Multiple method signatures in an MBean

The text formatting seems to be broken on this site. Sorry for the mass of text!
I have an MBean containing some utility functions used within a custom authenticator. At the moment, there all use a single data source, but I need to extend them to use multiple datasources. I also need to maintain backwards compatability with the original system.
I have therefore modififed the xml bean descriptor file and Impl java class by duplicating all the methods, adding a dataSource ID param, as follows:
I started with this method descriptor:
<pre>
<MBeanOperation
Name = "getMaintenanceMode"
ReturnType = "boolean"
Description = "Whatever"
>
<MBeanException>javax.management.MBeanException</MBeanException>
<MBeanException>weblogic.management.utils.NotFoundException</MBeanException>
</MBeanOperation>
</pre>
and impl:
<pre>
public boolean getMaintenanceMode() throws MBeanException , javax.management.MBeanException, weblogic.management.utils.NotFoundException
</pre>
and have now added this :
<pre>
<MBeanOperation
Name = "getMaintenanceMode"
ReturnType = "boolean"
Description = "Whatever"
>
<MBeanOperationArg Name = "dataSourceId" Type = "int"
Description = "Data Source ID"
/>
<MBeanException>javax.management.MBeanException</MBeanException>
<MBeanException>weblogic.management.utils.NotFoundException</MBeanException>
</MBeanOperation>
</pre>
and
<pre>
public boolean getMaintenanceMode(int dataSourceId) throws MBeanException , javax.management.MBeanException, weblogic.management.utils.NotFoundException
</pre>
With these code changes in place, the MBean builds correctly, using the MBeanMaker, however WLS(814) falls over on startup with the exception:
<pre>
javax.management.JMRuntimeException: Two operations with the same name, "getMaintenanceMode", in MBean type: com.aol.universal.security.tools.DashboardUserTools
at weblogic.management.commo.ModelMBeanTypeMBean.getExpandedMBeanInstanceInfo(ModelMBeanTypeMBean.java:1092)
at weblogic.management.commo.ModelMBeanTypeMBean.<init>(ModelMBeanTypeMBean.java:250)
at sun.reflect.GeneratedConstructorAccessor3.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:274)
at com.sun.management.jmx.MBeanServerImpl.internal_instantiate(MBeanServerImpl.java:2232)
at com.sun.management.jmx.MBeanServerImpl.createMBean(MBeanServerImpl.java:763)
at weblogic.management.internal.RemoteMBeanServerImpl.createMBean(RemoteMBeanServerImpl.java:897)
at javax.management.loading.MLet.getMBeansFromURL(MLet.java:542)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at com.sun.management.jmx.MBeanServerImpl.invoke(MBeanServerImpl.java:1633)
at com.sun.management.jmx.MBeanServerImpl.invoke(MBeanServerImpl.java:1528)
at weblogic.management.internal.RemoteMBeanServerImpl.private_invoke(RemoteMBeanServerImpl.java:988)
at weblogic.management.internal.RemoteMBeanServerImpl.invoke(RemoteMBeanServerImpl.java:946)
at weblogic.management.commo.Commo.initTypesAtLocation(Commo.java:1409)
at weblogic.management.commo.Commo.initTypes(Commo.java:552)
at weblogic.management.commo.Commo.initTypes(Commo.java:534)
at weblogic.management.AdminServerAdmin.initializeCommo(AdminServerAdmin.java:656)
at weblogic.management.AdminServerAdmin.initializeRepository(AdminServerAdmin.java:874)
at weblogic.management.AdminServerAdmin.initialize(AdminServerAdmin.java:267)
at weblogic.t3.srvr.T3Srvr.initializeHere(T3Srvr.java:771)
at weblogic.t3.srvr.T3Srvr.initialize(T3Srvr.java:670)
at weblogic.t3.srvr.T3Srvr.run(T3Srvr.java:344)
at weblogic.Server.main(Server.java:32)
</pre>
Granted there <i>are</i> two methods with the same name, but they have different signatures, so they are <i>different</i> methods! Its just simple OO method overloading, after all!
Has anyone run into this in, too? Is there a solution?
cheers
Paul

Hi,
I doubt that the addition of a second signature actually invalidates (the red X icon) the first signature, but rather it shows the signature as Valid with Changes (the pen & yellow triangle icon). Technically, that is the correct signature status, but because it caused so much confusion, beginning with version 9, we've changed the user interface and stopped indicating changes to the PDF if the only change is a subsequent signature.
If on the other hand you are getting the red X for the first signature please let me know as I'd be curious to see the file.
Steve

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// --------------- Modification History --------------------------
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Yuthura

Yuthura wrote:
I know it may throw any checked exception, but I'm pretty certain that an interface that extends java.rmi.Remote must include at least java.rmi.RemoteException in its throws clause (unless the spec has changed in Java 1.5/1.6).No.
A method can always throw fewer exceptions than the one it's overriding. RMI has nothing to do with it.
See Deitel & Deilte Advanced Java 2 Platform How To Program, 1st Ed. (ISBN 0-13-089650-1), page 793 (sorry, I couldn't find the RMI spec quick enough). Quote: "Each method in a Remote interface must have a throws clause that indicates that the method can throw RemoteException".Which means that there's always a possibility of RemoteException being thrown. That's a different issue. It's not becusae the parent class can throw RE. Rather, it's because some step that will always be followed is declared to throw RE.
I later also noticed I could not add other checked exceptions, which made sense indeed. Your explanation made perfect sense now that I heard (read) it. But just to humour my curousity, has this always been possible? Yes, Java has always worked that way.
PS: The overwriting/-riding was a grammatical typo (English is not my native language), but I meant to say what you said.No problem. Minor detail. It's a common mistake, but I always try to encourage proper terminology.

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