There are a number of possible ways to achieve this depending on the desired result.
You Could...
Use a GridLayout
which will allow you to add components into a single column. The downside to this is the width of each component will be the width of the parent container and each component will be given an equal amount of the height (divided amongst the components);
sidepanel.setLayout(new GridLayout(0, 1));
sidepanel.add(newgame);
sidepanel.add(ticketView);
sidepanel.add(moveView);
sidepanel.add(turn);
sidepanel.add(round);
You Could...
Use a GridBagLayout
which will allow you to control how components fill there column
sidepanel.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
// One component per row...
gbc.gridwidth = GridBagConstraints.REMAINDER;
// Fill the available column space, this does not mean
// fill to fit the available parent container width though
gbc.fill = GridBagConstraints.HORIZONTAL;
sidepanel.add(newgame, gbc);
sidepanel.add(ticketView, gbc);
sidepanel.add(moveView, gbc);
sidepanel.add(turn, gbc);
sidepanel.add(round, gbc);
The drawback to this is is that, by default, the GridBagLayout
will align all it's components to the center position of the container. There are tricks you can employ to change this, but it's a little messy
You Could...
Use the VertcialLayout
from SwingX libraries