EJB Classloader issue (dmcl40 library.dll already loaded)

I have written a stateless session bean. The session bean calls a documentum connection pool. This connection pool are java classes that use a dll (dmcl40.dll).
The Project is wrapped into a DC (one for ejb, one for app libs)
The dll-directory is set in the PATH environmentvariable.
Also, I set the classpath to my jar files in application-j2ee-engine.xml (tab expert settings -> classpath).
My problem is the EJB classloading. Any time the createSession method in the EJB (documentum) tries to create a session pool, i get the dmcl40 library already loaded error.
1. Where do I have to set the path to the library in WebAS to fix this?
2. is there a setting in the VisualAdmin, where one can set the path. Where can i set the path for parent classloader?
I am greateful for any hints.
thanks markus

Hi Markus,
Can u please let me know how did u solve ur problem?..
I am facing same problem and not able to fix it. So ur answer may be greatful to fix my problem..
Thanks in Advance.
Waiting ur Reply.
Best Regards,
Sadik.

Similar Messages

Error: native library oljdbc40.dll already loaded in another classloader

Hi, we're using Oracle 8iLite in combination with Tomcat (on WinNT4.0) to run servlets accessing our OLite db. We use a deployed db (Deployment tool: PolUtil.exe) and pure JDBC connections.
When starting tomcat, the servlet is automatically initialized (exactly once!). It comes to the point, where a database connection is to be established. At this point, we get the following error message:
Native Library E:\MyServer\DB\BIN\oljdbc40.dll already loaded in another classloader
The strange thing is, that this error only occurs on some machines. There are no other java apps running.
Where does this error come from, and how can someone avoid this seemingly arbitrary error?
Thanks in advance for your time, Holger
null

You are having some problems with that Oracle Driver and Orion.
Do you have any JSP at your Installation that work with Oracle?
Orion needs to know where that Diver is located is that Driver in
some package that is in Orion's Class Path?

Native Library ocijdbc8.dll already loaded in another classloader

Hi,
help me please!
I have Platform: Win2000/Orion/JSP + Oracle 8.1.7
and while using this testdb.jsp file
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i get error:
java.lang.UnsatisfiedLinkError: Native Library C:\oracle\ora81\bin\ocijdbc8.dll already loaded in another classloader
testdb.jsp
<%@ page import="java.util.*" %>
<%@ page import="java.sql.*" %>
<%
String user = "sa";
String password = "dbo";
String jdbcClass = "oracle.jdbc.driver.OracleDriver";
String jdbcURL = "jdbc:oracle:oci8:@DB02";
Connection conn = null;
PreparedStatement pstmt = null;
Statement stmt = null;
ResultSet rs = null;
try
Properties props = new Properties();
props.put("user", user);
props.put("password", password);
Driver myDriver = (Driver) Class.forName(jdbcClass).newInstance();
conn = myDriver.connect(jdbcURL, props);
catch (Exception e)
e.printStackTrace(response.getWriter());
try
stmt = conn.createStatement();
rs = stmt.executeQuery("select * from fxqs_users");
while(rs.next())
out.print("User: " + rs.getString("LOGIN") + "<hr size=1>");
rs.close();
stmt.close();
catch(Exception e)
e.printStackTrace(response.getWriter());
%>
Error:
500 Internal Server Error
java.lang.UnsatisfiedLinkError: Native Library C:\oracle\ora81\bin\ocijdbc8.dll already loaded in another classloader
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1346)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1306)
at java.lang.Runtime.loadLibrary0(Runtime.java:749)
at java.lang.System.loadLibrary(System.java:820)
at oracle.jdbc.oci8.OCIDBAccess.logon(OCIDBAccess.java:228)
at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:249)
at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:365)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:260)
at /fxqs/admin/index.jsp._jspService(/fxqs/admin/index.jsp.java:222) (JSP page line 185)
at com.orionserver[Orion/1.5.2 (build 10460)].http.OrionHttpJspPage.service(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._ah._rad(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)].server.http.JSPServlet.service(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._cxb._abe(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._cxb._uec(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._io._twc(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._io._gc(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._if.run(Unknown Source)
have you any solutions?

