EXAMPLE-A

You could consider to build your application on top of the NetBeans Platform (a Swing based RCP) and reuse parts of the NetBeans GUI Builder or the Visual Library:

http://platform.netbeans.org/graph/

Or you could have a look at my customizer framework I wrote some years ago for such tasks: Move and resize components with the mouse and allow further customizations. "Snap-to-grid"-feature included! Maybe you find it useful. (It's open source!)

I started to write a tutorial (still under construction!):

http://softsmithy.sourceforge.net/lib/docs/tutorial/swing/customizer/index.html

For adding components see:

http://softsmithy.sourceforge.net/lib/docs/api/org/softsmithy/lib/swing/CustomizerBar.html

To customize properties use:

http://softsmithy.sourceforge.net/lib/docs/api/org/softsmithy/lib/swing/JCustomizerPropertyTable.html

Register it to the SelectionManager of the JCustomizerPane and set the CustomizableProperties-property of the JCustomizer objects.

Also have a look at the subclasses of JCustomizer.

E.g. there are

customizers for images & shapes:

http://softsmithy.sourceforge.net/lib/docs/api/org/softsmithy/lib/swing/JXIconCustomizer.html

a label customizer with inline editing:

http://softsmithy.sourceforge.net/lib/docs/api/org/softsmithy/lib/swing/JLabelCustomizer.html

a line customizer:

http://softsmithy.sourceforge.net/lib/docs/api/org/softsmithy/lib/swing/JLine2DCustomizer.html

And there are many classes providing support for menu- and toolbar-actions. (Incuding support for some of the "Java Look and Feel Graphics Repository" actions.)

Look at the *.swing and the *.swing.action packages.

Just ask me if you don't find them.

Homepage:

http://www.softsmithy.org

Download:

http://sourceforge.net/projects/softsmithy/files/softsmithy/

Maven:

<dependency>  
    <groupid>org.softsmithy.lib</groupid>  
    <artifactid>softsmithy-lib-core</artifactid>  
    <version>0.2</version>  
</dependency>

API:

http://softsmithy.sourceforge.net/lib/docs/api/index.html

Gui Builder Api