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Because ActiveSpaces just like JavaSpace implements the basic concepts of a tuplespace that originated in Linda systems, you will find direct equivalents to the JavaSpace interface methods in the ActiveSpaces API. But the ActiveSpaces API is not directly compatible with the JavaSpace interface: this is because (beyond the fact that it is offering many other features that you will not find in the JavaSpace interface) ActiveSpaces is platform independent and stores tuples while JavaSpace is as the name indicates completely Java-centric and stores Java objects.
Thanks for the clarification. If I understand correctly, you can store C++, .Net as well as Java objects in ActiveSpace, in one space, as far as your objects could be serialized/deserialized(?)
You store Tuples in Spaces. Tuples (like Messages in a messaging system for example) are a platform independent map of fields. So you can have a Java application create a tuple from the values contained in a POJO, then put that tuple in a Space and then have a C application retrieve the tuple from the Space and put the field values of that tuple into it's own variables or structures.
Of course, we also support a field type of 'Blob' which you can use to store a serialized object in a Tuple but then you are limiting yourself to a single platform for that particular Space...
This gets more interesting. One of the important operations is read/take object(s) stored in the space using what is called Template match. So ActiveSpace uses ASCII text based comparison of object fields to find a match or matches. Am I right?
In ActiveSpaces, rather than simple template matching, you can use what we call filters on SpaceBrowers and Listeners. A filter is pretty much the part right of the WHERE clause in an SQL statement such as "Select * from Space where ..." (i.e. what you would put in the '...' part of this example). A filter is a String whose syntax is based on a subset of the SQL92 conditional expression syntax (very much like an JSM selector for example, except there's no concept of header and body fields and all of the tuple fields are available to filter on).
It is already GA and the 1.0 is available to selected customers
This is very interesting. FSI clients have been asking for a solution of this kind for a long. I am curious what open standard(s) do we follow, JavaSpace ...?