tag:blogger.com,1999:blog-7100397.post5231423216209608967..comments2022-10-01T10:49:59.431-07:00Comments on Mark Watson's artificial intelligence and Lisp hacking blog: Space4J: similar to Prevayler but takes advantage of Java 1.6 concurrent data access APIsMark Watson, author and consultanthttp://www.blogger.com/profile/05514730816583918651noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-7100397.post-84712970590559306282009-05-14T17:45:00.000-07:002009-05-14T17:45:00.000-07:00All about query language:
Space4J comes with a co...All about query language:<br /><br />Space4J comes with a complete and powerful indexing framework. You can do any query you want using 4 different types of indexes. This was another problem of Prevayler. Object querying is not trivial and if it is left to the user to solve this issue, using another framework or not, he will get totally lost.Sergio Oliveira Jr.https://www.blogger.com/profile/15614515419794420385noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-18714844426279935132009-05-14T17:43:00.000-07:002009-05-14T17:43:00.000-07:00Dimitri: There is no need for an abstract clock. T...Dimitri: There is no need for an abstract clock. That was a flaw in Prevayler architecture in my opinion. Again THERE IS NO NEED FOR CLOCK. Check Space4J and you will understand that a clock is useless.Sergio Oliveira Jr.https://www.blogger.com/profile/15614515419794420385noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-12317161019377960282008-09-22T07:53:00.000-07:002008-09-22T07:53:00.000-07:00Marco: OK, that makes sense.Dimitris: for some pro...Marco: OK, that makes sense.<BR/><BR/>Dimitris: for some problems, the equivalent of a very large persistent hash table works fine - no need for a relational database, RDF store, etc. with a formal query language. In anycase, I have had good success using Prevaler.Mark Watson, author and consultanthttps://www.blogger.com/profile/05514730816583918651noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-20370987863698014772008-09-22T02:00:00.000-07:002008-09-22T02:00:00.000-07:00Explain to me. How a SW guy can recommend data acc...Explain to me. How a SW guy can recommend data access lacking the notion of a query language??<BR/><BR/>These are mere toys: anyone can write a logging framework based on serialization in a weekend. And as far I see, space4j doesn't even include an abstract clock (and can't reliable reapply time-based commands). Even the old prevayler had more sense to that.Anonymoushttps://www.blogger.com/profile/07286834543482860937noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-54705712793355322572008-09-22T01:51:00.000-07:002008-09-22T01:51:00.000-07:00Their main revenue comes from financial, telecommu...Their main revenue comes from financial, telecommunications, and government (defense) sectors where they have pretty 'big' (way beyond $5million/year revenue) customers; as big customers provide a solid revenue, the startup offer makes sense (as it comes at almost no cost, no commercial grade support being provided) in fostering adoption and enriching the ecosystem around gigaspaces.Marco Fabbrihttps://www.blogger.com/profile/05281624649308561752noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-31406216794198657372008-09-21T08:09:00.000-07:002008-09-21T08:09:00.000-07:00Hello Marco,I have never looked carefully at GigaS...Hello Marco,<BR/><BR/>I have never looked carefully at GigaSpaces, but I will put it on my list. I wonder how successful their business model is (free use for individuals and companies with less than $5million/year revenue).<BR/><BR/>Thanks,<BR/>MarkMark Watson, author and consultanthttps://www.blogger.com/profile/05514730816583918651noreply@blogger.comtag:blogger.com,1999:blog-7100397.post-67662630593848755942008-09-21T07:51:00.000-07:002008-09-21T07:51:00.000-07:00Talking about concurrency and persistence, Gigaspa...Talking about concurrency and persistence, Gigaspace's approach based on space based architecture ( http://en.wikipedia.org/wiki/Space-based_architecture ) and Persistence as a Service ( http://natishalom.typepad.com/nati_shaloms_blog/2007/09/paas-persistenc.html ) looks interesting and promising for ease of development (simplicity inherited from tuple spaces programming model), performance (in memory data grid) and integration with existing technologies (e.g, Spring/OpenSpaces http://www.openspaces.org ).Marco Fabbrihttps://www.blogger.com/profile/05281624649308561752noreply@blogger.com