You are having some problems with that Oracle Driver and Orion.
Do you have any JSP at your Installation that work with Oracle?
Orion needs to know where that Diver is located is that Driver in
some package that is in Orion's Class Path?

Library ocijdbc8.dll already loaded in another classloader

Hi,
help me please!
I have Platform: Win2000/Orion/JSP + Oracle 8.1.7
and while using this testdb.jsp file
(simple select from some table and print result)
i get error:
java.lang.UnsatisfiedLinkError: Native Library C:\oracle\ora81\bin\ocijdbc8.dll already loaded in another classloader
testdb.jsp
<%@ page import="java.util.*" %>
<%@ page import="java.sql.*" %>
<%
String user = "sa";
String password = "dbo";
String jdbcClass = "oracle.jdbc.driver.OracleDriver";
String jdbcURL = "jdbc:oracle:oci8:@DB02";
Connection conn = null;
PreparedStatement pstmt = null;
Statement stmt = null;
ResultSet rs = null;
try
Properties props = new Properties();
props.put("user", user);
props.put("password", password);
Driver myDriver = (Driver) Class.forName(jdbcClass).newInstance();
conn = myDriver.connect(jdbcURL, props);
catch (Exception e)
e.printStackTrace(response.getWriter());
try
stmt = conn.createStatement();
rs = stmt.executeQuery("select * from fxqs_users");
while(rs.next())
out.print("User: " + rs.getString("LOGIN") + "<hr size=1>");
rs.close();
stmt.close();
catch(Exception e)
e.printStackTrace(response.getWriter());
%>
Error:
500 Internal Server Error
java.lang.UnsatisfiedLinkError: Native Library C:\oracle\ora81\bin\ocijdbc8.dll already loaded in another classloader
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1346)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1306)
at java.lang.Runtime.loadLibrary0(Runtime.java:749)
at java.lang.System.loadLibrary(System.java:820)
at oracle.jdbc.oci8.OCIDBAccess.logon(OCIDBAccess.java:228)
at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:249)
at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:365)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:260)
at /fxqs/admin/index.jsp._jspService(/fxqs/admin/index.jsp.java:222) (JSP page line 185)
at com.orionserver[Orion/1.5.2 (build 10460)].http.OrionHttpJspPage.service(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._ah._rad(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)].server.http.JSPServlet.service(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._cxb._abe(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._cxb._uec(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._io._twc(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._io._gc(Unknown Source)
at com.evermind[Orion/1.5.2 (build 10460)]._if.run(Unknown Source)
have you any solutions?

Make sure that the Oracle JDBC driver is in the "common" library location, not in the per-webapp location. If this were tomcat, I'd say put it in tomcat's own common/lib, rather than the webappname/WEB-INF/lib.
Basically, you want to make sure that the classes12.zip is only loaded once by one classloader.

UnsatisfiedLinkError ... ntvinv.dll already loaded in another classloader

Hi,
I'm trying to run a program using JCOM from the command line. My program is a
test runner which spawns a number of users in separate threads and runs a sequence
of requests. For every new user, the constructor which initializes the jcom proxy
object (IWlsTrigWrapProxy below) is called. Running the test with one user works
fine. In a multiple user test, the first user is successful, but when subsequent
users try to initialize I get the following message:
-----------------------8<---------------------------
BEA WebLogic 6.1 license found...
java.lang.UnsatisfiedLinkError: Native Library C:\bea\wlserver6.1\jcom\bin\ntvinv.dll
already loaded in another classloader
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1346)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1306)
at java.lang.Runtime.loadLibrary0(Runtime.java:749)
at java.lang.System.loadLibrary(System.java:820)
at com.bea.jcom.NativeObjRef.r(NativeObjRef.java)
at com.bea.jcom.Dispatch.a(Dispatch.java)
at com.bea.jcom.Dispatch.isNativeMode(Dispatch.java)
at com.bea.jcom.Dispatch.createDispatch(Dispatch.java)
at com.bea.jcom.Dispatch.<init>(Dispatch.java)
at xx.xxx.IWlsTrigWrapProxy.<init>(IWlsTrigWrapProxy.java:49)
at .......................
[ stuff deleted ]
-----------------------8<---------------------------
Is there an obvious reason for this? What can be done about it?
Best regards,
Lars Cronsioe

