Wrap a series of buttons with .btn in .btn-group.
<!DOCTYPE HTML>
<html>
<head>
<link href="http://java2s.com/style/bootstrap.min.css" rel="stylesheet">
<!-- w ww. j a v a2 s .c o m-->
<script src="http://java2s.com/style/jquery-1.8.0.min.js"></script>
<script src="http://java2s.com/style/bootstrap.min.js"></script>
</head>
<body style='margin:20px;'>
<div class="btn-group">
<button type="button" class="btn btn-default">Left</button>
<button type="button" class="btn btn-default">Middle</button>
<button type="button" class="btn btn-default">Right</button>
</div>
</body>
</html>