不了解JSF.以下内容来自网上:(说的有点那个,JSF作为标准和.Net WebForms叫板的东西应该也是很有....) -------------------------- JSF is a set of APIs, wrapped by Taglibs, for use (mostly) in JSP pages.JSF claims to be a component framework, but its JSP and Taglib roots are simply dragging it back and preventing it from really achieving its goals.Here is just _one_ example -- defining components.In order to define a new component in Tapestry you need to do:1. Declare the component specification (parameters, etc) in a .JWC file 2. Create the component template and save it into a .HTML file 3. [optional] Write the component logic into a Java Bean 4. [optional] Declare the component in the application or in a libraryAlso, the UI of the component is defined in a template that is easy to understand and modify by a web designer or another developer; components and pages are pretty much the same -- there is little fundamental difference between the two -- the concepts that a developer has to deal are just a single set. In contrast, here is the procedure you must follow to define a new JSF component according to the JSF tutorial:----------------------8<------------------------- 1. Write a tag handler class that extends javax.faces.webapp.FacesTag. In this class, you need: . A getRendererType method, which returns the type of your custom renderer, if you are using one (explained in step 4). . A getComponentType method, which returns the type of the custom component. . An overrideProperties method, in which you set all of the new attributes of your component.2. Create a tag library descriptor (TLD) that defines the custom tag.3. Create a custom component class4. Include the rendering code in the component class or delegate it to a renderer (explained in step 6).5. If your component generates events, queue the event on the FacesContext.6. Delegate rendering to a renderer if your component does not handle the rendering. a. Create a custom renderer class by extending javax.faces.render.Renderer. b. Register the renderer to a render kit. c. Identify the renderer type in the component tag handler.7. Register the component8. Create an event handler if your component generates events.9. Declare your new TLD in your JSP page and use the tag in the page. ---------------------->8-------------------------In addition, the UI of new components is defined very differently and is much more dificult to understand than the UI of JSP pages. Typically this is done in the Java code itself -- there has been no effort to make the code/HTML separation as in Tapestry.Given all this, I can only conclude that JSF essentially _discourages_ developers from building his own components, and instead use standard ones provided by a "guru" who has time and can expend the effort to do and test all of the above.Writing components-based apps for JSF is like writing OO code in C -- it is certainly possible, but it is much more difficult than doing it by using a language designed for that purpose. Just to conclude -- there is a big _conceptual_ difference between the two frameworks in general:Tapestry was built from the ground up with a specific philosophy in mind -- "objects, methods, properties" rather than strings and URLs, and if I may add, "simplicity, modularity, scalability" rather than a complex political marriage of different technologies. During the design of Tapestry Howard has not been afraid to throw away what does not work and utilize only ideas that make life for developers easier.On the other hand JSF constitutes a blank refusal to let go of legacy technologies that are limited in scope, have proved problematic in large-sclae development, and instead come up with something new and effective. It simply piles up complexity on top of the existing approaches and refuses to acknowledge the errors of the past. At the end, tools may compensate a little for the complexity of JSF development, but they simply cannot resolve the fundamental issues. Frankly, I am quite disappointed with JSF -- it will probably cause more problems than it will resolve. It could have been a far better framework if it had not voluntarily taken upon the above design limitations. Pity that Sun will try to ram it down everybody's throat, but it is questionable how much people can take if it is their productivity that suffers.
--------------------------
JSF is a set of APIs, wrapped by Taglibs, for use (mostly) in JSP pages.JSF claims to be a component framework, but its JSP and Taglib roots are
simply dragging it back and preventing it from really achieving its goals.Here is just _one_ example -- defining components.In order to define a new component in Tapestry you need to do:1. Declare the component specification (parameters, etc) in a .JWC file
2. Create the component template and save it into a .HTML file
3. [optional] Write the component logic into a Java Bean
4. [optional] Declare the component in the application or in a libraryAlso, the UI of the component is defined in a template that is easy to
understand and modify by a web designer or another developer; components and
pages are pretty much the same -- there is little fundamental difference
between the two -- the concepts that a developer has to deal are just a
single set.
In contrast, here is the procedure you must follow to define a new JSF
component according to the JSF tutorial:----------------------8<-------------------------
1. Write a tag handler class that extends javax.faces.webapp.FacesTag. In
this class, you need:
. A getRendererType method, which returns the type of your custom
renderer, if you are using one (explained in step 4).
. A getComponentType method, which returns the type of the custom
component.
. An overrideProperties method, in which you set all of the new
attributes of your component.2. Create a tag library descriptor (TLD) that defines the custom tag.3. Create a custom component class4. Include the rendering code in the component class or delegate it to a
renderer (explained in step 6).5. If your component generates events, queue the event on the FacesContext.6. Delegate rendering to a renderer if your component does not handle the
rendering.
a. Create a custom renderer class by extending
javax.faces.render.Renderer.
b. Register the renderer to a render kit.
c. Identify the renderer type in the component tag handler.7. Register the component8. Create an event handler if your component generates events.9. Declare your new TLD in your JSP page and use the tag in the page.
---------------------->8-------------------------In addition, the UI of new components is defined very differently and is
much more dificult to understand than the UI of JSP pages. Typically this is
done in the Java code itself -- there has been no effort to make the
code/HTML separation as in Tapestry.Given all this, I can only conclude that JSF essentially _discourages_
developers from building his own components, and instead use standard ones
provided by a "guru" who has time and can expend the effort to do and test
all of the above.Writing components-based apps for JSF is like writing OO code in C -- it is
certainly possible, but it is much more difficult than doing it by using a
language designed for that purpose.
Just to conclude -- there is a big _conceptual_ difference between the two
frameworks in general:Tapestry was built from the ground up with a specific philosophy in mind --
"objects, methods, properties" rather than strings and URLs, and if I may
add, "simplicity, modularity, scalability" rather than a complex political
marriage of different technologies. During the design of Tapestry Howard has
not been afraid to throw away what does not work and utilize only ideas that
make life for developers easier.On the other hand JSF constitutes a blank refusal to let go of legacy
technologies that are limited in scope, have proved problematic in
large-sclae development, and instead come up with something new and
effective. It simply piles up complexity on top of the existing approaches
and refuses to acknowledge the errors of the past. At the end, tools may
compensate a little for the complexity of JSF development, but they simply
cannot resolve the fundamental issues.
Frankly, I am quite disappointed with JSF -- it will probably cause more
problems than it will resolve. It could have been a far better framework if
it had not voluntarily taken upon the above design limitations. Pity that
Sun will try to ram it down everybody's throat, but it is questionable how
much people can take if it is their productivity that suffers.
还不能利用JUnit等,在TDD叫的那么火的情况下,这是需要考虑的.那位大虾有经验的,欢迎也很希望能共享一下.谢谢!
现在我是每改动一点点东西都得redeploy.....只有不断学习了..不过现在的人气不是很高.
官方现在有个论坛,人气不是一般的低啊.