The JDeveloper Code Insight has been greatly improved and
handles more cases than ever before including JSP Tag Insight, etc.
I think your problem maybe that it is either it is disabled
or the keyboard accelerator set you have chosen has a different mapping.
.
To Enable Code Insight,
Select menu Tools | Preferences
Navigate to the "Editor"."Code Insight" Tab
Check the two [X] Enable ... fields
Press "OK"
.
If this does not do it, then it is caused by your having
a different keyboard accelerator set selected.
.
To Set the Default Keyboard accelerators,
Select menu Tools | Preferences
Navigate to the "Accelerators" Tab
Press the "Load Presets..." button
Select the "Default" preset and press OK
Note: this is the key for Category:Code Editor / Action:Completion insight / Accelerator:Ctrl+Space
Press OK
Happy Programming