Developer Papercuts

At the Eclipse Summit Europe I listened to a talk of Boris Bokowski about Eclipse and the Web.

Among other things I learned that you can execute JavaScript directly on the SWT Browser Widget and I wanted to give a tiny example for this.

This Eclipse view will for example load my webpage and then execute a tiny JavaScript (alert(“1″);) in the browser.

package de.vogella.swtbrowser;

import org.eclipse.swt.SWT;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.browser.ProgressEvent;
import org.eclipse.swt.browser.ProgressListener;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.part.ViewPart;

public class View extends ViewPart {

	public static final String ID = "de.vogella.swtbrowser.view";

	public void createPartControl(Composite parent) {
		final Browser b = new Browser(parent, SWT.NONE);
		b.setUrl("www.vogella.de");
		b.addProgressListener(new ProgressListener() {
			@Override
			public void completed(ProgressEvent event) {
				System.out.println("Page loaded");
				System.out.println(b.execute("alert(\"1\");"));
			}
			@Override
			public void changed(ProgressEvent event) {
			}
		});
	}

	/**
	 * Passing the focus request to the viewer's control.
	 */
	public void setFocus() {
	}
}

Thanks to Boris for the great talk.

At the Eclipse Summit Europe I listened to a talk of Boris Bokowski about Eclipse and the Web. Among other things I learned that you can execute JavaScript directly on the SWT Browser Widget and I wanted to give a tiny example for this. This Eclipse view will for example load my webpage and then ...

The Eclipse platform provides an API to allows that you can access in information of the MANIFEST.MF. For example you could read the dependencies of your plugin.

For this example create a plugin “de.vogella.pde.dependencies”. See Eclipse Plugin development for examples on how to develop plugins. Use the “Hello, World Command” template.

Define dependendies to the following plugins:
– org.eclipse.ui
– org.eclipse.core.runtime

Change the command to the following.

package de.vogella.pde.dependencies.handlers;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.Platform;
import org.eclipse.osgi.util.ManifestElement;
import org.osgi.framework.BundleException;
import org.osgi.framework.Constants;

public class PrintDependencies extends AbstractHandler {
	public Object execute(ExecutionEvent event) throws ExecutionException {
		String requireBundle = (String)Platform.getBundle("de.vogella.pde.dependencies").getHeaders().get(
				Constants.REQUIRE_BUNDLE);
				try {
					ManifestElement[] elements = ManifestElement.parseHeader(
					Constants.BUNDLE_CLASSPATH, requireBundle);
					for (ManifestElement manifestElement : elements) {
						System.out.println( manifestElement.getValue());
					}
				} catch (BundleException e) {
					e.printStackTrace();
				}
		return null;
	}
}

If you now run your new plugin it and select your command it will print out the dependencies of your plugin.

The Eclipse platform provides an API to allows that you can access in information of the MANIFEST.MF. For example you could read the dependencies of your plugin. For this example create a plugin "de.vogella.pde.dependencies". See Eclipse Plugin development for examples on how to develop plugins. Use the "Hello, World Command" template. Define dependendies to the ...

I have to use Microsoft Windows on my laptop due to several required applications which only run on Windows. Due to this fact I lost a little bit sight of KDE over the last years.

While reading a blog post about the latest KDE 4 isn’t too bad after all I remembered that the KDE project started a port of the major KDE applications to Windows a few years ago.

It seems that this project is very active and is producing impressive results.

KDE on Windows

They even have an installer for Windows.

Windows Installer for KDE

Unfortunately when I tried to use KNode I received a memory error. For details please see the KNode Bug report .

But I assume that solving this issue will only be a matter of time and that soon I’ll be able to use the powerful KDE Personal Information Manager (PIM), e.g. Kmail, Kalendar, KNode, on Windows.

Many thanks to the KDE team!

I have to use Microsoft Windows on my laptop due to several required applications which only run on Windows. Due to this fact I lost a little bit sight of KDE over the last years. While reading a blog post about the latest KDE 4 isn't too bad after all I remembered that ...

In this episode of Eclipse Papercuts I will demonstrate how to modify the Mylyn tasks context. Many thanks to David Green for providing sample code to access the Mylyn context.

Mylyn makes certain assumptions how the developer works. If you start a new task the Mylyn context is empty and fills up based on the selected files.

Which is not always the way I work. Frequently I know that for my task a whole package (or project) is relevant. I would like to include all classes in this package / project in my Mylyn task.

Ok, lets see how we can solve this papercut. I describe how to add Java classes from a package to an active task.

Create an command which extends the package explorer with a new popup commands as described here Extend the package explorer.

Create the command handler with the following coding:

package de.vogella.mylyn.tasksmodify.handlers;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IPackageFragment;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.mylyn.context.core.ContextCore;
import org.eclipse.mylyn.context.core.IInteractionContext;
import org.eclipse.mylyn.internal.context.core.ContextCorePlugin;
import org.eclipse.mylyn.monitor.core.InteractionEvent;
import org.eclipse.mylyn.monitor.core.InteractionEvent.Kind;
import org.eclipse.ui.handlers.HandlerUtil;

public class SampleHandler extends AbstractHandler {
	public Object execute(ExecutionEvent event) throws ExecutionException {

		IStructuredSelection selection = (IStructuredSelection) HandlerUtil
				.getActiveMenuSelection(event);
		if (selection ==null){
			return null;
		}

		Object firstElement = selection.getFirstElement();

		if (firstElement instanceof IPackageFragment) {
			IPackageFragment mypackage = (IPackageFragment) firstElement;
			try {
				if (mypackage.getKind() == IPackageFragmentRoot.K_SOURCE){
					 ICompilationUnit[] compilationUnits = mypackage.getCompilationUnits();
					 for (ICompilationUnit iCompilationUnit : compilationUnits) {
						 IInteractionContext activeContext = ContextCore.getContextManager()
							.getActiveContext();
						 ContextCorePlugin.getContextManager().processInteractionEvent(iCompilationUnit,
									Kind.PROPAGATION, InteractionEvent.ID_UNKNOWN, activeContext);
					}
				}
			} catch (JavaModelException e) {
				e.printStackTrace();
			}
		}

		return null;
	}
}

Launch your plugin. Create a Mylyn task and select a package in the package explorer. Select your commands and all files of this package will be added to the task.

Further reading: If you want to access other Java Elements, e.g. Project and add them to the Mylyn task this tutorial might help you: Eclipse JDT.

Please note that ContextCorePlugin is supposed to be internal API but I did not find another way of accessing the Mylyn tasks.

Change the Mylyn context in a task