jWidgets to make it easier to develop Eclipse based components for composite applications

Perusing the the Composite Application Wiki I discovered a technology IBM calls jWidgets. Basically they are for Composite Application Java component development what iWidgets are to websites that is a widget framework for easily and more quickly doing stuff. Developing Java components for composite applications is a little hard as you have to manage wires etc. yourself. A framework would make that a lot easier and that’s exactly what jWidgets are.

Having the technology available to Lotus Notes (and not just Lotus Expeditor) would be really cool. From an IBM’er I however learned that they haven’t been formally tested in Notes, but the technical capability is there. They have only been tested formally in Lotus Expeditor 6.2.2.

jWidgets – Easy Creation of Java Composite Application Components

Why all the talk about recycle() – how about dispose()?

Let me start by saying that I agree that recycle() could and should be handled by the API and there are numerous ways around it. I however also think that the majority of Notes developers out there will never have the need to call recycle() in their Java agents. There is a lot of talk about recycle() this and recycle() that but let’s face it – it’s not really a problem. If ever there is a problem with the Java API it’s not recycle() it is the fact that it has been left to stagnate and that it’s not keeping up with the Java language as a whole.

All this being said I wonder why so much talk and energy is being spent on recycle() and how come it is constantly being used as a reason not to move to Java and embrace the language. Looking at other API’s there are stuff that needs to be done. In the Java API it’s recycle() (whenever it’s actually needed) and in SWT it’s dispose(). I never see any SWT discussions on the dispose() method and DisposeListeners and using it as a justification for not choosing SWT and Eclipse as the fundation for an application. You judge a framework on what it does for you and not a single method in an API. Every API and language has quirks. Deal with it!

My post from 2006 (!!) has a lot more information on recycle() and why it’s there: Java in Notes/Domino Explained: The story on recycle()

The Next Release of Java: Java JDK 7, out mid-2011

News from JavaOne:


Mark Reinhold confirmed that “Plan B” is now the plan of record for the next release of Java, with JDK 7 scheduled for mid-2011, with support for other languages on the JVM (InvokeDynamic) and many small improvements (parts of Project Coin). Things that don’t make it into JDK 7 are planned for JDK 8, including Project Lambda and Project Jigsaw, scheduled for late 2012. Markus Eisele, software architect, provides details about Java SE 7 and Java SE 8.

Janice J. Heiss: Plan B Wins

So there’s no stuff out there on plug-in development?

Well I just did a quick search on developerWorks and it gave me a lot of info. Among others were the below articles that I think look very interesting. Especially those two first ones look like something that would be of interest to a lot of people venturing into this area.

Eclipse Fall Training Series

“The Eclipse Foundation and Eclipse member companies are pleased to announce the fall 2010 training class series. The training is an excellent opportunity for software developers and architects to learn more about Eclipse Rich Client Platform (RCP), BIRT and Modeling technologies. Eclipse experts will lead the sessions, providing practical experience through classroom instruction and hands-on labs. Virtual and on-site classes have been scheduled in several countries from September 20 to November 5, 2010. “

Eclipse Fall Training Series

Updated! Introduction to Java programming

A lot of people ask me how to get started with Java programming so when I saw the below entry in the developerWorks newsletter I thought it should be communicated as far and wide as possible.

“developerWorks Java contributor Steve Perry took on the Herculean task of updating the “Introduction to Java programming” tutorials. This two-part series introduces the structure, syntax, and programming paradigm of the Java language and platform.”

Get started with Java technology

How to extend Notes 8: dynamic LiveText recognizers using Java

As I briefly described in my last post (“How to extend Notes 8: dynamic extensions using Java“) it’s possible to create new extensions to Lotus Notes using Java and hence inject functionality into the client dynamically. It’s very cool functionality and it allows you to inject anything from content types and recognizers to sidebar panels.

