aimmath-developers

Re: [Aimmath-developers] why do we need jdk

[Alex S. <aw...@yo...>]

Hi

For your information, the JRE makes its location available as follows:

Unix:
The JAVA_HOME variable is required for proper operation so should always be
set if it is installed.

Windows:
The install process writes the location in the registry. Look under
HKEY_LOCAL_MACHINE\Software\JavaSoft\Java Runtime Environment
There you will find keys for each version which has been installed. In each
such key there is a "Java Home" string value.

On windows your install process should always check for locations from the
registry since the names can be changed. For example it doesn't actually
have to be "C:\Windows"; you can call it what you like. Also I have "E:\" as
my program files directory, not "C:\Program Files" for example.
The windows directory is set in the environment (WINDIR) and also in the
registry. Others can be found only in the registry.
The following keys are good places to look for Windows paths:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Setup
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\explorer\Shell
Folders
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\explorer\User
Shell Folders
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell
Folders
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User
Shell Folders
Application paths can often be found by seaching in:
HKEY_LOCAL_MACHINE\Software
Also many executable file locations are stored under:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths

Paths stored in HKEY_LOCAL_MACHINE are of course system wide while those in
HKEY_CURRENT_USER are for the current user only.

I hope this information helps.

Alex

RE: [Aimmath-developers] why do we need jdk

[Neil S. <N.P...@sh...>]

> Unix:
> The JAVA_HOME variable is required for proper operation so should
> always be set if it is installed.

Agreed; the AIM installation script already looks for this.

> Windows:
> The install process writes the location in the registry. Look under
> HKEY_LOCAL_MACHINE\Software\JavaSoft\Java Runtime Environment
> There you will find keys for each version which has been
> installed. In each
> such key there is a "Java Home" string value.
>
> On windows your install process should always check for locations from the
> registry since the names can be changed. For example it doesn't actually
> have to be "C:\Windows"; you can call it what you like. Also I
> have "E:\" as
> my program files directory, not "C:\Program Files" for example.
> The windows directory is set in the environment (WINDIR) and also in the
> registry. Others can be found only in the registry.

Clearly Alex is right that we should get information from the registry, if
we can.  However, I do not know how to write a batch file or a Maple script
that consults the registry - does anyone else?

Ideally, we should work out how to do the usual Install Shield thing for
installation under Windows.  A while ago I installed Microsoft Visual
Studio,
which ought to let me do this, but there are many things I would need to
learn beforehand.

Neil