title: StringFormat for Java Boolean Operator
body: <p>I know its very simple question. but I would like to know the stringformat for boolean operator. 
  For example, below shows the string formats for integer, string and float. what could be for boolean operator true/false?</p>
  
  <pre><code>System.out.printf("The value of the float " +
                    "variable is %f, while " +
                    "the value of the " + 
                    "integer variable is %d, " +
                    "and the string is %s", 
                    floatVar, intVar, stringVar); 
  </code></pre>