How declara a method in my jsp code?

Question

I have the following method.
Somebody knows as there is to declare it in my jsp code?
Thanks.
public String reemplaza(String i,String ci,cf)
String o=i;
while(o.indexOf(ci)!=-1)
{ o=o.substring(0,indexOf(ci))+cf+o.substring(indexOf(ci)+ci.length(),o.length()); }
return o;
}

Answer 1

Compare the codes and you see the errors.
//Before(with errors)
public String reemplaza(String i,String ci,cf)
String o=i;
while(o.indexOf(ci)!=-1)
{ o=o.substring(0,indexOf(ci))+cf+o.substring(indexOf(ci)+ci.length(),o.length()); }
return o;
//After(with no errors):
public String reemplaza(String i,String ci,String cf)
String o=i;
while(o.indexOf(ci)!=-1)
{ o=o.substring(0,o.indexOf(ci))+cf+o.substring(o.indexOf(ci)+ci.length(),o.length()); }
return o;