AppletTalk.com Java discussions newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  loading drivers          AppletTalk.com Forum Index -> Java and Databases View previous topic :: View next topic   Author Message Murat Tasan Guest Posted: Mon Jul 14, 2003 2:56 pm    Post subject: loading drivers I'm having a very confusing problem with my application... The problem is when I try to load JDBC drivers when my app is in a jar file. Here is a test case: public class Test { public static void main(String[] args) throws Exception { Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); System.out.println("sweet!"); } } Now, my $CLASSPATH is set fine, verified by running the above and getting: Quote: java Test sweet! Okay, so now I'll jar this file up and add a manifest addition... (for the main class)... Quote: jar -cmf MANIFEST.MF test.jar Test.class now I try to run it: Quote: java -jar test.jar and it starts to run (so manifest is fine), but gives me this: Exception in thread "main" java.lang.ClassNotFoundException: com.microsoft.jdbc.sqlserver.SQLServerDriver at java.net.URLClassLoader$1.run(URLClassLoader.java:198) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:186) at java.lang.ClassLoader.loadClass(ClassLoader.java:299) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:265) at java.lang.ClassLoader.loadClass(ClassLoader.java:255) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:315) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:140) at Test.main(Test.java:5) Quote: And the $CLASSPATH has NOT changed at all while doing this. So it worked when running from the .Class file, but not when running from the .jar file Any ideas? Am I just missing something here about .jar files? Thanks much, murat -- Murat Tasan [email]mxt6 (AT) po (DOT) cwru.edu[/email] [email]tasan (AT) eecs (DOT) cwru.edu[/email] [email]murat.tasan (AT) cwru (DOT) edu[/email] http://genomics.cwru.edu Back to top Jon Skeet Guest Posted: Mon Jul 14, 2003 4:13 pm    Post subject: Re: loading drivers Murat Tasan <tasan (AT) eecs (DOT) cwru.edu> wrote: Quote: And the $CLASSPATH has NOT changed at all while doing this. So it worked when running from the .Class file, but not when running from the .jar file The classpath environment variable (and command line option) isn't used when the -jar option is specified. -- Jon Skeet - <skeet (AT) pobox (DOT) com> http://www.pobox.com/~skeet/ If replying to the group, please do not mail me too Back to top Murat Tasan Guest Posted: Mon Jul 14, 2003 5:08 pm    Post subject: Re: loading drivers okay, well then, that sucks. does anyone know then how to specify additional classpaths when using the -jar option? i assume the java sdk classes are automatically included (they have to), and all of the classes in the executing jar file... but how do i then load classes not in either of those two locations? thanks for all the help! murat On Mon, 14 Jul 2003, Jon Skeet wrote: Quote: Murat Tasan <tasan (AT) eecs (DOT) cwru.edu> wrote: And the $CLASSPATH has NOT changed at all while doing this. So it worked when running from the .Class file, but not when running from the .jar file The classpath environment variable (and command line option) isn't used when the -jar option is specified. -- Murat Tasan [email]mxt6 (AT) po (DOT) cwru.edu[/email] [email]tasan (AT) eecs (DOT) cwru.edu[/email] [email]murat.tasan (AT) cwru (DOT) edu[/email] http://genomics.cwru.edu Back to top Jon Skeet Guest Posted: Tue Jul 15, 2003 7:26 am    Post subject: Re: loading drivers Murat Tasan <tasan (AT) eecs (DOT) cwru.edu> wrote: Quote: okay, well then, that sucks. No, it doesn't. It means that people can distribute jar files without worrying about whether someone will have some other version of a library they need on their classpath. Quote: does anyone know then how to specify additional classpaths when using the -jar option? Either use the extensions mechanism, or specify the classpath in the manifest. Quote: i assume the java sdk classes are automatically included (they have to), and all of the classes in the executing jar file... but how do i then load classes not in either of those two locations? See above - or create a ClassLoader instance explicitly which knows how to load the classes. In the case of a database, however, I believe it's problematic if you end up with drivers being loaded by child classloaders - hopefully someone here will have a solution for that if it's an issue for you though. -- Jon Skeet - <skeet (AT) pobox (DOT) com> http://www.pobox.com/~skeet/ If replying to the group, please do not mail me too Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         AppletTalk.com Forum Index -> Java and Databases All times are GMT Page 1 of 1   Jump to: Select a forum Java Newsgroups----------------Java DiscussionsWeb-based java games comp.lang.java 3D Graphics API's for Java Java: Support and criticism Java System Announcements comp.lang.java.api JavaBeans Java and CORBA Java and Databases comp.lang.java.developer Java GUI Toolkits Java Help comp.lang.java.javascript JVM, native methods and hardware comp.lang.java.misc Java Language Programming Security and Java comp.lang.java.setup Java Software Tools comp.lang.java.tech ibm.software.java.linux  Non-English Java Newsgroups----------------Java Language (German)Language Java (Français)Java (Italian)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.