[jira] Commented: (DERBY-223) Change programs under demo directory use consistent package names so IDEs do not report errors

["John H. Embretsen (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/DERBY-223?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12534290 ] 

John H. Embretsen commented on DERBY-223:
-----------------------------------------

I think there is a tradeoff here between simplicity and IDE (Eclipse?) compatibility (and Java recommended practices). 

First of all, this change will make things a little bit more complicated for users who run the demo outside an IDE. For example, this currently works (as described in the instructions):

$ cd demo/programs/simple/
$ export CLASSPATH=.:$DERBY_INSTALL/lib/derby.jar
$ java SimpleApp

The proposed change requires the user to do something like this:

$ cd demo/programs/simple/
$ export CLASSPATH=..:$DERBY_INSTALL/lib/derby.jar
$ java simple.SimpleApp

or this:

$ cd demo/programs/
$ export CLASSPATH=.:$DERBY_INSTALL/lib/derby.jar
$ java simple.SimpleApp

(in the latter case the database will end up in a common directory for all the demo programs - potentially confusing)

I'm just thinking that we should try to keep "simple" demos as simple as possible...

On the other hand, Eclipse users might benefit from this change (not sure how other IDEs handle this). 
And, there are other benefits of not using the default (unnamed) package, such as the ability to import and reuse the code. 
Does anyone else have opinions on this?

(Speaking of package names, we might want to follow recommendations in the Java language specification (§6.8.1) and use org.apache.derby... package names for all the demos).

Anyway, the current proposed patch changes the code but does not include required updates to the documentation (readme/example HTML files in the demo subdirectories). For example, with the simple demo, the current patch will result in the following error if instructions in java/demo/simple/example.html for running in embedded mode are followed verbatim:

$ java SimpleApp
Exception in thread "main" java.lang.NoClassDefFoundError: SimpleApp (wrong name: simple/SimpleApp)


> Change programs under demo directory use consistent package names so IDEs do not report errors
> ----------------------------------------------------------------------------------------------
>
>                 Key: DERBY-223
>                 URL: https://issues.apache.org/jira/browse/DERBY-223
>             Project: Derby
>          Issue Type: Improvement
>          Components: Demos/Scripts, Newcomer
>            Reporter: John Sisson
>            Assignee: Thomas Nielsen
>            Priority: Trivial
>         Attachments: d223.diff, d223.stat
>
>
> Currently if you build the demos under eclipse, it gives the following errors:
> Severity	Description	Resource	In Folder	Location	Creation Time
> 2	The declared package does not match the expected package nserverdemo	SimpleNetworkClientSample.java	derby-trunk/java/demo/nserverdemo	line 1	April 14, 2005 9:32:35 AM
> 2	The declared package does not match the expected package nserverdemo	SimpleNetworkServerSample.java	derby-trunk/java/demo/nserverdemo	line 1	April 14, 2005 9:32:35 AM
> 2	The declared package does not match the expected package simple	SimpleApp.java	derby-trunk/java/demo/simple	line 1	April 14, 2005 9:32:35 AM
> The following demo src files (and their associated documentation for running them) should be changed so that they specify the package "nserverdemo" so they are consistent with the other java source files in the same directory:
> java/demo/nserverdemo/SimpleNetworkClientSample.java
> java/demo/nserverdemo/SimpleNetworkServerSample.java
> The following demo src files (and their associated documentation for running them) should be changed so that they specify the package "simple" so they are consistent with the other java source files in the nserverdemo directory:
> java/demo/simple/SimpleApp.java

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.