CVS Comments added to Code

[Lisa Carter]

Hello Group,

I saw a neat trick that one of my co-workers did. He added some comments to the Java code. When the committed in cvs, the code is updated with the comments entered into CVS. My question is where can I learn more about this neat trick. I wanted to understand it better. He's been using it for awhile and didn't know where I could get more info. Any info you have that can point me in the right direction would be great. Thanks in advance.

[Ernest Friedman-Hill]

Do you just mean things like

$Id: JoglModel3D.java,v 1.39 2005/10/11 22:04:50 ejfried Exp $

To get a comment like that, which is always kept updated with the file version, committer, commit date and time, you just put "$Id$" into your source. It'll be expanded the next time you commit.

Here's some other keyword substitutions, from the CVS info page:

 
`$Author$'
     The login name of the user who checked in the revision.
 
`$Date$'
     The date and time (UTC) the revision was checked in.
 
`$Header$'
     A standard header containing the full pathname of the RCS file,
     the revision number, the date (UTC), the author, the state, and
     the locker (if locked).  Files will normally never be locked when
     you use CVS.
 
`$Id$'
     Same as `$Header$', except that the RCS filename is without a path.
 
`$Name$'
     Tag name used to check out this file.  The keyword is expanded
     only if one checks out with an explicit tag name.  For example,
     when running the command `cvs co -r first', the keyword expands to
     `Name: first'.
 
`$Locker$'
     The login name of the user who locked the revision (empty if not
     locked, which is the normal case unless `cvs admin -l' is in use).
 
`$Log$'
     The log message supplied during commit, preceded by a header
     containing the RCS filename, the revision number, the author, and
     the date (UTC).  Existing log messages are _not_ replaced.
     Instead, the new log message is inserted after `$Log:...$'.  Each
     new line is prefixed with the same string which precedes the
     `$Log' keyword.  For example, if the file contains:
 
            /* Here is what people have been up to:
             *
             * $Log: frob.c,v $
             * Revision 1.1  1997/01/03 14:23:51  joe
             * Add the superfrobnicate option
             *
             */
    then additional lines which are added when expanding the `$Log'
     keyword will be preceded by `   * '.  Unlike previous versions of
     CVS and RCS, the "comment leader" from the RCS file is not used.
     The `$Log' keyword is useful for accumulating a complete change
     log in a source file, but for several reasons it can be
     problematic.  *Note Log keyword::.
 
`$RCSfile$'
     The name of the RCS file without a path.
 
`$Revision$'
     The revision number assigned to the revision.
 
`$Source$'
     The full pathname of the RCS file.
 
`$State$'
     The state assigned to the revision.  States can be assigned with
     `cvs admin -s'--see *Note admin options::.
 

[Ilja Preuss]

I actually don't like this feature very much. Your IDE should provide this information to you in a much more comfortable way, anyway (like the "Resource History" view in Eclipse). If it does, it just adds clutter to the code, in my opinion.

I guess it can be valuable when you print your sources a lot, though, so your mileage might certainly vary...

[Mr. C Lamont Gilbert]

it works well for when you remove your code from the ide environment. such as printing as you said.

you can find information like this in the 'cederqvist' or whatever they are calling the help files of CVS

Google 4tw.

[Lisa Carter]

thanks for the info. I tried to look up the codes in eclipse but no luck. We have to list all of the changes in our source code and this would be the easiest way. It stops me from adding commentsin CVS and then in my code. Using these variables allows the comments to autmatically be added. Thanks again for your help.