I try making a patch for this problem, pls review. thanks!
Forrest
On Tue, Jan 11, 2011 at 10:39 PM, Rick McGuire <[email protected]> wrote:
> On 1/11/2011 9:20 AM, Ivan wrote:
>
>>
>> Hmm, I have to say that I know little about corba, just from the codes of
>> UtilLoader.loadClass, the first part of that method is trying to load an
>> implementation of the SPI, but the left part is just to load the SPI itself,
>> is it the expected behavior ?
>>
> Util.loadClass() is used for a lot more purposes than loading an SPI. The
> problem is occurring because the code is overloading the concepts on to the
> single loadClass() method. What is needed to fix this problem is a solution
> specific to the task of loading an SPI.
>
> Rick
>
>
> If we need to look up a specific provider for an interface, maybe it is
>> better to use the similar method suggested by you. which passing both the
>> SPI and defaultImpl class, then we might first try to look up the impl by
>> ProviderLocator, if failed, try to load the default impl by context
>> classloader or stack classloader...
>> Thanks.
>>
>> 2011/1/11 Rick McGuire <[email protected] <mailto:[email protected]>>
>>
>> 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 <[email protected]
>> <mailto:[email protected]> <mailto:[email protected]
>>
>> <mailto:[email protected]>>>
>>
>>
>> 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 <[email protected]
>> <mailto:[email protected]> <mailto:[email protected]
>>
>> <mailto:[email protected]>>>
>>
>>
>> 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
>>
>>
>>
>>
>>
>> --
>> Ivan
>>
>
>
Index: yoko-rmi-impl/src/main/resources/OSGI-INF/blueprint/provider.xml
===================================================================
--- yoko-rmi-impl/src/main/resources/OSGI-INF/blueprint/provider.xml (revision 1058129)
+++ yoko-rmi-impl/src/main/resources/OSGI-INF/blueprint/provider.xml (working copy)
@@ -35,12 +35,12 @@
destroy-method="stop"
activation="eager"/>
- <bean class="org.apache.yoko.osgi.locator.ProviderBean"
+ <bean class="org.apache.yoko.osgi.locator.ServiceBean"
activation="eager"
init-method="start"
destroy-method="stop">
<argument>
- <value>javax.rmi.CORBA.UtilClass</value>
+ <value>javax.rmi.CORBA.UtilDelegate</value>
</argument>
<argument>
<value>org.apache.yoko.rmi.impl.UtilImpl</value>
@@ -57,7 +57,7 @@
init-method="start"
destroy-method="stop">
<argument>
- <value>javax.rmi.CORBA.PortableRemoteObjectClass</value>
+ <value>javax.rmi.CORBA.PortableRemoteObjectDelegate</value>
</argument>
<argument>
<value>org.apache.yoko.rmi.impl.PortableRemoteObjectImpl</value>
@@ -74,7 +74,7 @@
init-method="start"
destroy-method="stop">
<argument>
- <value>org.apache.yoko.rmi.PortableRemoteObjectExtClass</value>
+ <value>org.apache.yoko.rmi.api.PortableRemoteObjectExtDelegate</value>
</argument>
<argument>
<value>org.apache.yoko.rmi.impl.PortableRemoteObjectExtImpl</value>
@@ -91,7 +91,7 @@
init-method="start"
destroy-method="stop">
<argument>
- <value>javax.rmi.CORBA.StubClass</value>
+ <value>javax.rmi.CORBA.StubDelegate</value>
</argument>
<argument>
<value>org.apache.yoko.rmi.impl.StubImpl</value>
Index: yoko-rmi-spec/src/main/java/org/apache/yoko/rmispec/util/UtilLoader.java
===================================================================
--- yoko-rmi-spec/src/main/java/org/apache/yoko/rmispec/util/UtilLoader.java (revision 1058129)
+++ yoko-rmi-spec/src/main/java/org/apache/yoko/rmispec/util/UtilLoader.java (working copy)
@@ -36,10 +36,21 @@
// since that method will call loadClass0 which uses this field... if it is below the static
// initializer the _secman field will be null
private static final SecMan _secman = getSecMan();
+
+ static public Class<?> loadServiceClass(String delegateName, Class<?> iface) throws ClassNotFoundException {
+
+ try {
+ return ProviderLocator.getServiceClass(iface.getName(), null, null);
+ } catch (ClassNotFoundException e){
+ // skip
+ }
+
+ return loadClass0(delegateName, null, null);
+ }
static public Class loadClass(String name, String codebase, ClassLoader loader)
throws ClassNotFoundException {
- Class result = null;
+
try {
return ProviderLocator.loadClass(name, null, loader);
@@ -47,7 +58,14 @@
//skip
}
- ClassLoader stackLoader = null;
+ return loadClass0(name, codebase, loader);
+ }
+
+ private static Class<?> loadClass0(String name, String codebase, ClassLoader loader)
+ throws ClassNotFoundException {
+ Class result = null;
+
+ ClassLoader stackLoader = null;
ClassLoader thisLoader = UtilLoader.class.getClassLoader();
Class[] stack = _secman.getClassContext();
for (int i = 1; i < stack.length; i++) {
Index: yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Stub.java
===================================================================
--- yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Stub.java (revision 1058129)
+++ yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Stub.java (working copy)
@@ -25,6 +25,7 @@
import java.security.AccessController;
import org.apache.yoko.rmispec.util.GetSystemPropertyAction;
+import org.apache.yoko.rmispec.util.UtilLoader;
import org.omg.CORBA.ORB;
import org.omg.CORBA_2_3.portable.ObjectImpl;
@@ -40,7 +41,8 @@
// Initialize delegate
String delegateName = (String)AccessController.doPrivileged(new GetSystemPropertyAction("javax.rmi.CORBA.StubClass", defaultDelegate));
try {
- delegateClass = Util.loadClass(delegateName, null, null);
+ //delegateClass = Util.loadClass(delegateName, null, null);
+ delegateClass = UtilLoader.loadServiceClass(delegateName, StubDelegate.class);
} catch (Exception e) {
org.omg.CORBA.INITIALIZE ex = new org.omg.CORBA.INITIALIZE("Can not create Stub delegate: " + delegateName);
ex.initCause(e);
Index: yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Util.java
===================================================================
--- yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Util.java (revision 1058129)
+++ yoko-rmi-spec/src/main/java/javax/rmi/CORBA/Util.java (working copy)
@@ -43,7 +43,8 @@
// 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();
+ //delegate = (UtilDelegate)Util.loadClass(delegateName, null, null).newInstance();
+ delegate = (UtilDelegate)UtilLoader.loadServiceClass(delegateName, UtilDelegate.class).newInstance();
} catch (Throwable e) {
org.omg.CORBA.INITIALIZE ex = new org.omg.CORBA.INITIALIZE("Can not create Util delegate: "+delegateName);
ex.initCause(e);
