Tapestry Magic #3: Plugin Blocks

Blocks in Tapestry are tools which can be used to overcome the limitations of a static structure. One of the best usage of Blocks is the BeanBlockSource. I have used it in a similar way to create plug-n-play plug-in. I will try to demonstrate it with an example.

Tapestry Magic #4: Integrating Guice

Whenever someone asks me about the difference between Wicket and Tapestry, I have a lot to say but I always conclude with the statement

In Wicket, it is easy to figure-out what to do but difficult to implement whereas in Tapestry, it might be difficult to figure-out what to do but easy to implement

Tapestry Magic #9: Integrating with hibernate and multiple database support

Tapestry5 already has a module for integration with hibernate. This module is restricted to only one database. In this post I will create a small module which can support multiple databases. I am not going to provide all the facilities that tapestry-hibernate module already provides but just enough to solve the multiple database access problem.

Tapestry Magic #10: Integrating With Flying Saucer, Generating PDF

Even Tapestry has limitations!!. One of the limitation is not being able to get hold of the generated response for use, e.g. to send as an email or convert to PDF/Image etc. There are two ways of doing it(atleast Google search results say so). One is to use something like tapx-templating where in you have to create another Tapestry web-instance which can be used for generating content. The second one is to use an HTTP client to get the content from the Tapestry application as suggested by Josh Canfield in this mail.

Tapestry Magic #11: Integration with Jasypt for encrypting URLs

Jasypt is an Java encryption library which can be used for encrypting text, passwords, numbers, binaries etc. We, in this post, will use this library for encrypting Tapestry URLs. Now, why would you want to hide those beautiful tapestry URLs. Imagine a banking website where sensitive information like account numbers are passed as parameters to pages. Won’t it be dangerous to show this information in the browser’s address bar. By encrypting URLs you can hide this information and make your website more secure.

Tapestry Magic #12 : Tapestry IOC aware JSR-303 Custom Validators

In JSR-303, adding a custom field validator is a two step process.

1. Create an annotation which will be placed on a field to be validated
2. Create a validator which implements ConstraintValidator and link it to the above annotation

Integrating Tapestry with Gravatar

Integration with Gravatar‘s avatar is all about embedding an img tag into your page. To create a gravatar image link, the steps involved are :

1. Create a hash from email id
2. Append a type to get image in a particular format. e.g .jpg, .png etc
3. Set query parameters. The currently supported are s(size), d(default), f(force default), r(rating)

Meeting Plastic IV: Replacing interfaces

One of the most common use of class transformation is replacing interfaces by annotations. Earlier j2ee frameworks used to put restrictions on your classes by forcing you to implement a particular interface. Nowadays, modern frameworks just ask you to put an annotation here and there and the rest is handled by the framework. This gives you the freedom of working with pojos.

Meeting Plastic V: A Method Shadow Builder

There are two shadow builders in tapestry, PropertyShadowBuilder(tapestry-ioc) and EnvironmentalShadowBuilder(tapestry-core) . PropertyShadowBuilder is used to create a service from a property of an object(source). It create a proxy for the service interface and then delegates all method calls of that service to the getter method of the source. In this post we will create a more generic shadow builder which will take a source, a method name and a set of parameters and in return create a service that will delegate all method calls to the given source method.

Tapestry Magic #14: Easy Selection

Tapestry’s select component is very flexible and this flexibility comes at a small cost. One has to pass a SelectModel and a ValueEncoder as parameters to the Select component. This seems too much work for simple use cases. With the help of class transformations, we can always find shortcuts. In this post, I will mix some of the useful techniques mentioned in the Wiki to make using Select component easier.

A Simpler Select for Tapestry

After writing my last post, Howard came up with a better idea. Why to stick to only one implementation of Select ? If we need a simpler Select, why not create a simpler one. So, I came with a simple implementation!!

Ajax Upload for Tapestry

Tapestry has an excellent support for JavaScript and Ajax. It strikes a perfect balance between how much a framework should assist and how much the developer should do. Most component-based frameworks, rather than assisting, supervise and most action-based frameworks leave even the integration to the developer. Tapestry provides you with events which you can easily connect to your JavaScript events/functions and all the rest is, as I keep on saying, magic.

In this post, I will talk about integrating an Ajax based upload library, file-uploader with Tapestry.

A Periodic Zone Refresh Mixin for Tapestry

Tapestry uses a concept of Zones for Ajax based updates. Zones are components which are used to identify/mark a portion of a component/page for Ajax updates. Usually zones are connected to client events of other components e.g. click of EventLink or ActionLink component, change event of Select component or submit event of Form component. But what if we just want a zone which refreshes itself with its own contents.This is what we are going to do.

A Modal Dialog For Tapestry

As Tapestry does not provide a Dialog Box, let us see how difficult(or easy) it is to create one on our own. We will use ModalBox as it has an MIT license and it is written in prototype (Soon this won’t be a criteria for choosing a script as Tapestry is going to be prototype independent). The ModalBox script is very easy to use. There is a ModalBox.show() method which displays a dialog box. It takes a dom element and configuration options as parameters. If you want to create a wizard just keep on using the same method inside the dialog box. There is also a ModalBox.hide() method to hide the dialog.

