updated section 3

docs/teaching/exercises/answers/Answer1d.java

@@ -1,23 +0,0 @@
-/* *******************************************************************
- * Copyright (c) 2002 Palo Alto Research Center, Incorporated (PARC).
- * All rights reserved.
- * This program and the accompanying materials are made available
- * under the terms of the Common Public License v1.0
- * which accompanies this distribution and is available at
- * http://www.eclipse.org/legal/cpl-v10.html
- *
- * Contributors:
- *     PARC     initial implementation
- * ******************************************************************/
-
-package answers;
-
-aspect Answer1c {
-    declare error
-        : set(private * *)
-          && !(withincode(* set*(..))
-               || withincode(new(..))
-               || withincode(void figures.Point.move(int, int)))
-          && within(figures.*)
-        : "bad field set";
-}

docs/teaching/exercises/answers/Answer3a.java

@@ -14,10 +14,8 @@ package answers;
 
 import support.Log;
 
-import figures.Point;
-
 aspect Answer3a {
-    before(): execution(void Point.move(int, int)) {
-        Log.log("moving");
+    before(): execution(public * *(..)) && within(figures.*) {
+        Log.log(thisJoinPoint.toString());
     }
 }

docs/teaching/exercises/answers/Answer3b.java

@@ -19,8 +19,11 @@ import figures.Group;
 import figures.FigureElement;
 
 aspect Answer3b {
-    before():
-        execution(void Group.add(FigureElement)) && args(Point) {
-        Log.log("adding Point");
+    before(Object o):
+            execution(public * *(..))
+            && within(figures.*) && target(o)
+            && !withincode(public String toString(..)) // don't overflow!
+    {
+        Log.log(thisJoinPoint.toString() + " at " + o);
     }
 }

docs/teaching/exercises/answers/Answer3c.java

@@ -14,21 +14,11 @@ package answers;
 
 import support.Log;
 
-import figures.Point;
-import figures.Group;
-import figures.FigureElement;
+import figures.*;
 
 aspect Answer3c {
-    private Group Point.enclosingGroup = null;
-
-    before(Point p, Group g):
-        execution(void add(FigureElement)) && args(p) && target(g) {
-        p.enclosingGroup = g;
-    }
-
-    before(Point p):
-        call(void move(int, int)) && target(p) {
-        Log.log("moving as a part of " + p.enclosingGroup);
+    before():
+	execution(void Group.add(FigureElement)) && args(Point) {
+        Log.log("adding Point");
     }
-
 }

docs/teaching/exercises/build.xml

@@ -106,5 +106,10 @@
     <delete dir="dist" />
   </target>
 
+  <target name="javaclean">
+    <delete dir="dist" />
+  </target>
+
+
 </project>
 

docs/teaching/exercises/index.html

@@ -265,29 +265,26 @@ aspect,
 </p>
 
 <blockquote><PRE>
-$ ajc -Xlint -argfile base.lst
-
 $ java tests.Test2a
-.F.F.F....
-Time: 0.099
-There were 3 failures:
+.F..F....
+Time: 0.04
+There were 2 failures:
 1) testTooSmall(tests.Test2a)junit.framework.AssertionFailedError: should have thrown IllegalArgumentException
-2) testTooBig(tests.Test2a)junit.framework.AssertionFailedError: should have thrown IllegalArgumentException
-3) testMove(tests.Test2a)junit.framework.AssertionFailedError: should have thrown IllegalArgumentException
+2) testMove(tests.Test2a)junit.framework.AssertionFailedError: should have thrown IllegalArgumentException
 
 FAILURES!!!
-Tests run: 7,  Failures: 3,  Errors: 0
+Tests run: 7,  Failures: 2,  Errors: 0
 </PRE></blockquote>
 
 <p> But after compiling in the aspect...
 </p>
 
 <blockquote><PRE>
-$ ajc -Xlint -argfile base.lst
+$ ajc -Xlint -argfile base.lst answers/Answer.java
 
 $ java tests.Test2a
 .......
-Time: 0.097
+Time: 0.04
 
 OK (7 tests)
 </PRE></blockquote>
@@ -430,6 +427,15 @@ and call <code>Log.log(String)</code></p>
 <p> <strong>Tools:</strong> <code>target</code>
 </p>
 
+<p> AspectJ can expose the target object at a join point for tracing.
+In this exercise, you will print not only the join point information,
+but also the target object, with the form
+</p>
+
+<blockquote><pre>
+<em>thisJoinPointInfo</em> at <em>targetObject</em>
+</pre></blockquote>
+
 
 <h3>c. More specialized logging</h3>