What is the difference between -HeapDumpOnOutOfMemoryError and +HeapDumpOnOutOfMemoryError options?

Question

In Oracle's official doc HeapDumpOnOutOfMemoryError option specified with plus and minus sign. I'm just curious what do they stand for since it's not explained in official user guide

Answer 1

From the page you cited:

Some command-line options use the HotSpot implementation format; that is, you must place the colon (:) between the -XX and the option name followed by a the necessary operator to indicate enabling (+) or disabling (-) the new hash function.