OnJava8-Examples/verifying/StringInverter4.java
2016-08-19 08:21:09 -06:00

30 lines
941 B
Java

// verifying/StringInverter4.java
// (c)2016 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
// {java StringInverterTest StringInverter4}
import static java.lang.Character.*;
public class StringInverter4 implements StringInverter {
static final String allowed =
"abcdefghijklmnopqrstuvwxyz ,." +
"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
public String invert(String str) {
if(str.length() > 25)
throw new RuntimeException("argument too long!");
String result = "";
for(int i = 0; i < str.length(); i++) {
char c = str.charAt(i);
if(allowed.indexOf(c) == -1)
throw new RuntimeException(c + " Not allowed");
result += isUpperCase(c) ?
toLowerCase(c) :
toUpperCase(c);
}
return result;
}
}
/* Output:
StringInverter4 has 0 FAILURES:
*/