            
+            if (!(list instanceof IUserSession)) {
+                taskBuilder.addChild
+                    ((ISequence) ((ITaskInstance) list).getTask(), childInstance.getTask());
+            }
+
+            taskBuilder.addTaskInstance(list, childInstance);
+        }
+
+        return list;
+    }
+
+    /**
+     * 
+     */
+    private ITaskInstance parseTaskInstance(Matcher taskMatcher) {
+        if ("}".equals(taskMatcher.group(1))) {
+            throw new IllegalArgumentException("invalid task instance specification");
+        }
+        
+        String taskDetails = taskMatcher.group(1);
+        
+        Matcher matcher = taskInstanceDetailsPattern.matcher(taskDetails);
+        
+        if (!matcher.find()) {
+            throw new IllegalArgumentException("could not parse task details");
+        }
+
+        String type = matcher.group(1);
+        String id = matcher.group(2);
+        
+        ITask task = tasks.get(id);
+        
+        if (task == null) {
+            if ("Sequence".equals(type)) {
+                task = taskFactory.createNewSequence();
+            }
+            else if ("Selection".equals(type)) {
+                task = taskFactory.createNewSelection();
+            }
+            else if ("Iteration".equals(type)) {
+                task = taskFactory.createNewIteration();
+            }
+            else if ("Optional".equals(type)) {
+                task = taskFactory.createNewOptional();
+            }
+            else {
+                IEventTarget target = targets.get(id);
+            
+                if (target == null) {
+                    target = new DummyGUIElement(id);
+                    targets.put(id, target);
+                }
+            
+                task = taskFactory.createNewEventTask(new StringEventType(type), target);
+            }
+            
+            tasks.put(id, task);
         }
         
         if ((matcher.group(5) != null) && (!"".equals(matcher.group(5).trim()))) {
-            taskTreeBuilder.setDescription(task, matcher.group(5).trim());
-        }
-
+            taskBuilder.setDescription(task, matcher.group(5).trim());
+        }
+
+        ITaskInstance instance = taskFactory.createNewTaskInstance(task);
+        
         while (taskMatcher.find() && !"}".equals(taskMatcher.group(0))) {
+            ITaskInstance childInstance = parseTaskInstance(taskMatcher);
+            
             if (task instanceof ISequence) {
-                taskTreeBuilder.addChild((ISequence) task, parseTask(taskMatcher));
+                taskBuilder.addChild((ISequence) task, childInstance.getTask());
             }
             else if (task instanceof ISelection) {
-                taskTreeBuilder.addChild((ISelection) task, parseTask(taskMatcher));
+                taskBuilder.addChild((ISelection) task, childInstance.getTask());
             }
             else if (task instanceof IIteration) {
-                if ((task.getChildren() == null) || (task.getChildren().size() == 0)) {
-                    taskTreeBuilder.setChild((IIteration) task, parseTask(taskMatcher));
-                }
-                else {
+                if (((IIteration) task).getMarkedTask() == null) {
+                    taskBuilder.setMarkedTask((IIteration) task, childInstance.getTask());
+                }
+                else if (!((IIteration) task).getMarkedTask().equals(childInstance.getTask())) {
                     throw new IllegalArgumentException
                         ("can not add more than one child to an iteration");
@@ -154 +206 @@
             }
             else if (task instanceof IOptional) {
-                if ((task.getChildren() == null) || (task.getChildren().size() == 0)) {
-                    taskTreeBuilder.setChild((IOptional) task, parseTask(taskMatcher));
-                }
-                else {
+                if (((IOptional) task).getMarkedTask() == null) {
+                    taskBuilder.setMarkedTask((IOptional) task, childInstance.getTask());
+                }
+                else if (!((IOptional) task).getMarkedTask().equals(childInstance.getTask())) {
                     throw new IllegalArgumentException
                         ("can not add more than one child to an optional");
@@ -164 +216 @@
             else {
                 throw new IllegalArgumentException("can not add children to something that is no " +
-                                                   "sequence, selection, or iteration");
-            }
-        }
-
-        return task;
+                                                   "sequence, selection, iteration, or optional");
+            }
+            
+            taskBuilder.addChild(instance, childInstance);
+        }
+
+        return instance;
     }