Environment Variables in Spring?

[dleal]

I would like to know how to access to an environment variable in Spring. For example I would like to use some environment variable in order to set the url property:

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> 
      <property name="driverClassName"><value>org.hsqldb.jdbcDriver</value></property> 
      <property name="url"> 
        <value>jdbc&#58;hsqldb&#58;P&#58;/springapp/v6/springapp/db/test</value> 
      </property> 
    </bean>

but I don't know which environment variables are accepted by Spring configuration files and how to use them (syntax), for example: ${user.home}, $HOME, etc. Any way are there any Spring Environment variables, could be used on the Spring configuration files.

Thanks in advance,

David Leal

[Alarmnummer]

Take a look at the:
http://www.springframework.org/docs/...onfigurer.html

and
http://www.springframework.org/docs/...postprocessors


Btw:
it would be nice if I could evaluate some expressions in Spring (maybe by using something like ognl), so I can say:

<property name="timeout" value="ognl:60*60*24"/>

and even something like:

<property name="timeout" value="ognl:60*60*${hours}*fooBean.days"/>

[dleal]

Thanks Alarmnummer,

I am going to take a detailed look to this information, but I am afraid that
I am asking about somethink different.

What I like is to have access to some System Environment Variables. For example to refer one of the following system variables that shows the set dos command:

c:\> set

ALLUSERSPROFILE=C:\Documents and Settings\All Users
ANT_HOME=c:\archiv~1\Java\Apache\Ant\ant
APPDATA=C:\Documents and Settings\david\Datos de programa
APR_ICONV_PATH=C:\Archivos de programa\Subversion\iconv
CLASSPATH=.;S:\java\class;S:\java\lib;S:\java\resources
CommonProgramFiles=C:\Archivos de programa\Archivos comunes
COMPUTERNAME=BOSTON4BDRCHA
ComSpec=C:\WINDOWS\system32\cmd.exe
FP_NO_HOST_CHECK=NO
HOMEDRIVE=C:
HOMEPATH=\Documents and Settings\david
JAVA_HOME=C:\Java\j2sdk\j2sdk1.4.2_08
LOGONSERVER=\\BOSTON4BDRCHA
MuPAD_SWP_200=C:\Archivos de programa\swp40\MuPAD
MY_CLASSPATH=S:\java\class;S:\java\lib;S:\java\resources
MY_PATH=c:\archiv~1\Java\Apache\Ant\ant\bin;c:\archiv~1\cvs;C:\Java\j2sdk\bin
NUMBER_OF_PROCESSORS=1
OS=Windows_NT
Path=c:\archiv~1\MiKTeX\Main\miktex\bin;c:\archiv~1\Java\Apache\Ant\ant\bin;c:\archiv~1\cvs;C:\Java\j2sdk\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\ARCHIV~1\ULTRAE~1;c:\archiv~1\matlab6p5\bin\win32;c:\archiv~1\Subversion\bin
PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
PROCESSOR_ARCHITECTURE=x86
PROCESSOR_IDENTIFIER=x86 Family 6 Model 9 Stepping 5, GenuineIntel
PROCESSOR_LEVEL=6
PROCESSOR_REVISION=0905
ProgramFiles=C:\Archivos de programa
PROMPT=$P$G
SESSIONNAME=Console
SystemDrive=C:
SystemRoot=C:\WINDOWS
TEMP=C:\DOCUME~1\david\CONFIG~1\Temp
TMP=C:\DOCUME~1\david\CONFIG~1\Temp
USERDOMAIN=BOSTON4BDRCHA
USERNAME=david
USERPROFILE=C:\Documents and Settings\david
windir=C:\WINDOWS

What about if I want to use the system environment variable HOMEPATH on the myapp-servlet.xml. Is there any way to get a reference to this variable?

Thanks in adavance,

David

[Alarmnummer]

Thanks Alarmnummer,

I am going to take a detailed look to this information, but I am afraid that
I am asking about somethink different.

What I like is to have access to some System Environment Variables.

I think that is going to be complicated, see topics at:
http://www.google.nl/search?hl=nl&q=...e+zoeken&meta=

It seems there is no good way in Java to access them.

Btw:
you can access the system.properties with the links I have given you.

[jbetancourt]

I believe PropertyPlaceHo.... accesses the environment system properties too.

"....A configurer will also check against system properties (e.g. "user.dir") if it cannot resolve a placeholder with any of the specified properties. This can be customized via "systemPropertiesMode". "

[Alarmnummer]

I believe PropertyPlaceHo.... accesses the environment system properties too.

"....A configurer will also check against system properties (e.g. "user.dir") if it cannot resolve a placeholder with any of the specified properties. This can be customized via "systemPropertiesMode". "

Yes.. but the question is if you can access the environmental variables. And I don`t think this is going to be easy: check the google link.

[jbetancourt]

The google links are addressing getEnv(), which is deprecated. However, the javadoc for System.getProperty(String key), seems to still be recommended.

And, Spring uses that: propVal = System.getProperty(placeholder);

Of course, there are many issues with Java accessing system level stuff, but that is is where other languages really shine like Perl, Python, etc.

[Alarmnummer]

The google links are addressing getEnv(), which is deprecated. However, the javadoc for System.getProperty(String key), seems to still be recommended.

Yes.. but the question is: can you find the environmental variables in the System.properties.

[Colin Yates]

No, System.getProperty will not return environment variables. System.getEnv will (which isn't deprecated in 1.5).

[jbetancourt]

I just looked at both 1.4 and 1.5 api docs. System does have many differences, one of these is that getenv is not deprecated in 1.5. Fun.