It's very easy to start working on eclipse. This is the best tutorial i found to guide, how to start: http://www.vogella.de/articles/Eclipse/article.html and to open an existing project. go to new-> java project-> same name as of your existing project ->create from existing ( radio button). point to the location where it's located-> next->finish. if you have an ant file, better to open it with ant file. go for new->other->java ->java project from existing using ant->browse the file and just give the project name and finish. Your project is ready but before that you'll need to install ant in your system and set it's environment variable.
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