No such class at run--time?

Hi there.
I'm trying locate the following constructor at run=time:
package cliquespace.core.agentdevice.cliquespace.agent.device.spine;
final public class AgentDeviceActiveAffiliation extends DeviceActiveAffiliation<AgentDeviceActiveAffiliationPrecis,AgentDeviceMediaProfile,
AgentDeviceConnection,AgentDeviceActiveAffiliation>{
    public AgentDeviceActiveAffiliation(SourceCliqueSpace sourceCliqueSpace,LimitingConstraint[]limitingConstraints,
        AgentDeviceActiveAffiliationPrecis precis)throws CliqueSpaceException{
        super(sourceCliqueSpace,limitingConstraints,precis);
    }Note that DeviceActiveAffiliation extends SourceActiveAffiliation.
I use the following code to do this:
214    public SourceCliqueSpaceElement createElementFromPrecis(SourceCliqueSpace cliqueSpace,SourceCliqueSpaceElementPrecis precis)
215     throws CliqueSpaceException{
216        /**
217         * Get the Element's class.
218         */
219        Class cl=null;
220        try{
221            cl=Class.forName(precis.getElementCanonicaName());
222        }catch(ClassNotFoundException cnfe){
223            ReceiveElementGivenCanonicalTypeHasNoSourceCliqueSpaceElement x=
224             new ReceiveElementGivenCanonicalTypeHasNoSourceCliqueSpaceElement(precis.getIdentifier(),precis.getElementCanonicaName());
225            x.initCause(cnfe);
226            throw x;
227        }
228
229        /**
230         * Get the class's precis constructor.
231         */
232        Class[]paa=new Class[3];
233        if(precis.getCliqueSpaceType().equals(AgentCollaborationCliqueSpace.class.getSimpleName())){
234            paa[0]=AgentCollaborationCliqueSpace.class;
235        }else if(precis.getCliqueSpaceType().equals(AgentDeviceCliqueSpace.class.getSimpleName())){
236            paa[0]=AgentDeviceCliqueSpace.class;
237        }else{
238            throw new CreateElementFromPrecisCliqueSpaceTypeIsUnknown(this.getName(),precis.getCliqueSpaceName(),precis.getCliqueSpaceType());
239        }
240        paa[1]=LimitingConstraint[].class;
241        paa[2]=precis.getClass();
242        Constructor co=null;
243        try{
244            co=cl.getConstructor(paa);
245        }catch(NoSuchMethodException nsme){
246            ReceiveElementNoPrecisConstructorExistsForSourceCliqueSpaceElement x=
247             new ReceiveElementNoPrecisConstructorExistsForSourceCliqueSpaceElement(precis.getIdentifier(),precis.getElementCanonicaName());
248            x.initCause(nsme);
249            throw x;
250        }
276    }[/code.
However, when the code runs, I get the following exception:cliquespace.core.exception.agentdevice.agentdevice.ReceiveElementNoPrecisConstructorExistsForSourceCliqueSpaceElement: An Element identified by [9DNCEJ0AVQVJLJEHP00EKTKKJWMXB77U2C9XCZAQ] of type [cliquespace.core.agentdevice.cliquespace.agent.device.spine.AgentDeviceActiveAffiliation] cannot be constructed from a received precis because the given class has no precis constructor.
Caused by: java.lang.NoSuchMethodException: cliquespace.core.agentdevice.cliquespace.agent.device.spine.AgentDeviceActiveAffiliation.<init>(cliquespace.core.agentdevice.cliquespace.AgentCollaborationCliqueSpace, [Lcliquespace.core.cliquespace.constraint.LimitingConstraint;, cliquespace.core.agentdevice.cliquespace.agent.device.spine.activeaffiliation.AgentDeviceActiveAffiliationPrecis)
        at java.lang.Class.getConstructor0(Class.java:2723)
        at java.lang.Class.getConstructor(Class.java:1674)
        at cliquespace.core.agentdevice.AgentDevice.createElementFromPrecis(AgentDevice.java:244)
        at cliquespace.core.agentdevice.AgentDevice.receiveElement(AgentDevice.java:346)
        at cliquespace.core.agentdevice.AgentDevice.receiveElement(AgentDevice.java:64)
...[/code]
Note, AgentCollaborationCliqueSpace also extends SourceCliqueSpace. So, specifying either AgentCollaborationCliqueSpace or AgentDeviceCliqueSpace should yield the given constructor.
As far as I can determine, the other parameters line up.
It's got me stumped. Your advice, suggestions and/or, help would be appreciated.
Thanks,
Owen.

One needs to use the class declared in the parameter, even, as SourceCiqueSpace is in this case, if the class is abstract.

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