Differences

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--- contextawaretuples [2010/10/20 17:04] – cfscholl
+++ contextawaretuples [2010/10/20 17:48] (current) – cfscholl
@@ Line 40: / Line 40: @@
 ==== Context Provider ====
-The context provider in the context-aware tuple model is this devices which will inject tuples into the ambient such that collocated devices can read them. The code below shows the code in order to set up the context-aware tuple system and inject a tuple.
+The context provider in the context-aware tuple model is this device which injects tuples into the ambient. These tuples can potentially be read by collocated devices (if the context rule is satisfied). The code below shows the code in order to set up the context-aware tuple system and inject a tuple.
-This tuple of type inRoom with one field "MeetingRoom" will indicate the readers of this tuple that they are currently located in the meeting room. The injected tuple has a context rule attached which dictates that the receivers of this tuple have to have a tuple in their tuple space of type location and that the location field ?loc has to be within the boundaries of the roomArea. It is only when these conditions are satisfied that a context consumer will be able to read the tuple.
+In this case the tuple has type inRoom and one field "MeetingRoom". Being able to read this tuple will indicate that the reader is currently located in the meeting room.
+In order to make sure that only those devices which are located in the meeting room can read this tuple the injected tuple has a context rule attached. This rule indicates that the reader of the tuple has to have a tuple in his local tuple space of type location and the field ?loc has to be within the boundaries of the roomArea. It is only when these conditions are satisfied that a context consumer will be able to read the tuple.
 <code>
@@ Line 48: / Line 50: @@
 [Tuple(location , ?loc), WithinBoundary(roomArea , ?loc)];
 </code>
 ==== Context Consumer ====
+Because the context provider specifies the rules in order to read its tuples the code for the context consumer is very easy.
+The context consumer only has to read a tuple of type inRoom and register a listener for when such a tuple is read. In this case the listener will simply print that the user is currently in a particular room. The programmer can also react on the disappearance of a tuple by registering an outOfContext listener. In this case the listener will simply print that the user has move out of the room.
 <code>
 def cat := makeCatSystem();
-cat.whenever:	tuple(inRoom , ?name) read:	{
+cat.whenever:	Tuple(inRoom , ?name) read:	{
      display("You are in room " + name);
 } outOfContext: {
@@ Line 65: / Line 67: @@
 **Context-Aware Tuples for the Ambient**, C. Scholliers, E. Gonzalez Boix, W. De Meuter, T. D'Hondt. In Proceeding of
-the 12th International Symposium on Distributed Objects, Middleware, and Applications (DOA'10), LNCS. Srpinger Verlang, October 2010. ([[ http://prog.vub.ac.be/Publications/2010/vub-tr-soft-10-19.pdf | pdf]])
+the 12th International Symposium on Distributed Objects, Middleware, and Applications (DOA'10), LNCS. Springer Verlang, October 2010. ([[ http://prog.vub.ac.be/Publications/2010/vub-tr-soft-10-19.pdf | pdf]])