With row selections enabled, clicking on any cell selects the entire row containing that cell. This also applies to columns. With cell selections enabled, rectangular blocks of cells can be selected. 
    JTable table = new JTable();
    
    // Enable row selection (default)
    table.setColumnSelectionAllowed(false);
    table.setRowSelectionAllowed(true);
    
    // Enable column selection
    table.setColumnSelectionAllowed(true);
    table.setRowSelectionAllowed(false);
    
    // Enable cell selection
    table.setColumnSelectionAllowed(true);
    table.setRowSelectionAllowed(true);

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