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For more on tuning Eclipse JVM heap size, you can refer to this IBM article : http://www-128.ibm.com/developerworks/websphere/library/techarticles/0204_searle/searle.html
Getting Rid of Annoying Tabs
You can set up your Eclipse so that indentations are done in tabs rather than spaces. See convert spaces to tabs. In older versions of Eclipse, the button is "Show" rather than "Edit". Here is a sample screenshot 
If you want some scripts to help you check and clean up tabs in your files, go to http://www.opensourcestrategies.com/ofbiz/downloads.php. I'm told by the real Unix gurus that "this takes one line in sed." Yeah, I've heard that one before...
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Using local XSD's when no internet connection is available
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