Hi Cronsioe,
I encountered the same error as you mentioned here when trying to access the COM
object using jcom.
The message I am getting is
UnsatisfiiedLinkError:getNegociateMessage()
I have put the jcom\bin in the path variable and the jcom.jar in the system classpath.
I have even sepcified the path for jcom\bin\ntvauth.dll in path variable.
Did you get any solution to your problem. If so please let me know. I appreciate
your responses.
Quraishi
"Lars Cronsioe" <[email protected]> wrote:
>
Clarifying my question from yesterday, I would like to add the following:
From the JCom Reference Guide, chapter 8, first section "From Java to
COM", it
seems that "The WebLogic jCOM runtime DCOM engine will allow multiple
simultaneous
requests to the same COM object". However, since nothing is said about
the native
mode, I draw the conclusion that simultaneous requests to the same COM
object
are not supported. Is this correct? What can I do about it?
Regards
Lars Cronsioe again

Libdb_java46.dll already loaded in another classloader

I'm trying to use DB XML in a servlet with Tomcat 5.5. In the init() method, I open a container and in destroy(), I do the cleanup.
The problem is that if I recompile my code and let Tomcat reload the webapp, I get the following error:
"java.lang.UnsatisfiedLinkError: Native Library libdb_java46.dll already loaded in another classloader"
I'm using Java 1.5.
Is there a way to get around this error? it is very annoying in development mode to stop and restart Tomcat each time I make a modification.
Thanks.

hi
try with putting db.jar and dblxml.jar into
$CATALINA_HOME/common/lib
more to read about classloading at following url
http://tomcat.apache.org/tomcat-5.5-doc/class-loader-howto.html
yurss rober

Java Connector. "sapjcorfc.dll already loaded in another classloader"

Dear all:
I'm fighting against a Java Connector problem.
I'm using:
-JCO version 2.16
-Apache Tomcat 5.5.17
I have written the environment variables:
CLASSPATH pointing where I have sapjco.jar, sapjcorfc.dll
Path where i have sapjco.jar, sapjcorfc.dll.
I try to make a webservice which calls a RFC function in SAP.
Java program compiles and Deploy OK.
I load the web service in Tomcat.
When I call the java server page, I get this error message from Tomcat:
org.apache.jasper.JasperException: JCO.classInitialize(): Could not load middleware layer 'com.sap.mw.jco.rfc.MiddlewareRFC'
JCO.nativeInit(): Could not initialize dynamic link library sapjcorfc Native Library C:\Traspas\Projecte\lib\sapjcorfc.dll already loaded in another classloader. java.library.path C:\Tomcat5.5.17\bin;.;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Java\jdk1.5.0_07\bin;C:\Traspas\Projecte\lib
     org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:510)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
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Seems that is trying to load twice sapjcorfc.dll?
I would be grateful if someone can give me help.
Thanks in advance.
Jordi

I received a message asking for further clarification. I try to further explain.
Be sure sapjco.jar is not included in the application. Doing so will lead the system to load more than one time the SAP Java Connector. Sapjco.jar has to be loaded only once in the server.
To do so (in Windows & Tomcat environment):
1-Be sure sapjco.jar is not included in the WEB-INF folder.
2-Put sapjcorfc.dll and librfc32.dll in c:Windowssystem32
3-Put sapjco.jar in c:Tomcatcommonlib
4-Add a reference to sapjco.jar in the project (In Eclipse: Project/Properties/Java Build Path, Tab Libraries, Add External JARs.
5-Compile and deploy the application. Generate War file. If ant gives problems, add proper command to find sapjco.jar (section <path id=u201Dpath.baseu201D>, <include name=u201Dsapjco.jaru201D>)
6-Load the WAR file in Tomcat.
7-Stop and Start Tomcat.
8-Run the application.
A related thread: [SAP J2EE engine problem|SAP J2EE engine problem]
Hope this helps.

