It would be a lot better to use a JTable for this (especially if you are planning on making this information editable by the user), but all you'd have to do is surround the data with tabs (\t) and end each row with a newline (\n). The problem occurs when one or more of your data strings exceeds the space allowed by the tabs and your columns are no longer aligned. You don't have this problem with a JTable.
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