System.getProperties(key)

Hello,

Where can I find a list of "key" values for the above method call? In particular I want to find the key for the "TAB character"

Thank you

Code:

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        Properties props = System.getProperties();
        Enumeration<?> e = props.propertyNames();
        while(e.hasMoreElements()) {
            System.out.println(e.nextElement());
        }

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