You need to enclose that in <%! %> as follows:
<%!
public String getQuarter(int i){
String quarter;
switch(i){
case 1: quarter = "Winter";
break;
case 2: quarter = "Spring";
break;
case 3: quarter = "Summer I";
break;
case 4: quarter = "Summer II";
break;
case 5: quarter = "Fall";
break;
default: quarter = "ERROR";
}
return quarter;
}
%>
You can then invoke the function within scriptlets or expressions:
<%
out.print(getQuarter(4));
%>
or
<%= getQuarter(17) %>