Recently I had to choose a validation framework or write one by my own. First I thought, no big deal, validation is not that a complicated issue. But the more you think of it, the more you come to the conclusion it is not as shallow as you think – you need to validate different types, you have different groups and much more issues… In short, writing a validation framework by yourself demands a lot of work. Luckily, JSR 303 comes to solve exactly that and the hibernate implementation of this JSR does a pretty good job. Hibernate Validator is a JSR 303 implementation for bean validation. The way to work with this framework is first, to define constraints for a java bean fields, and then, validating the bean. JSR 303 JSR 303 – defines a metadata model and API for entity validation. The default metadata source is annotations, with the ability to override and extend the meta-data through the use of XML. The API is not tied to a specific application tier or programming model. It is specifically not tied to either the web tier or the persistence tier, and is available for both server-side application programming, as well Continue reading Using Hibernate Validator to cover your validation needs
EasyImage lets you do all the basic image operations – converting, cropping, resizing, rotating, flipping… Plus it let’s you do some really cool affects. All is done super easily. Combining operations can produce some very cool results. Download Download EasyImage.jar Download source View in GitHub JavaDoc Click here to see full java doc. Operations Open image. Save image Convert image Re-size image Crop image Convert to black and white image Rotate image Flip image Add color to image Create image with multiple instance of the original Combining 2 images together Emphasize parts of the image Affine transform image Examples Combining 2 pictures Emphasizing parts of the image Affine transform + combine Add color to image Add to pixel color Image resizing + multiplying with pixel color enhancement Combine image with image without background Emphasize trick
From time to time I like to make small projects that are good for nothing. This weekend I have created a small project that I call “HTML image maker”. Description It’s purpose is to take existing images and to generate HTML table where each pixel is replaced by a table cell. It is also possible to insert text inside the cells where the color of the cell is at the background of the text or in the foreground. If you won’t insert input image than the program will simply create a screen shot image instead. Used technologies The image manipulation is done using java’s ImageIO object. The user interface was built using Apache Pivot. Screen shots Click to enlarge. Download the software Download the sources (eclipse project) View on github Instructions No need to install. To start the program execute Html image maker.bat. Optional – Insert input image path. If you won’t insert input image than the image will be generated from the screen shot. Insert an output path for the Html file. Optional – You can enter text to be inserted inside the image. Select foreground if you would like to color the text itself instead of the background. Continue reading HTML image maker
I just got to know to Pivot and I have to say, I love it. Pivot is a technology to create Java applets for RIA or desktop applications with the use of XML and/or code. When I write applications at home I don’t want waste time writing swing or applets myself. Pivot helps me designing the GUI with use of XML. It is that simple and the cool thing is that you can run it as a web page and a desktop application. An example of a Pivot XML (WTKX): After creating the XML, you can refer to the GUI components from the code. Actually the entire GUI can be built just from the code, but I like the XML way better. The application can be run from the IDE or can be referred from a web page as an applet. All you have to do is refer to the Pivot jars + your jar and give the full name of your application class you have created. The result: The Pivot web site contains loads of examples with the use of their components. download sample project for Eclipse but don’t forget also to download Pivot jars. See also Pivot website Continue reading Apache Pivot. Making Java GUI is easy.