在32位和64位环境中具有Windows身份验证的SQLServer连接

Question

I have a Java Application which is distributed to a few users. The application connets to a SQLServer Database using windows authentification. From several SO-Posts ( SO6938717 , SO17277001 ) I learned that it is common practice to set a path to the needed library in the VM arguments.

java -Djava.library.path=/path/to/my/dll -jar /my/classpath/goes/here MainClass

My Application runs on 32- and 64bit environments, but for every environment there is a specific library with the same name: sqljdbc_auth.dll.

I can set two paths as VM arguments: java -Djava.library.path=/auth/x86;/auth/x64 -jar /my/classpath/goes/here MainClass

But this doesn't work. How can I ensure, that windows authentification works in 32- and 64bit environments?

Answer 1

Have a look here:

possible-values-of-processor-architecture

With this in mind you can distribute your app this way:

/libs/yourjarfiles.jar
/AMD64/sqljdbc_auth.dll (the 64bit version)
/x86/sqljdbc_auth.dll (the 32 bit version)

And call it using

java -Djava.library.path=.\%PROCESSOR_ARCHITECTURE%\ -jar /my/classpath/goes/here MainClass

Absolute Path to your install might be a good idea in library-path setting.

EDIT: Addressing the mentioned concerns for 32bit Java on 64bit host

Helper-Class: Architecture.java

public class Architecture {    
    public static void main(String[] args) {
        System.out.print(System.getProperty("os.arch"));
    }   
}

CMD to start your program

@ECHO OFF
for /f %%i in ('java -classpath /my/classpath/goes/here/ Architecture') do set JAVA_ARCH=%%i
java -Djava.library.path=path/to/dlls/%JAVA_ARCH%/ -cp /my/classpath/goes/here MainClass

You'd have to name your directories like this to match possible os.arch values:

/x86  - 32 bit DLL goes here
/amd64  - 64 bit DLL goes here

I guess if you'd know the path for the libraries you could even append that path based on os.arch System property at runtime of MainClass .