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jkuritzky · Aug 1, 2001, 09:07 AM

I'd like to write a front-end for a PostgreSQL database. I've been toying with different languages/environments (Pure Java, Cocoa-Java, Realbasic, etc.) but I'd like to do it in Objective-C. Which leads to question 1:

Is there any way to access the database with the Objective-C libraries?

Because I couldn't find a way, I've been experimenting with JDBC. I've been able to get a Cocoa-Java app to work (at this point just testing that I can connect to the db and display a response), but I've had a lot of difficulty doing it in Objective-C with the java bridge. Here's what I've done:

I've written a java class that acts as an intermediary between the Objective-C code and the database (via JDBC). My problem now is getting this class across the bridge. I've tried using NSClassFromString, but I keep getting an error saying that my class is undeclared. So: How do I get my own classes across the bridge---where do I put them, how do I include them, etc.? Are there any tutorials around?

Another tutorial question: Are there any tutorials around for manipulating data sources and TableViews?

Thanks,

-Joshua

jkuritzky · Aug 1, 2001, 01:33 PM

I was able to get this working. After a lot of fooling around and a lot of internet searching, here's what I've discovered:

Apple's documentation on invoking Java from within Objective-C is missing some vital information. Here's what they have:

<BLOCKQUOTE>code:<HR><pre>
MyJavaClass = NSClassFromString(@"java.util.AJavaClass");MyJavaObj = [[MyJavaClass alloc] init];
[/code]

What they've neglected to include is that prior to this you must declare:
<BLOCKQUOTE>code:<HR><pre>
Class MyJavaClass;
id MyJavaObj;
[/code]

This is obvious when you think about it, but it took me an embarrassingly long time to figure it out. (I hope this helpful for future searchers.)

I'd still like recommendations on any NSDataSource -> NSTableView tutorials, especially involving the use of Java's ResultSet.

-Joshua