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- Writing code and don't know which methods an object of given class have? Eclipse has a nice feature called code completion (content assist), which makes coding really easy
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- Searching for a java class and don't know in which package it is? CTRL + SHIFT + T pops up a window where you can type the name of your java class and open it.
- Searching for a file (be it a .sql file or .properties or .java)? CTRL + SHIFT + R pops up a window where you can type a name of your file and open it.
- Having unresolved imports or just some imports more then needed in your java file? CTRL + SHIFT + O organizes the imports for you, importing the needed class if it finds it and deleting the unneeded ones.
- Searching for a method in a very long class? CTRL + O outlines the current class and you can type the name of the method and navigate to it straight.
- Having the line of code and wanting to navigate to it? just type the line in CTRL + L and go there.
- Wanting to know where in workspace a method of a class is called? having the cursor on desired method/property just hit CTRL + ALT + H or right-click on the method and click on Open Call hierarchy . a new window in perspective is opened where you can see who call the method (also the calling of the call, etc).
- Having a messy code? select part of code you want to format (CTRL+A for selecting all) and hitting CTRL + SHIFT + F formats the code according to your format settings.
- Searching for a word in a file and wanting to go match by match? select the word and CTRL + K finds the next occurring of the selected text in the file. CTRL + SHIFT + K finds the previous occurrence of the selected text in the file.
- Wanting to see line numbers? in menu Window -> Preferences -> General -> Editors -> Text Editors -> check Show Line Numbers.
- Wanting to see spaces and tabs? (you will see how messy the code is, mixing tabs and spaces!) in menu Window -> Preferences -> General -> Editors -> Text Editors -> check Show Whitespace Characters.
- Looking for a method/class/variable declaration Click and then F3 shows you the declaration.
The above listed shortcuts are what I use every day
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Other Eclipse shortcuts and tips: http://www.bristle.com/Tips/Eclipse.htm