Compiere Scripting Help
Variables
The available variables are loaded from the environment. The variables starting 
  with '_' are global variables. The color codes are:
  - boolean (orange)
- double (cyan)
-  int (blue)
- Timestamp (magenta)
- String (green)
- Object (red)
Please 
check the updated online version on http://www.compiere.org/technology/integration/scripting.html