Library is already loaded in another ClassLoader

Hi,
We have deployed our java application in NetWeaver. To decrpyt the logon cookie we are using the library libsapssoext.o. When we are tying to load this library it fails with the following exception.
[ERROR] SSO2Ticket.<clinit>() - Error during initialization of SSO2TICKET:
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Kindly advise.

Hi
The reason of such behavior might be in the mapping between the library and the old version of your Java class. It seems that the library when it was loaded first time is still mapped to the previous Java class version. Try to undeploy your application from the server and deploy it again.
BR, Siarhei

About JNI.***.dll already loaded in another class loader.

About JNI.***.dll already loaded in another class loader.
When I run a WEB program that use's JNI and DLL.The following excetpion information is throwed:
.***.dll already loaded in another class loader.(string "***" represents a dll name).
Help! Who can provide a solution.
Thanks.

i got the same problem before. seems it happens when
you load the .dll not using static{ } block. And when
your web application got an error and you fix it to
restart your application without restarting your
server, you will get this error message. You can
either put load library stuff in the static{ } block
or restart your server.And again.......
If all you want is to have the dll loaded, and it is loaded (that is why the exception occurs) then it does not matter that the exception occurs. You can catch it and ignore it.

JCo: "sapjcorfc.dll already loaded in another classloader"

Hi,
using Eclipse 3.2 I created some Java classes, which are using com.sap.mw.jco.*.
Now I create two JSP projects, which using my Java classes.
The JSPs are hosted by a Tomcat 5.5.
The reason of the error above is written in SAP note 542175.
Can somebody explain me please, which settings inside Eclipse 3.2 I have to make, that I can use my JSP applications at the same time.
What's to do on the Tomcat server?
In thread 15622 was written: "Add the library reference to the J2EE module ...", but how to do that?
Any help would be appreciated!
Regards,
Peter

Inside Eclipse open project properties, go to "Java Build Path" and then I pressed "Add variable", there I picked the SAPJCo.jar.
On tomcat installation directory I added the SAPJCo.jar inside file directory
"C:\Program Files\Apache Software Foundation\Tomcat 5.5\shared\lib"
I also extended the environment PATH variable with SAP JCo installation directory "C:\Program Files\SAP\sapjco-ntintel-2.1.7"
Hope this helps!
Peter