A Tab-panel for Tapestry

Tab panels are used so often in component based web design that many frameworks provide an out-of-box implementation. ChenilleKit has one for Tapestry. Let us try another one.

The tab panel will require two components.

• A TabPanel component to manage the tabs and tab links.
• A Tab component representing a tab

A Tooltip component for Tapestry

I was thinking of adding tooltips using prototip but found a very good free solution in Opentip. This is a very nice library and very easy to integrate. I was able to integrate it with only a single modification to the script and that was to replace the default ajax support with the Tapestry’s own ajax support.

Tapestry & AjaxFormLoop

Tapestry mailing list has a constant flow of newbie questions related to AjaxFormLoop component. This is a very powerful component but with some limitations that must be understood before using it.

AjaxFormLoop allows, in a limited way, dynamic addition of components to a form. These components are laid out inside the AjaxFormLoop. Each time the ‘Add New’ link is clicked, addRow event is triggered. This event requires the event handler to return a new ‘value’ bean. A new row is added to the loop with the given set of components and these components if form fields are bound to the newly instantiated bean.

Tapestry JFreeChart integration

I just finished integrating JFreeChart with Tapestry. Each time you integrate a library with Tapestry you are full of praise for the framework. This is something you can seldom say about other web frameworks.

I had two usages in mind.

1. As a return value from an event handler.
2. As a component which can be used to display JFreeChart and a corresponding imagemap

Tweeting with Tapestry

For tweeting in java, there are not many options like there are in other languages especially ruby. The best solution I have found is scribe-java. Interfacing with this library is very easy but you waste a lot of time trying to find what to do when.

Tapestry Facebook Integration

Continuing from the Tweeting post, lets us extend the OAuth Service to enable us to post on a user’s wall. As all the hard work has already been done, we just have to tweak things a little.

Tapestry 5.3+ : New Features

Tapestry 5.3 is ready for a beta release and there are many exciting features. You can read about them here. The intention of this post and the one following it is to provide some running examples to get you started

Tapestry 5.3+ New Features : Part 2

AjaxResponseRender

This is one of the most useful feature of Tapestry 5.3. There is already a concept of Zone in Tapestry for Ajax but now it is complimented by AjaxResponseRenderer. This fills a lot of gaps at least for people coming from Wicket. It is a bit similar to AjaxRequestTarget but empowered with Zones and JSON. I have compiled a small example demonstrating most of the features.

Tapestry : Using reCaptcha

There is already Captcha support build-in for Tapestry5 but doing something from scratch is always fun in Tapestry. So in this post we are going to use reCaptcha with Tapestry5. There are two ways of integrating reCaptcha in your website. One way is to add it statically and other using Ajax. We are going to use the former case.

Tapestry Linkedin

Continuing from the Tweeting post and Facebook post, lets us extend the OAuth Service to enable us to update status on Linkedin. We start by creating LinkedinService

Tapestry Grid & Hibernate Criteria

Tapestry Grid is a very powerful tool for displaying a list of entities. It expects a GridDataSource as source parameter. A useful tool can be a TypeCoercer which converts a Criteria to GridDataSource.

Tapestry Conquering the World !!

WordPress has added a wonderful way to view blog stats.

This is for the last one year

Tapestry Conquering the World !!

Tapestry hibernate multiple databases

In a recent project, I had a requirement of connecting to multiple databases using hibernate. As tapestry-hibernate module does not provide an out-of-box support, I thought of adding one. https://github.com/tawus/tapestry5

Now that the application is in production, I thought of writing a simple “How to”.

Some Reporting tricks with class-transformations

Every time I used to see some duplication of code, I used to move that code to a new method. With Tapestry, you begin to think differently. Now every time I see duplication, my first thought is “Can I create a worker for it”.

In my current project, I am using a few new ones. So I thought why not share them with you.

Multivalue AutoComplete for Tapestry

I have been very experimenting with tapestry-jquery plugin and it is great to finally go back to jquery. Not only using jquery is very easy but it also comes with a lot of plugins.

There are some improvements that I think can be added to the tapestry-jquery integration but don’t get time to discuss them in the mailing list.

Recently I wanted to use a multivalue autocomplete something on the lines of https://github.com/argoyle/tapestry-tagselect and found a wonderful plugin http://loopj.com/jquery-tokeninput/

Integrating Bootstrap JS with Tapestry5

Adding Bootstrap JS Twispy to your template is very easy

<a href='#' class='twipsy' data-title='My Twipsy'>Hover over me</a>
<script type='text/javascript'>
   $('.twipsy').twipsy();
</a>

and you can always use property-expressions to display some dynamic data. But what if you want to have block rendered as title. This was exactly what I was trying to accomplish in one of my recent projects. (We are using tapestry-jquery for jquery support in that project.)