In this post I’ll build on three previous posts and show you how to use dynamic extensions in Lotus Notes in combination with a Java action that uses multiple capture groups for an end-to-end solution that may be deployed as a single Java extension (aka plugin). The result is a plugin that may be deployed to a client workstations which allows you to act on text recognized by the LiveText sub-system but where you have the power of Java for processing.

All the posts in the series may be found under the extending_notes8 tag.

We need three pieces of information:

  1. The code to dynamically inject our custom recognizer and content type into Lotus Notes without the need for an extension.xml file. This is what the LiveText sub-system uses to highlight the text for us.
  2. The Java action to act on the LiveText selection.
  3. The plugin.xml file to bind it all together.

The first piece is the code that injects the custom recognizer and content type under a known id. This code may be run in lots of ways but to make it easy for this example I choose a sidebar panel. Below is the createPartControl-method from that class.

public void createPartControl(final Composite parent) {
  try {
    // define XML
    final String extensionXml = ...;

    // get extension registry and load extension
    // into registry
    final IExtensionRegistry reg = Platform.getExtensionRegistry();
    InputStream ins = new ByteArrayInputStream(extensionXml.getBytes());
    Bundle bundle = Activator.getDefault().getBundle();
    IContributor contr = ContributorFactoryOSGi.createContributor(bundle);
    reg.addContribution(ins, contr, false, null, null, null);

  } catch (Throwable t) {
    t.printStackTrace();
  }
}

The above code injects the recognizer and content type with an id of DCCT.ExampleContentType.1234567890 into the client.

The next part we need is the action class (again implementing org.eclipse.ui.IObjectActionDelegate) to act on the LiveText selection. Most of the code you’ve seen before in a previous post but again it goes and get the text from the underlying document as document properties.

public void selectionChanged(IAction action, ISelection selection) {
   IDocumentContent doc = null;

   // cast/adapt selection
   if (selection instanceof StructuredSelection) {
      Object sel = ((StructuredSelection)selection).getFirstElement();
      if (sel instanceof IDocumentContent) {
         doc = (IDocumentContent)sel;
      }
   } else if (selection instanceof IDocumentContent) {
      doc = (IDocumentContent)selection;
   } else {
      // try and adapt
      IAdapterManager amgr = Platform.getAdapterManager();
      doc = (IDocumentContent)amgr.getAdapter(selection,
          IDocumentContent.class);
   }
   if (null == doc) {
      this.contents = null;
      this.prodFamily = null;
      this.partNumber = null;
      return;
   }

   // get data from document property
   this.contents = doc.getProperties().getProperty("contents");
   this.prodFamily = doc.getProperties().getProperty("pf");
   this.partNumber = doc.getProperties().getProperty("pn");
}

The last piece is the plugin.xml to put it all together using the org.eclipse.ui.popupMenus extension point. Notice how we use the content type id we know (bold text below) from our dynamically deployed content type.

<extension
  point="org.eclipse.ui.popupMenus">
  <objectContribution
    id="com.lekkimworld.extnotes8.dynext.objCtr1"
    objectClass="com.ibm.rcp.content.IDocumentContent">
    <visibility>
      <and>
        <objectState
          name="content.type"
          value="DCCT.ExampleContentType.1234567890">
        </objectState>
        <objectState
          name="contents"
          value="*">
        </objectState>
      </and>
    </visibility>
    <action
      class="com.lekkimworld.extnotes8.dynext.MyAction"
      enablesFor="*"
      id="com.lekkimworld.extnotes8.dynext.action1"
      label="Do me!">
    </action>
  </objectContribution>
</extension>

The result when deployed to a Lotus Notes client is something like the screenshot below where you get a Java action to act on a LiveText recognition. Only change this time is that all the functionality is provided from your plugin. No separate extension.xml is necessary for the recognizer or the content type.

That’s how it’s done. I’ve uploaded an Eclipse project to the blog so you can download it and install it in your Eclipse as a demo. You can download the project here.

