# Java Preferences

The following Java preferences can be set on the Java preference page and its sub-pages.

- Appearance
- Build Path
- Code Style
- Compiler
- Debug
- Editor
- Installed JREs
- JUnit
- Properties File Editor

Option | Description | Default
--- | --- | ---

Action on double click in the Package Explorer

Go into the selected element
  When you double click a container, a Go Into command is executed.
  See Go Into from the Navigate menu.
Expand the selected element
  When you double click a container, it is expanded and its children are revealed.

Expand the selected element

When opening a Type Hierarchy

Open a new Type Hierarchy Perspective
  Opens a new Type Hierarchy perspective whenever a Type Hierarchy view is opened.
Show the Type Hierarchy View in the current perspective
  The Type Hierarchy view is displayed in the current perspective.

Note: On the Workbench preferences page, you can choose whether new perspectives open in a new window, in the current window, or as a replacement for the current perspective.

Show the Type Hierarchy View in the current perspective

Refactoring Java code

Save all modified resources automatically prior to refactoring
  If this option is turned off, refactorings may prompt to save modified files if required. If it is turned on, all modified files are saved without prompting prior to opening a refactoring wizard.

Off

Rename in editor without dialog
  If this option is turned on, then the rename refactoring will not show a dialog if invoked inside a Java editor. Instead the new name for the element to rename can be typed into the editor right away.

On

Search

Use reduced search menu
  If this option is turned on, the search context menus show only the most frequently used search actions.

On

Search

Enable new Java index
  If this option is turned on, Eclipse will build and use a new index for accelerating many Java operations. This will reduce the number of UI freezes but will consume additional memory and disk space.

Off

Search

Rebuild Index
  Pressing this button will delete all information cached in the Java index. This can be used to save disk space since the rebuilt index is often smaller than the original. It can also be used to fix index corruption in cases where types appear to be missing from the UI.

Java dialogs

Clear all 'do not show again' settings and show all hidden dialogs again
  If pressed, all 'do not show' settings are cleared.

Button

### Related Concepts

Java views

### Related References

Package Explorer view
Type Hierarchy view