Simon,

For part 1), are you proposing that we stop overriding getAttributes()? If so, private implementation properties used by the component and set by using setAttribtue(), would not be available on the FacesBean. So I assume that you are suggesting that we change the components to set these on the FacesBean directly in these cases.

I did a quick grep and the components and they are using the attributeMap. It is unclear how many of these would be left if we removed all of the cases where the direct accessor could be used, and the cases where we would switch to direct FacesBean access, however these case do suffer from the worst of all worlds as far as performance, since the pay the cost of both reflection and Map access.

-- Blake Sullivan


Simon Lessard said the following On 1/5/2010 12:32 PM PT:
Hi Blake,

Actually it's harsher/simpler than that. Assuming that .getAttributes() is
very rarely used in a Trinidad application (exception for custom
attributes).

1. Have AttributeMap work exactly like standard JSF's AttributeMap. That is,
always call the getter/setter on the component (which in turn will use the
FacesBean if needed). For custom properties, they could either be stored in
the FacesBean or on the component itself
2. Handle the id attribute manually for state saving purposes in
UIXComponentBase

Point 1. does impact performances vs. direct FacesBean access when accessing
defined properties, but all Trinidad applications most likely directly use
FacesBean.getProperty(PropertyKey) directly, like all our renderer do. For
custom properties, there's absolutely no hit.


Regards,

~ Simon

On Tue, Jan 5, 2010 at 3:24 PM, Blake Sullivan <[email protected]>wrote:

 Is your suggestion that we
1) Add a new Map(String, Object>) implementation that takes both the
FacesBean and the UIComponent
2) Explicitly test for the id attribute in all of the accessor and mutator
functions, in addition to the the Sets returned
3) Override the state saving/restoration  code to explicitly handle id

-- Blake Sullivan

Simon Lessard said the following On 1/5/2010 12:08 PM PT:

Have the AttributeMap call the getId/setId. The contract for the Map
returned by getAttributes is supposed to call the getter/setter method on
the component anyway, 
fromhttp://java.sun.com/javaee/5/docs/api/javax/faces/component/UIComponent.html#getAttributes%28%29
:




    - get() - If the property is readable, call the getter method and
   return the returned value (wrapping primitive values in their corresponding
   wrapper classes); otherwise throw IllegalArgumentException.
   - put() - If the property is writeable, call the setter method to set
   the corresponding value (unwrapping primitive values in their corresponding
   wrapper classes). If the property is not writeable, or an attempt is made to
   set a property of primitive type to null, throw
   IllegalArgumentException.




 Regards,

~ Simon


On Tue, Jan 5, 2010 at 2:50 PM, Blake Sullivan <[email protected]> 
<[email protected]>wrote:



  The reason is that we need to support AttributeMap/component accessor
equivalence--get/set of the id attribute through the Map is supposed to work
correctly.  The ValueExpression only exists to make this work.

-- Blake Sullivan

Simon Lessard said the following On 1/5/2010 10:57 AM PT:

Hi,

Why not simply NOT support a PropertyKey for the id attribute? I know it
isn't consistent with the other properties, but id is a very special case
not supporting EL anyway. In all the project I ever did, I never used
FacesBean.getProperty(ID_
PROPERTY_KEY). The only drawback I would see is if
the component's id actually need to be read in a property getter method in a
renderer which receive only the FacesBean instance and not the component
itself. That would be much faster than a custom ValueExpression and the
memory footprint would also be better.

Regards,

~ Simon

On Tue, Jan 5, 2010 at 1:49 PM, Matthias Wessendorf <[email protected]> <[email protected]> 
<[email protected]> <[email protected]>wrote:



 On Thu, Dec 31, 2009 at 11:12 PM, Blake Sullivan<[email protected]> 
<[email protected]> <[email protected]> <[email protected]> 
wrote:


 UIComponent.getId() is by far the most requested component attribute.


  There


 are a number of reasons for this:
1) The JSF RI has an issue in the JSP-JSF integration which causes


 getId()


 to be called n^2 times where n is the number of children a component has


 I guess this is true for MyFaces as well, right?



 2) getClientId() calls getId()
3) FindComponent calls getId()
4) The tree visiting code trades off calls to getClientId() for calls to
getId()

FacesBean optimizes attribute Map access at the expense of access


 directly


 through the component.  The the extent that Renderers are Components are
accessing the attributes through the attribute Map, this is fine, however
even the Renderers access attributes common to all UIComponents such as


 id()


 through the component directly.  Considering the huge number of times


 that


 the the id is accessed (for some renders, this was 8% of the rendering
time), it makes sense to optimize this path.

The proposal is to:
1) Store the id an an instance variable on the UIXComponent
2) Add a new capability flag to PropertyKey indicating that the property


 is


 actually stored elsewhere using a ValueExpression will be stored as the
property's value in the PropertyMap.  For access through the FacesBean,


 the


 ValueExpression will be evaluated to get/set the actual value
3) For state saving the ValueExpression is used to retrieve the actual


 value


 and for state restoration the ValueExpression (which has been


 rebootstrapped


 by the UIXComponent) is used to write the value back
4) Instead of setting the id attribute in the FacesBean, UIXComponent


 stores


 it locally and sets an ValueExpression implementation into the FacesBean
that retrieves the value from the UIXComponent


 +1 on api/patch



 API Changes:

PropertyKey:

add

 /**
 * Capability indicating that values for this property should be
 * be stored and retrieved through a ValueExpression rather than on the
 * FacesBean itself
 */
 static public final int CAP_VALUE_EXPRESSION_IMPLEMENTATION = 16;

 /**
 * Returns <code>true</code> if property values for this key are set and


 get


  * using a ValueExpression rather than storing the value in the


 FacesBean.


  * @return <code>true</code> if properties values for this key are


 retrieved


  * with a ValueExpression.
 */
 public boolean usesValueExpressionAsImplementation()

After this change id retrieval doesn't make the 1% YourKit profiler hot


 spot


 cut off





 --
Matthias Wessendorf

blog: http://matthiaswessendorf.wordpress.com/

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