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Eclipse 3.3 - and I guess also other Java IDEs - provides a Code Formatter option according the Java Convention by Sun. You may import the Eclipse Code Formatter Profile Java Conventions without tabs, which differs from Eclipse's build-in Java Convention Formatter Profile only by the Indentation Tab policy modified from Mixed to Spaces only. In order to import within Eclipse 3.3, select Window - > Preferences - > Java - > Code Style - > Formatter - -> Import.
For more information, see Coding Standards.
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