JEdit does not support intelli-sense out of the box. There are plugins, but I'm not sure about their effectiveness and not available for Java.
One thing that he has out of the box, better than a jab in his teeth, automatically completes based on the words that are in all open buffers. This function is called Full Word, and the default key commitment to complete the word is ctrl + b . This feature is documented here .
There is a version with the TextAutocomplete plugin.
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