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TASK:
Change a diagram editor generated by GMF to make its figures sensitive to changes of semantic elements’ attributes’ values. Changes of attributes’ values should be automatically detected and reflected in figures’ look.

SOLUTION:
You have to make a little change in *EditPart class. I’m going to change edit part for the semantic model element named Port, so I will edit my.package.diagram.edit.parts.PortEditPart class.

Add a new method to the PortFigure class, which is PortEditPart’s inner class:

	public void updateFace() {
		Port port = (Port) ((Node) PortEditPart.this.getModel()).getElement();
 
		// set line width according to number of some children
		int lineWidth = 1;
		if (port.getLogicalUnits().size() > 1) {
			lineWidth = 2;
		}
		this.setLineWidth(lineWidth);
 
		// update tooltip
		String tooltipText;
		if (port.getDescription() != null
				&& port.getDescription().length() > 0) {
			tooltipText = port.getDescription();
		} else {
			tooltipText = port.getName();
		}
		if (getToolTip() == null) {
			setToolTip(new Label(tooltipText));
		} else if (getToolTip() instanceof Label) {
			((Label) getToolTip()).setText(tooltipText);
		}
	}

The updateFace method makes actual changes to the figure’s look. This example implementation sets the line’s width according to the number of Port’s children (port.getLogicalUnits().size()) and sets the tool-tip text to the value of element’s attribute named description.

Then you have to hook up this method in two places: PortFigure’s constructor to update the look when editor starts and the handleNotificationEvent method to react to live changes.

Change PortFigure’s constructor to make it use new method.

	/**
	 * @generated NOT
	 */
	public PortFigure() {
		this.setFill(true);
		this.setFillXOR(false);
		this.setOutline(true);
		this.setOutlineXOR(false);
		this.setLineStyle(Graphics.LINE_SOLID);
		//this.setLineWidth(1);
		//this.setForegroundColor(PORTFIGURE_FORE);
		//this.setBackgroundColor(PORTFIGURE_BACK);
		updateFace();
		createContents();
	}

Override handleNotificationEvent(Notification notification) method in PortEditPart.

	@Override
	protected void handleNotificationEvent(Notification notification) {
		if (notification.getNotifier() instanceof Port) {
			getPrimaryShape().updateFace();
		}
		super.handleNotificationEvent(notification);
	}

Without this method you would need to restart editor to reflect element’s changes in figure parameters.

Tested on GMF version 2.0.

Sometimes it is useful to have image size written in filename (I needed it when I was browsing my collection of wallpapers). I could not find any tool which would automate this process, so I have decided to write one. Probably it is job for bash or Python but I like Java most, so it is Java CLI tool. I have used ImageInfo class to get image parameters.

That’s what it does:

• scans all parameters for options – there is only one valid option: -p which switches the tool from the dry mode (tool only shows what should be done) to the working mode
• for every non-option parameter:
  • check if it is path to an image
  • read image width and height from the file
  • check if the file name already contains valid info about the image size
  • if need be, remove invalid info from the file name
  • put WIDTHxHEIGHT string at the beginning of the file name

Use it like this:

# to preview changes:
$  java -jar /some-path/into-filename.jar file1 file2 ... # you can use full file paths
# to rename files:
$  java -jar /some-path/into-filename.jar -p file1 file2 ...

And here is the jar: into-filename (Public Domain License)

This solution is for those who use also GMF. In one of your plug-ins (or create a new empty plug-in for that) add following section to plugin.xml:

<extension point="org.eclipse.emf.ecore.extension_parser">
   <parser type="MY_SEMANTIC_MODEL_FILE_EXTENSION"
      class="org.eclipse.gmf.runtime.emf.core.resources.GMFResourceFactory">
   </parser>
</extension>

It will make EMF use GMFResourceFactory for XMI [de]serialization. GMFResourceFactory enables usage of UUIDs. Don’t forget to replace MY_SEMANTIC_MODEL_FILE_EXTENSION with your own file extension.

Currently I’m writing NetFlow analyser as a Rich Internet Application. After long consideration and evaluation of available open-source technologies I have concluded that GWT will be the best shot in this case (now I’m not so sure any more, but this is another story). To make building nice user interface easier I have decided to equip user side CLASSPATH with GWT-Ext library. GWT-Ext reuses ExtJS and ExtJS needs some underlying JavaScript framework. A lot of people use YUI as base for ExtJS, so automatically I have started to use it too. And this is where the first problems arose.
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