alma.demo.XmlComponentImpl

Class XmlComponentHelper

java.lang.Object

alma.acs.container.ComponentHelper

alma.demo.XmlComponentImpl.XmlComponentHelper

public class XmlComponentHelper
extends ComponentHelper

Helper class for the XmlContainer component.

XmlContainer implements an "inner" functional interface that is different from the IDL generated XmlComponentOperations. It uses xml binding classes instead of stringified xml in the method signatures. An interface translator is created that translates between the flat-xml in the outer (CORBA) interface and the transparent-xml binding classes in the inner interface.

Author:

hsommer Nov 29, 2002 3:37:24 PM

Field Summary

Fields inherited from class alma.acs.container.ComponentHelper

componentInstanceName

Constructor Summary

Constructors

Constructor and Description
XmlComponentHelper(java.util.logging.Logger containerLogger)

Method Summary

Modifier and Type	Method and Description
protected ComponentLifecycle	_createComponentImpl() Method _createComponentImpl to be provided by subclasses.
protected java.lang.String[]	_getComponentMethodsExcludedFromInvocationLogging() Tells the container to not automatically log calls to certain component interface methods.
protected java.lang.Object	_getInterfaceTranslator(java.lang.Object defaultInterfaceTranslator) To be overridden by subclass only if it wants its own interface translator to be used.
protected java.lang.Class<? extends ACSComponentOperations>	_getOperationsInterface() Gets the xxOperations interface as generated by the IDL compiler.
protected java.lang.Class<? extends org.omg.PortableServer.Servant>	_getPOATieClass() This method must be provided by the component helper class.
protected java.lang.Class<?>	getInternalInterface() Gets the component's implemented functional IF.

Methods inherited from class alma.acs.container.ComponentHelper

getComponentImpl, getComponentLogger, getOperationsInterface, requiresOrbCentralLogSuppression

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

XmlComponentHelper

public XmlComponentHelper(java.util.logging.Logger containerLogger)

Parameters:

containerLogger -

Method Detail

_createComponentImpl

protected ComponentLifecycle _createComponentImpl()

Description copied from class: ComponentHelper

Method _createComponentImpl to be provided by subclasses. Must return the same object that also implements the functional component interface.

Specified by:

_createComponentImpl in class ComponentHelper

Returns:

ComponentLifecycle The component impl class that implements the ComponentLifecycle interface.

See Also:

ComponentHelper._createComponentImpl()

_getPOATieClass

protected java.lang.Class<? extends org.omg.PortableServer.Servant> _getPOATieClass()

Description copied from class: ComponentHelper

This method must be provided by the component helper class. It must return the Class of the IDL-generated POA-Tie Servant, as in
return DummyComponentPOATie.class;.

Specified by:

_getPOATieClass in class ComponentHelper

See Also:

ComponentHelper._getPOATieClass()

_getOperationsInterface

protected java.lang.Class<? extends ACSComponentOperations> _getOperationsInterface()

Description copied from class: ComponentHelper

Gets the xxOperations interface as generated by the IDL compiler. This method must be provided by the component helper class.

Specified by:

_getOperationsInterface in class ComponentHelper

Returns:

the Class object associated with the operations interface.

See Also:

ComponentHelper._getOperationsInterface()

getInternalInterface

protected java.lang.Class<?> getInternalInterface()

Description copied from class: ComponentHelper

Gets the component's implemented functional IF. For instance, the method signatures can be the same as in the operations interface, except that the internal interface uses xml binding classes where the IDL-generated operations interface only contains stringified XML.

To be overridden by the component helper class only if the InternalInterface differs from the OperationsInterface.

Overrides:

getInternalInterface in class ComponentHelper

Returns:

Class the Java Class of the internal interface.

See Also:

ComponentHelper.getInternalInterface()

_getInterfaceTranslator

protected java.lang.Object _getInterfaceTranslator(java.lang.Object defaultInterfaceTranslator)
                                            throws AcsJJavaComponentHelperEx

Description copied from class: ComponentHelper

To be overridden by subclass only if it wants its own interface translator to be used.

The returned interface translator must implement the component's operations interface, and must take care of translating in, inout parameters, forwarding the call to the respective method in the component implementation, and then translating out, inout parameters, and the return value.

It is foreseen that the necessary translations for most methods will be done automatically by the dynamic proxy classes. Some methods may require manual translation, e.g. if an expression that involves xml entity classes is too complex for the dynamic proxy.
On the other end of the spectrum, a manual implementation may choose to not unmarshal a marshalled binding object that it receives as an in parameter, because the binding object will only be routed through to another component, so first unmarshalling and later marshalling it would be an unnecessary performance loss. In that case, the manual interface translator could call an additional method in the component implementation which expects the marshalled xml rather than the binding object.

To facilitate the implementation of a manual interface translator, the defaultInterfaceTranslator is provided; it is a dynamic proxy object that implements the component's operations interface and forwards all calls to the component implementation created in _createComponentImpl, performing type translations in between. The methods that should be handled automatically can then be directly delegated to that proxy object, and only those methods that require special care need to be implemented by hand.

Overrides:

_getInterfaceTranslator in class ComponentHelper

Parameters:

defaultInterfaceTranslator - the default translator that the custon translator may use to delegate some or all method invocations to.

Returns:

the custom translator, or null if the default translator should be used.

Throws:

AcsJJavaComponentHelperEx

See Also:

ComponentHelper._getInterfaceTranslator(java.lang.Object)

_getComponentMethodsExcludedFromInvocationLogging

protected java.lang.String[] _getComponentMethodsExcludedFromInvocationLogging()

Description copied from class: ComponentHelper

Tells the container to not automatically log calls to certain component interface methods. This method may be overridden by helper subclasses, since the default behavior is for the container to log all component method invocations except ACSComponentOperations#componentState().

Dealing with OffShoots: offshoots that follow the Corba Tie-approach enjoy automatic method invocation logging just like components do. In the rare event that you explicitly activate offshoots from your component, and want to suppress automatic logging for certain methods, return String(s) in the following format: OFFSHOOT::<offshootinterfacename>#<methodname>. Example for ALMA archive: "OFFSHOOT::Operational#retrieveFragment".

Note that returning Strings is fine (compared with more sophisticated Method objects) because the functional component interface methods cannot have parameter polymorphism thanks to IDL limitations. Thus there is no ambiguity in the method names.

Overrides:

_getComponentMethodsExcludedFromInvocationLogging in class ComponentHelper

Returns:

names of component methods for which the call-intercepting container should not log anything. Can be null.