Problem : Native Library already loaded in another classloader

I created a shared library HaspKeyAPI.dll by using JNI and add path to Java class library. I need to call native functions in my servletAction class to check some information in a key. Sometimes not always, I met �java.lang.UnsatisfiedLinkError: Native Library C:\eclipse\workspace\HaspKey\SharedLib\HaspKeyAPI.dll already loaded in another classloader� problem. I have to restart tomcat server then to restart my web app.
Does anyone know how to fix it?
Thank you in advance!
////////////////////////////////////my native function class, a singleton class////////////////////////////////
package haspkey.api;
import java.util.Collection;
import java.util.Vector;
import haspkey.HardwareSecurityKey;
Public class HaspKeyAPI {
Public static final int KEYEXIST = 1;
//A Singleton Class
private static HaspKeyAPI haspKeyAPI;
private HaspKeyAPI()
public static HaspKeyAPI getSingletonObject()
if ( haspKeyAPI== null)
haspKeyAPI = new HaspKeyAPI();
return haspKeyAPI;
public Object clone()
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throw new CloneNotSupportedException();
/**********use native functions to call hasp C API***********/
public native int keyPresent(int password1, int password2);
public native int getId(int password1, int password2);
public native void readBlock(int startMemoryLocation, int size,
byte[] block, int password1, int password2);
public native void writeBlock(int startMemoryLocation,int size, byte[] block, int password1,
int password2);
public native boolean decodeData(int size, byte[] block, int password1,
int password2);
public native boolean encodeData(int size, byte[] block, int password1,
int password2);
static {
System.loadLibrary("HaspKeyAPI");
private int getPrivMachineSpeed(boolean decrypt, int pass1, int pass2, String MLOCRTypeCode){
byte[] block = new byte[8];
int privMachineSpeed = 0;
boolean isNumeric = true;;
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if(block.length!=8){
return -1;
}else{
String s = new String(block);
for(int n=0; n<3; n++){
if(s.charAt(n)<48 || s.charAt(n)>57){
isNumeric = false;
if(isNumeric){
privMachineSpeed = Integer.parseInt(s.substring(0,3));
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HardwareSecurityKey key = new HardwareSecurityKey();
if(keyPresent(pass1,pass2)==KEYEXIST){
key.setPrivKeyID(getId(pass1, pass2));
key.setPrivMachineSpeed(getPrivMachineSpeed(true, pass1,pass2, MLOCRTypeCode));
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import com.bowebellhowell.haspkey.api.HaspKeyAPI;
import com.bowebellhowell.winsort.vo.haspkey.HardwareSecurityKey;
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public static final String MLOCRTypeCode ="mmmmmmmmmmmmmmm";
public static final String AuthorizationCodes = "bbbbbbbbbbbbbbbb";
public static final int p1 = 0;
public static final int p2 = 0;
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at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1551)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1511)
at java.lang.Runtime.loadLibrary0(Runtime.java:788)
at java.lang.System.loadLibrary(System.java:834)
at haspkey.api.HaspKeyAPI.<clinit>(HaspKeyAPI.java:76)
at util.HaspKey.isKeyPresent(HaspKey.java:35)
at LogonAction (LogonAction .java:65)

Hi EveryBody:
i working in 2 servlets, these servlets import a login.jar library and login.jar call to Login.dll (a native Library)
then. when i start second servlet i have this message
java.lang.UnsatisfiedLinkError: Native Library dllLogin.dll already loaded in another classloader
i read about class loader and i know about a only one load for native library but i don't know how resolve this exception because both servlets need dllLogin.dll to validate the user
please anybody knows how or have any idea?
Kind Regards
Edson
--sorry i know. my english is very bad

Library already loaded Oracle OCI8

Hello !
I work with Weblogic 701, oracle 9.2.0.1 database, oracle 9.2.0.2 client, and
oracle jdbc drivers classes12.zip
When I connect with the oci8 (not the thin) driver and try to execute the application,
I get this error :
java.lang.UnsatisfiedLinkError: Native Library D:\oracle\ora92\bin\orageneric9.dll
already loaded in another classloader
I have to shutdown weblogic and start it again. If I redeploy my application,
I get the same error and I have to shutdown again ...
and when I connect with the thin driver and try to execute the extract method
on a XMLType object, I always have a sqlException.
I see on the web that the extract method can only be applied with the oci8 driver.
How can I do ???
Thx

OCI drivers use native code, you can only load a JNI/native library once. It
seems that this library is being loaded within your application, either more
than once, or most probably within weblogic itself. So when your application
tries to initialise oci8 drivers, it fails because weblogic has already done
so before your application tries it.
Do you have a jdbc pool configured from within weblogic that is using oci8
drivers. If so you might want to disable that, alternately your application
might want to use that db pool.
Haider
"Partyboy" <[email protected]> wrote in message
news:328_3f0423c7$[email protected]..
>
Hello !
I work with Weblogic 701, oracle 9.2.0.1 database, oracle 9.2.0.2 client,and
oracle jdbc drivers classes12.zip
When I connect with the oci8 (not the thin) driver and try to execute theapplication,
I get this error :
java.lang.UnsatisfiedLinkError: Native LibraryD:\oracle\ora92\bin\orageneric9.dll
already loaded in another classloader
I have to shutdown weblogic and start it again. If I redeploy myapplication,
I get the same error and I have to shutdown again ...
and when I connect with the thin driver and try to execute the extractmethod
on a XMLType object, I always have a sqlException.
I see on the web that the extract method can only be applied with the oci8driver.
>
How can I do ???
Thx

