I'm using the java bonjour library (dns_sd.jar) in a web application running in Jboss web server.
When I start the server a Servlet finds every resource on the network with bonjour and returns to the user. The first time everything runs great but when I redeploy the web app I get:
java.lang.UnsatisfiedLinkError: Native Library C:\Windows\System32\jdns_sd.dll already loaded in another classloader
I already tried deletting the .dll and the samething happens.
Why does it even refer the .dll if I have the .jar lib in my web app?
Does anyone have any idea on how to fix this?
you do undeploy before you redeploy it. you no need to delete the dll file,it is not at all related to your error.it is an error of java and jboss.the problem is when you are redeploying it,it is unable to unload the libraries which you have loaded at the time of initial deployment.so better you check whether the library is loaded or not before you load the library next time,if it is already loaded do not load the library.
If you're using JBoss 7, try moving the jar file that uses the dll into a JBoss module. Restart JBoss so that it picks up the module. Modify your MANIFEST.MF file so that it contains "Dependencies: theNameYouGaveIt".
Where "theNameYouGaveIt" is the name you chose in your module's "yourModule/main/module.xml" file.
That way, JBoss doesn't reload the library over and over again. Then undeploy/redeploy your .ear or .war over and over again.
来源：https://stackoverflow.com/questions/9496617/java-error-native-library-already-loaded-in-another-classloader