What is the eclipse shortcut for auto-generating a default and field constructor?

Type the first letter of your class, then press Ctrl+Space, Eclipse will list suggestions within a combobox. The topmost suggestion is the default constructor. Press Enter, it will be done. (I'm using Eclipse Juno and it works.)

Goto Source ---> Generate constructor using Fields

Under Source Title bar, select the Generate constructor using Fields option.

Or

Ctrl+Space which displays the various suggestions possible, from there you can go for the default contructor.

Ways to Generate default Constructor -
1) Press Ctl + Space

Ways to Generate field Constructor -
1) Press Alt + Shift + S + O
2) Right click -> Source -> Generate Constructor using field
3) Go to Source menu -> Generate Constructor using field
4) Go to Windows menu -> Preferences -> General -> Keys (Write Generate Constructor using field on text field)

Alt+Shift+s and then o opens the Generate Constructor using Fields dialog.