How to extend Notes 8: dynamic extensions using Java

I get so many question on how to extend Notes 8 that I finally decided to create a series of blog posts on how to do it. All the posts in the series may be found under the extending_notes8 tag. In all of the examples I assume a working knowledge of Eclipse and Java programming and how to work with extension points.

As I briefly mentioned in my last post (“How to extend Notes 8: capture group LiveText recognizers with a Java action“) it’s possible to create new extensions to Lotus Notes using Java and hence inject functionality into the client dynamically. It’s very cool functionality and it allows you to inject anything from content types and recognizers to sidebar panels. I’ve used this a lot previously and also demoed it in my “How dynamic are your Notes sidebar plugins?” demo. Watch the Flash video and see how you can make sidebar panels come and go on demand.

Now on to the code…

The trick to dynamic extensions is to inject extensions into the Extension Registry at runtime. The Extension Registry is where Eclipse reads the plugin contributions from plugin.xml files into at startup. If we inject an extension, and the receiving plugins are set up to handle dynamically adding extensions you are golden. Let me show you have to use the Extension Registry.

final String extensionXml = ...;
final IExtensionRegistry reg = Platform.getExtensionRegistry();
InputStream ins = new ByteArrayInputStream(extensionXml.getBytes());
Bundle bundle = Activator.getDefault().getBundle();
IContributor contr = ContributorFactoryOSGi.createContributor(bundle);
reg.addContribution(ins, contr, false, null, null, null);

The code does the following:

  1. Defines the extension XML to add (more on this later).
  2. Gets the extension registry from the platform.
  3. Reads the extension XML into an input stream.
  4. Retrieves the bundle.
  5. Creates a new contributor that is the object that makes the contribution to the extension registry.
  6. Adds the contribution to the registry.

So what is the extension XML mentioned above?

The extension XML is the XML that defines the extension you’re adding. It’s actually any piece of XML you would stick in your plugin.xml file either manually or using the UI editor. An example could be a custom recognizer and content type as shown below as a snippet from Java.

final String extensionXml = "<?xml version="1.0" encoding="utf-8" ?>" +
"<?eclipse version="3.2"?>" +
"<plugin>" +
"<extension id="DCR.ExampleRecognizer.%s"
   point="com.ibm.rcp.annotation.regex.regexTypes">" +
"<regexTypes contentTypeId="DCCT.ExampleContentType.%s"
   id="DCR.ExampleRecognizer.%s" match="([A-Z]{4})-(\d{4})"
   name="Example Recognizer">" +
"<group contentTypePropertyId="pn" number="2"/>" +
"<group contentTypePropertyId="pf" number="1"/>" +
"<group contentTypePropertyId="contents" number="0"/>" +
"</regexTypes>" +
"</extension>" +
"<extension id="DCCT.ExampleContentType.%s"
   point="com.ibm.rcp.content.contentTypes">" +
"<contentSet>" +
"<type category="Recognized Content"
   id="DCCT.ExampleContentType.%s"
   name="Example Content Type">" +
"<property description="Entire Contents" id="contents"/>" +
"<property description="Product Family" id="pf"/>" +
"<property description="Part Number" id="pn"/>" +
"</type>" +
"</contentSet>" +
"</extension>" +
"</plugin>";

That’s how you do it. Tomorrow I’ll show how to combine it with our custom recognizer and content type to inject it dynamically into the LiveText system in Lotus Notes. Stay tuned…

How to extend Notes 8: capture group LiveText recognizers with a Java action

I get so many question on how to extend Notes 8 that I finally decided to create a series of blog posts on how to do it. All the posts in the series may be found under the extending_notes8 tag. In all of the examples I assume a working knowledge of Eclipse and Java programming and how to work with extension points.

For this post I’ll build on the “How to extend Notes 8: coupling LiveText to a Java action” and “How to extend Notes 8: using LiveText with capture groups” posts and show how to act on your own custom recognizer from a Java action when you have multiple capture groups.

