Select the Java Preferences... command to open the preference pages containing options relating to the Variables View and the Expressions View.
There are four pages in total that are shown, all as entries in the tree on the left hand side of the Preferences Dialog.
These pages are:
Java > Debug > Detail Formatters preference page.
Java > Debug > Heap Walking preference page.
Java > Debug > Logical Structures preference page.
Java > Debug > Primitive Display Options preference page. This command applies to: