Multi Clipboard gives you a clipboard for text- and source-code editor contents that holds multiple entries. You can collect some snippets by adding them to the Multi Clipboard and then paste any of them to where you need them.
You can configure the plug-in to save the contents of your Multi Clipboard to a file when Eclipse is closed. Contents are then reloaded when Eclipse is opened. You can even configure the plug-in to enable editing the contents of the Multi Clipboard.
Click on this link to get more detail: http://www.bastian-bergerhoff.com/eclipse/features/web/MultiClipboard/toc.html
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