Contribute to NetBeans (and other projects)

You may support open source projects by contributing comments, bug reports, wish lists or code etc.

For the current release of NetBeans, I only reported some bugs. This is a partial result of these contributions: Continue reading “Contribute to NetBeans (and other projects)”

JSF, mark required fields

Don’t you know this: You have an application using some dialogs and each dialog contains some required fields and some, whiche are not mandatory. To disinguish these two kinds of fields, the required fields should be marked, e.g. with an asterisk. Now, what we want to do, is to write a central function which might be used in all pages. The idea is quite simple: Before rendereing, check all labels and theis associated input components. If the input is required, mark it. Continue reading “JSF, mark required fields”

Tutorial web development (with JSF) VI: Templates


In the last part of this series, we created a second page, which looked similar to the first one. Now, we will put the common parts into a central place. To do this, we’ll create a template, which acts as kind of container for the shared part, which contains some individual information.

As a reminder, here is the souce of tese two pages:

Continue reading “Tutorial web development (with JSF) VI: Templates”

JPA and legacy database

Suppose, you have to store orders in a SQL DBMS. An order consists of header (address, date, number etc.) as well as a variable count oflines (amount, product, price, tax, …). This should be stored in two tables.

Table Order (
        orId Integer,

Table OrderLine (
        olId Integer,
        olOrderId Integer,

To prevent working directy with SQL, you use JPA. Two entity classes, which are annoted.

Continue reading “JPA and legacy database”

Tutorial web development (with JSF) V: Scene change

Scene change

The tiny calculator is now functional. After entering the two parameters ans clicking on one of the buttons for the basic arthimetics, you’ll get the result just below the buttons. This is well designed since the usuer usually wants to stay on this site and continues calculating. On the other side, lots of apps exists with quite a couple of pages. For example, think about a booking system or a shop. Finishing a transaction you’ll usually get es confirmation page. I like to demonstrate you something similar: The result od the addition will be presented on a different page. A button “back” leads you back to the calculator’s main page. This is not a very user friendly design, but it’s just to show you a first approach of page nagvigation.

Continue reading “Tutorial web development (with JSF) V: Scene change”