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Obba 3.1: A Java Object Handler for Spreadsheets (for Dynamic Client/Server Spreadsheet Add-Ins)

06.10.2012
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New in version 3.1: Support for creating objects dynamically from source code, see Class to Object Demo (movie).

Obba iconObba provides a bridge between spreadsheets and Java classes. With Obba, you can use spreadsheets as GUIs (Graphical User Interfaces) for your Java libraries. Compatible with Excel/Windows, OpenOffice/Win/Mac/Linux, LibreOffice/Win/Mac/Linux, NeoOffice/Mac.

Obba's main features are: Obba Diagram

  • Stateful access to almost all objects and methods running in a Java virtual machine via a fixed set of spread sheet functions.
  • Client/server support: The Java virtual machine providing the add-in may run on the same computer or a remote computer - without any change to the spreadsheet.
  • Loading of arbitrary jar or class files at runtime through a spreadsheet function.
  • Instantiation of Java objects, storing the object reference under a given object label.
  • Invocation of methods on objects referenced by their object handle, storing the handle to the result under a given object label.
  • Asynchronous method invocation and tools for synchronization, turning your spreadsheet into a multi-threaded calculation tool.
  • Allows arbitrary number of arguments for constructors or methods (avoids the limitation of the number of arguments for Excel worksheet functions).
  • Serialization and de-serialization (save Serializable objects to a file, restore them any time later).
  • All this through spreadsheet functions, without any additional line of code (no VBA needed, no additional Java code needed).

 

Use cases:

  • For Spreadsheet Users: Creating powerful spreadsheet calculations using external libraries, running calculations in Java.
  • For Java Developers: Testing, debugging and analyzing Java libraries with spreadsheets. Setting up unit test in spreadsheets. Using spreadsheets as GUI to your object while debugging.

Advanced Features:

  • Run Obba server (and its JVM) on one machine, while the spreadsheet (with Obba add-in) runs on another machine.
  • Obba allows to create an object from Java source code (dynamically compile source to java.lang.Class, re-load the class definition and instantiate an object from it), see Class to Object Demo (movie).

For tutorials see Obba tutorials. For a more detailed introduction see Obba documentation.

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