[XMLType]Native Library already loaded

Hi !
I work with oracle DB 9.2.0.3 and J2ee server.
I connect to the db with JDBC driver (oci8 client)
When I use the method CreateXML method (XDB.jar package) I have this error :
java.lang.UnsatisfiedLinkError: Native Library D:\oracle\ora92\bin\orageneric9.dll already loaded in another classloader
I have to shutdown and reopen my J2ee server ...
Any Idea ?

If you use the session of the myserver1, then store some value in session to identify that the library is loaded.
As a first step in myserver2, Check in session whether the value is set.
If you cannot propagate session information across myserver1 and myserver2, then
myserver1:
static
loadLibrary("YourDLL")
"Include this here..........."
This code will be there in some class
"Include this here..........."
Just write in ser file that DLL is loaded.
myserver2:
static
checkWhetherAlreadyLoaded();
loadLibrary("YourDLL");
Or have the loading of library alone in a class in a static method.
public class LoadClass
public static loadLibrary()
System.loadLibrary("YourDLL");
In myserver1, just call this.
In myserver2, before calling this method,
just call any native method - a test method will do
public boolean checkLoadedStatus()
try
// Call the testing nativemethod.
catch(UnsatisfiedLinkerError e)
try
LoadClass.loadLibrary();
return true;
catch(Exception e)
return false;
}

Bonjour java already loaded in another classloader error

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?

marcosRoriz wrote:
But I can't use another instance of IXCRegistry?You understand that you have two class loaders right?
The shared library is loaded by the OS into the application. There can be only one.
The VM wants to associate that single shared library with the class loader that loaded it.
One solution is to have a class loader for just that class. Note that the OS, not the VM, will not let you have two instances of the shared library so it is generally pointless (in terms of class loaders) to have more than one.

Unable to deploy App more than once, ClassLoader Issues

Here is a way to solve your problem.
try to use
Runtime.getRuntime().load(absolute_library_path);
However, make a copy of the library you tried to load and name it uniquely such
as
append the current miliseconds.
After completed loading the library into the Runtime, new File(new_library_path).delete();
or you can try to use deleteOnExit() (createdTempFile instead).
"Bob H" <[email protected]> wrote:
>
I am working on a project that relies on the SAP Java Connector (JCO).
This "connector"
consists of a JAR containing some Java classes, and some native platform
libraries
(i.e. DLLs for Windows). The problem is I can only deploy the application
once
on a running WL Server 7.0 node. If after the first deployment I remove
the application
(via the WL server console) and try to redeploy, deployment works fine,
but the
JVM will not be able to load the SAP JCO stuff... if fails on calling
the native
library with an ExceptionInInitializerError:
java.lang.ExceptionInInitializerError: JCO.classInitialize(): Could not
load middleware
layer 'com.sap.mw.jco.rfc.MiddlewareRFC' Native Library C:\WINDOWS\system32\sapjcorfc.dll
already loaded in another class loader
Based on this error message it appears that the class loader created
for the previous
deployment still exists (even though the application is no longer deployed),
and
therefore still has a hold on the native library (which apparently can't
support
multiple processes).
What I have to do is stop the server, start back up and then redeploy.
This is
a very exhausing ordeal during development, and also leads to a not-very-flexible
situation for production.
Does anyone know if there a way to terminate this other classloader instance
while
the server is running?
Thanks,
Bob

EJB Classloader issue (dmcl40 library.dll already loaded)

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