On 1/11/2011 8:45 AM, Ivan wrote:
That makes sense, also it is better to remove the codes
ProviderLocator.loadClass from the UtilLoader.loadClass method, or
that makes the function of loadClass method ambigurous.
For other reasons, I believe it is still necessary to have
ProviderLocator.loadClass() part of the loadClass() searches. This is a
different, internal situation where we're looking for a specific
provider for an interface.
Rick
2011/1/11 Rick McGuire <rick...@gmail.com <mailto:rick...@gmail.com>>
On 1/11/2011 7:35 AM, Ivan wrote:
I agree with Forrest that those code logic might need to be
updated. From the codes fragment below of UtilLoader
In the loadClass method, it will first try the
ProviderLocator.loadClass, but what ProviderLocation.loadClass
expect is an interface class name, like javax.rmi.CORBA.Util.
So those codes in the static block of Util, it should first try
to load it from ProviderLocator with service provider interface.
Comments ?
I think the static code in the Util class should be something like:
// Initialize delegate StringdelegateName=
(String)AccessController.doPrivileged(newGetSystemPropertyAction("javax.rmi.CORBA.UtilClass",
defaultDelegate)); try{ // this is a little bit recursive, but
this will use the full default search order for locating // this.
delegate =
(UtilDelegate)UtilLoader.loadServiceClass(delegateName,
Delegate.class).newInstance();
} catch(Throwablee) { org.omg.CORBA.INITIALIZEex=
neworg.omg.CORBA.INITIALIZE("Can not create Util delegate:
"+delegateName); ex.initCause(e); throwex; }
Where UtilLoader.loadServiceClass() is a method that functions
like UtilLoader.loadClass(), but takes both an interface class
name that is used to qualify the lookup.
Rick
-->
static public Class loadClass(String name, String codebase,
ClassLoader loader)
throws ClassNotFoundException {
Class result = null;
try {
return ProviderLocator.loadClass(name, null, loader);
} catch (ClassNotFoundException e) {
//skip
}
ClassLoader stackLoader = null;
ClassLoader thisLoader = UtilLoader.class.getClassLoader();
Class[] stack = _secman.getClassContext();
for (int i = 1; i < stack.length; i++) {
ClassLoader testLoader = stack[i].getClassLoader();
if (testLoader != null && testLoader != thisLoader)
{
stackLoader = thisLoader;
break;
}
}
......
<---
2011/1/11 Rick McGuire <rick...@gmail.com <mailto:rick...@gmail.com>>
On 1/11/2011 4:46 AM, Forrest Xia wrote:
Hi,
When I debug a corba related application, I managed to
trace into a piece of yoko code like this:
public class Util {
private static UtilDelegate delegate = null;
private static final String defaultDelegate =
"org.apache.yoko.rmi.impl.UtilImpl";
// To hide the default constructor we should implement
empty private constructor
private Util() {}
static {
// Initialize delegate
String delegateName =
(String)AccessController.doPrivileged(new
GetSystemPropertyAction("javax.rmi.CORBA.UtilClass",
defaultDelegate));
try {
// this is a little bit recursive, but this
will use the full default search order for locating
// this.
delegate = (UtilDelegate)Util.loadClass(delegateName,
null, null).newInstance();
} catch (Throwable e) {
org.omg.CORBA.INITIALIZE ex = new
org.omg.CORBA.INITIALIZE("Can not create Util delegate:
"+delegateName);
ex.initCause(e);
throw ex;
}
}
...
According to another code in
ProviderRegistryImpl$SPIRegistry(the id's value is the
delegateName variable as highlighted above), while the
registry hashmap's key is "javax.rmi.CORBA.UtilClass",
that will lead CNF exception.
private synchronized BundleProviderLoader
getLoader(String id) {
// synchronize on the registry instance
if (registry != null) {
log.fine("registry: " + registry);
// return the first match, if any
List<BundleProviderLoader> list =
registry.get(id);
if (list != null && !list.isEmpty()) {
return list.get(0);
}
}
// no match here
return null;
}
So my question is should we change the Util code to pass
the interface class name to load class? Please advise.
I'm not sure I understand the question. The target class in
question here is a concrete delegate instance, so I don't
understand why you think an interface is needed here. The
loading in question here is just for the delegate class that
is used for the rmi util class.
In any event, you cannot change any of the method signatures
for the javax.rmi.CORBA.Util class. That is a standard API
class and you can't add that.
I think I understand what you wish to do here, and I'd
recommend adding a loadServiceClass() method to the
UtilLoader class and change the initializer in Util to use
that directly rather than recursively calling Util.loadClass().
Rick
Forrest
--
Ivan
--
Ivan
