Paul, The issue we are having with DataStore is that precisely what you are referring to. Each layer is trying to do its own connection in a separate thread to the server and Oracle is running out of connections. Some kind of connection pooling would probably solve this problem, but we haven't been focused on it for a while. It would probably require some changes to the DataStore class and I wasn't sure Vivid Solutions was finished with it yet.
The connection information is persisted in workbench-state.xml through the standard workbench blackboard method. Regarding the metadata list of layers concept, I basically felt that that was a .jmp file and didn't see a need to reinvent it. Merge Task/Archive just allows you to open multiple task files in the same project. regards, Larry On 5/29/07, Paul Austin <[EMAIL PROTECTED]> wrote: > > Hi Larry, > > I've just downloaded SkyJump and seen how the DataStores work and it looks > as if it is roughly what I'm looking for. > > I notice that when you save the Project to a .jmp file that the connection > information is duplicated for each layer. Does this mean that each layer > will connect directly to the database or do all the layers share a > connection from the connection manager. What would be nice is if this > information could be stored only once and referenced from the other layers. > > I see that the connection manager is preserved in the SkyJUMP installation, > where is this information stored in a windows install. > > Any idea when these plug-ins will be rolled into the OpenJUMP release I see > there is a difference in the version they have. > > For the file based concepts I was talking about, the list of layers is > defined in the metadata file so what I'd want to do is point it at the > directory then my plugin would generate the list of layers from the metadata > instead of the files. So this is slightly different from the usual just > selecting a bunch of files from a directory. > > I'm going to for now do an import of the "zip" based file type I have using > your MergeProjectPlugin as an example, ultimately I'd like to be able to > have it read directly from the file, but I think that may require some extra > resource management. > > Cheers, > Paul > > > > Larry Becker wrote: > Hi Paul, > > As usual, you are interested in many of the same things that I am. > The single DataSource multiple layer concept is currently only > implemented in WMS and MrSID (which is based on WMSLayer) and you > actually end up with only a single layer in JUMP, but you can manage > it as multiples. > > SkyJUMP has implemented the zip file with multiple layers as Merge > Task/Archive. It works much as you propose and even supports writing > back to the zip file with Save Selected Datasets. Loading multiple > files at one time is already supported in JUMP unless I don't > understand your concept. > > For databases we also have ArcSDE support which allows browsing and > loading multiple layers at once. > > We also support the DataStore concept in JUMP, but have had > concurrency issues with it. > > regards, > Larry > > On 5/29/07, Paul Austin <[EMAIL PROTECTED]> wrote: > > > All, > > I've been looking at the existing database and file plugins and the > com.vividsolutions.jump.io.datasource.DataSource class and > from what I > can tell there is a one to one relationship between a layer and a data > source. > > What I would like to do for some of the file and database based data > sources is to have the concept of a DataSource that can contain many > different layers. Within a project you would be able to select which > layers you wanted to view from that data source. > > In the database world this concept would relate to having a connection > to the data base using a java.sql.Connection. When adding the database > connection to a project there would be a UI that would list the > available layers (database tables) and the user could select which > layers they wish to view. This compares to the current PostGIS plug-in > where you have to manually enter the connection and table details for > each layer. > > When the project is closed then the "connection" must also be closed. > > In the Jump project file the "connection" parameters would be stored > once, then the data sources used for each layer would reference the > "connection" and have a different query for each table. > > Now if we look at a file based example, I have a file format which is > basically a zip file that contains one file for each layer along with > some metadata files. I would like to be able to open the zip file and > create a layer for each of the layers in the zip file. To do this I > would extract the file to the temp directory and as required load the > data from the individual files in the temp directory. Then when you > close the project the "connection" is closed by deleting the temporary > files. > > Another file based example would be to open a directory of files, > loading each layer file in that directory, this is basically the same as > the zip file idea but without the temporary files. > > In both the file cases once the file is loaded the first time the user > can select which of the layers to view. > > So the question is, does any of the existing functionality in JUMP allow > for multi-layer data sources? If not I'm going to do some prototyping > for the file format I have and then share this with the group for > comment to see if it would be useful elsewhere. > > After that I have an interest in Oracle connections so would need to do > the same kind of thing there. > > One other question, where would I find the code for writing out the > project .jmp XML files as I'd need to add the "connection" definitions > to this. > > Cheers, > Paul > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > > > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > -- http://amusingprogrammer.blogspot.com/ ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. 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