Replace one sub-string with desired String

class StringDemo19
{
static String replace(String s1, String s2, String s3)
{
s1 += ' ';
int i;
String x[] = s1.split(s2), result="";
result += x[0];
for(i=1;i<x.length;i++)
{
result += s3 + x[i];
}
return result;
}
public static void main(String... s)
{
System.out.println(replace("i am an indian", "am", "love"));
}
}