Unload a dll loaded by a classloader in Java11 - classloader

Question

I had a scenario where I need to perform database connectivity using Java11 twice using Windows Authentication on SQL server.
Initially, the sqljdbc_auth.dll is loaded for the first call and the connection was successful. But, in order to make the connection second time at a different place, it throws an SQLException saying 'sqljdbc_auth.dll already loaded by another classloader'.
So, I need to unload the dll in between the two calls.
There is an option to do the same till Java8 version by invoking the finalize() on the classloader using reflection mechanism but unable to find an alternative in Java11
Sample code:
Here, I placed the sqljdbc_auth.dll in the PATH and jar named sql_jdbc.jar in the urls list and these are compatible with Java11
private static void loadFile(){
ClassLoader currentClassLoader = Thread.currentThread().getContextClassLoader();;
ClassLoader loader = new URLClassLoader(urls, ClassLoader.getSystemClassLoader()); // here, urls is an array and contains only a single sql_jdbc.jar path in it
Thread.currentThread().setContextClassLoader(loader);
Driver driver = (Driver)loader.loadClass("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
Connection connection = driver.connect("jdbc:sqlserver://IP-addr:1433;DatabaseName=db_name;SelectMethod=cursor;integratedSecurity=true", props);
//perform db actions here
Thread.currentThread().setContextClassLoader(currentClassLoader);
unloadDLL("sqljdbc_auth.dll",loader);
}
private synchronized static void unloadDllFile(String dllName, ClassLoader classLoader) throws Throwable {
try {
Field field = ClassLoader.class.getDeclaredField("nativeLibraries");
field.setAccessible(true);
Map<Object, Object> lib = (ConcurrentHashMap<Object, Object>) field.get(classLoader);
Set<Object> keyset = lib.keySet();
for (Object dllpath : keyset) {
if (dllpath.toString().contains(dllName)) {
Object o = lib.get(dllpath);
classLoader = null;
field = null;
lib.remove(dllpath);
keyset.remove(dllpath);
o = null;
System.gc();
}
}
} catch (Exception e) {
System.out.println("Exception in dll is "+e.getMessage());
}
}
There is a similar code in the second component but it throws an exception there.
Exception stacktrace while loading in the second component is:
com.microsoft.sqlserver.jdbc.SQLServerException: This driver is not configured for integrated authentication. ClientConnectionId:d19de7a1-d099-477c-9c18-0c4cd5807f5e
at com.microsoft.sqlserver.jdbc.SQLServerConnection.terminate(SQLServerConnection.java:2892)
at com.microsoft.sqlserver.jdbc.AuthenticationJNI.<init>(AuthenticationJNI.java:72)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.logon(SQLServerConnection.java:3636)
at com.microsoft.sqlserver.jdbc.SQLServerConnection$LogonCommand.doExecute(SQLServerConnection.java:3627)
at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:7194)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:2935)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:2456)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:2103)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectInternal(SQLServerConnection.java:1950)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:1162)
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:735)
at sample.java_samples.Sample2.loadFile(Sample2.java:66)
at sample.java_samples.Sample2.main(Sample2.java:23)
Caused by: java.lang.UnsatisfiedLinkError: Native Library C:\Windows\System32\sqljdbc_auth.dll already loaded in another classloader
at java.base/java.lang.ClassLoader$NativeLibrary.loadLibrary(ClassLoader.java:2456)
at java.base/java.lang.ClassLoader.loadLibrary0(ClassLoader.java:2684)
at java.base/java.lang.ClassLoader.loadLibrary(ClassLoader.java:2649)
at java.base/java.lang.Runtime.loadLibrary0(Runtime.java:829)
at java.base/java.lang.System.loadLibrary(System.java:1867)
at com.microsoft.sqlserver.jdbc.AuthenticationJNI.<clinit>(AuthenticationJNI.java:52)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.logon(SQLServerConnection.java:3635)
... 10 more
Thanks