Please note: I’ll assume that you read the “How to extend Notes 8: using LiveText with capture groups” post and have it working as we’ll build on that example in this post. Unfortunately as we act on the content type id you need to find the id of the content type on your system. I’ll show you how.

Enough with preparations – now on to the code!

So far we have our custom recognizer and our custom content type but instead of a web widget we really want to use our Java action as the recipient of the LiveText selection. We couple the Java action to the content type using an extension point in plugin.xml based on the content type id. Let me show you how to find the content type id.

  1. Start by opening the management UI for widgets, content types and recognizers. You do this by choosing “Manage Widgets, Content and Recognizers” from the part menu in the My Widgets sidebar panel as show below.
  2. Now switch to the “Content Types” panel and make a note of the ID for the “Demo Product Number” content type. Here the id is “DemoProductNumber.1410710777” as highlighted below.
  3. Now comes the trick. Notes adds “DCCT.” in front of the id shown so the real id is “DCCT.DemoProductNumber.1410710777”. Make a note of your own id and read on…

As previously the first piece of the puzzle is the extension point. Add an org.eclipse.ui.popupMenus extension as previous and specify the id you noted above as the content type id. Mine is shown below – notice how I use the id prefixed with “DCCT.”.

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.4"?>
<plugin>
   <extension  point="org.eclipse.ui.popupMenus">
      <objectContribution id="com.lekkimworld.livetxt.objectContr1"
         objectClass="com.ibm.rcp.content.IDocumentContent">
         <visibility>
            <and>
               <objectState name="content.type"
               value="DCCT.DemoProductNumber.1410710777"/>
               <objectState name="contents" value="" />
            </and>
         </visibility>
         <action class="com.lekkimworld.livetext.MyAction"
            enablesFor="*"
            id="com.lekkimworld.livetxt.action1"
            label="Do stuff!" />
      </objectContribution>
   </extension>
</plugin>

Now create your Java action class – again implemening org.eclipse.ui.IObjectActionDelegate – and specify the correct class name in the extension point.

Again when it comes to grabbing the contents of the recognized LiveText it comes down to you selectionChanged-method of your Java action. As our recognizer uses capture groups we have a few choices for the properties we can grasp from the document. As always the entire recognized product number will be in the “contents” property but we also have “pf” and a “pn” property available that holds the product family and the part number. The example code below shows how to get at these.

public void selectionChanged(IAction action, ISelection selection) {
   IDocumentContent doc = null;

   // cast/adapt selection
   if (selection instanceof StructuredSelection) {
      Object sel = ((StructuredSelection)selection).getFirstElement();
      if (sel instanceof IDocumentContent) {
         doc = (IDocumentContent)sel;
      }
   } else if (selection instanceof IDocumentContent) {
      doc = (IDocumentContent)selection;
   } else {
      // try and adapt
      IAdapterManager amgr = Platform.getAdapterManager();
      doc = (IDocumentContent)amgr.getAdapter(selection,
          IDocumentContent.class);
   }
   if (null == doc) {
      this.selection = null;
      return;
   }

   // get all recognized content
   this.prodNumber = doc.getProperties().getProperty("contents");
   this.prodFamily = doc.getProperties().getProperty("pf");
   this.partNumber = doc.getProperties().getProperty("pn");
}

Now when you install the extension and hence put the pieces together you should see two actions for the product number LiveText recognition as shown below. The top one is our Java action and the bottom one is our web widget from previously.

That’s what is required to act on custom recognizers. As you can probably gather from the above it doesn’t work letting users do their own recognizers and then wanting to act on them from Java due to two reasons – 1) never trust a user to give it the right name as instructed 🙂 and 2) the id of the content type will change from machine as it is generated when the user creates the content type. It is possible however if you create the content type and the recognizer for users and install then using an extension.xml file as the extension.xml sets the id’s. That’s probably also the way you’d want it.

There is however an even better solution… Dynamically add the content type and recognizer to the client from Java for a single, combined solution. Stay tuned…