Shortcut keys make life that little bit quicker! They aid you in working faster and become very handy when programming in Eclipse.
For a full list of shortcuts, in Eclipse 3.1 and above you can press Ctrl+Shift+L for a handy popup.
Shortcuts:
Ctrl+Shift+T
Find Java Type
Start typing the name and the list gets smaller. Try typing the capital letters of the class only (e.g. type "CME" to find "ConcurrentModificationException")
Ctrl+Shift+R
Find Resource
Use this to look for XML files, text files, or files of any other type. which are in your workspace.
Ctrl+E
Open Editor Drop-Down
Presents a popup window listing currently opened files. Start typing to limit the list or simply use the down arrow key.
Ctrl+O
Quick Outline
Use this to find a method or a member variable in a class. Start typing to limit the choices. Press Ctrl+O a second time to include inherited methods.
Ctrl+Space
Content Assist
Context sensitive content completion suggestions while editing Java code.
Ctrl+Shift+Space
Context Information
If typing a method call with several parameters use this to show the applicable parameter types. The current parameter where the cursor is will be shown in bold.
Ctrl+Shift+O
Organize Imports
After typing a class name use this shortcut to insert an import statement. This works if multiple class names haven't been imported too.
F3
Open Declaration
Drills down to the declaration of the type, method, or variable the cursor is on. This works much like a browser hyperlink.
Alt+Left
Backward History
This works like a browser's Back button.
Alt+Right
Forward History
This works like a browser's Forward button
Ctrl+L
Go to Line
Go to a specific line number.
F4
Open Type Hierarchy
Show the type hierarchy (downward tree) or the supertype hierarchy (upward tree).
Ctrl+Alt+H
Open Call Hierarchy
Show where a method is called from. In the Call Hierarchy view keep expanding the tree to continue tracing the call chain.
Ctrl+H
Open Search Dialog
Opens a search dialog with extensive search options for Java packages, types, methods, and fields.
Alt+Shift+R
Rename - Refactoring
Use this to rename type, method, or field. All existing references will be refactored as well.
Alt+Shift+L
Extract Local Variable
Use this to create a local variable from the selected expression. This is useful for breaking up larger expressions to avoid long lines.
Alt+Shift+M
Extract Method
Use this to extract a new method from existing code. The parameter list and return type will be automatically created.
Alt+Shift+Up
Alt+Shift+Down
Alt+Shift+Left
Alt+Shift+Right
Select Enclosing Element / Restore Last Selection / Select Previous Element /
Select Next Element
Useful for selecting context-sensitive blocks (e.g. surrounding loop, method, class, etc.)
Ctrl+Up
Ctrl+Down
Scroll Line Up / Scroll Line Down
Very handy if you want to scroll by 1 line without changing your cursor position or using the mouse.
Ctrl+Shift+U
Alt+Shift+U
Go to Previous Member / Go to Next Member
Great for stepping down through the methods of a Java source file.
Ctrl+Shift+U
Alt+Shift+U
Show Occurrences in File / Remove Occurrences Annotations
Use this to search within the same file - useful for occurrences of private fields and methods.
Ctrl+Shift+P
Go to Matching Bracket
Helps to find the closing bracket of lengthly if-else statements.
Ctrl+J
Ctrl+Shift+J
Incremental Find / Reverse Incremental Find
The first matching occurrence is shown with each typed letter. Press again and the next matching occurrence is shown.
Shift+Enter
Ctrl+Shift+Enter
Insert Line Below / Insert Line Above
Insert a line above or below the current line.
Ctrl+/
Ctrl+\
Add Block Comment / Remove Block Comment
Comment in/out blocks of code with a key stroke.
Ctrl+M
Maximize Active View or Editor
Maximize the current view or editor at the expense of all other currently shown views. Press again to restore to normal view.
Ctrl+F6
Ctrl+F7
Ctrl+F8
Next Editor / Next View / Next Perspective
Learn these to switch among edited files, open views and perspectives.
Ctrl+Alt+Up
Ctrl+Alt+Down
Duplicate Lines / Copy Lines
Doesn't seem like it at first but a great shortcut once you learn to use it. Instead of select, copy and paste simply select and duplicate without affecting the clipboard.
Alt+/
Word Completion
This is excellent for code editing or writing plain help files with variables and other words having no English language equivalents. The word completion is based on the set of words already present in the current file.
Ctrl+I
Correct Indentation
Select a block of Java code or an entire class file and use this shortcut to correct its indentation.