Clean Code

.next()
);
} catch (
NoSuchElementException
e) {
errorCode = ErrorCode.MISSING_STRING;
throw new ArgsException();
}
}
These were simple changes that kept all the tests passing. Now we can start moving the 
set
functions down into the appropriate derivatives. First, I need to make the following change
in
setArgument
:
private boolean setArgument(char argChar) throws ArgsException {
ArgumentMarshaler m = marshalers.get(argChar);
if (m == null)
return false;
try {
if (m instanceof BooleanArgumentMarshaler)
setBooleanArg(m);
else if (m instanceof StringArgumentMarshaler)
setStringArg(m);
else if (m instanceof IntegerArgumentMarshaler)
setIntArg(m);

---

233
String Arguments
else
return false;
} catch (ArgsException e) {
valid = false;
errorArgumentId = argChar;
throw e;
}
return true;
}
This change is important because we want to completely eliminate the 
if-else
chain.
Therefore, we needed to get the error condition out of it. 
Now we can start to move the 
set
functions. The 
setBooleanArg
function is trivial, so
we’ll prepare that one first. Our goal is to change the 
setBooleanArg
function to simply for-
ward to the 
BooleanArgumentMarshaler
.
private boolean setArgument(char argChar) throws ArgsException {
ArgumentMarshaler m = marshalers.get(argChar);
if (m == null)
return false;
try {
if (m instanceof BooleanArgumentMarshaler)
setBooleanArg(m, 
currentArgument
);
else if (m instanceof StringArgumentMarshaler)
setStringArg(m);
else if (m instanceof IntegerArgumentMarshaler)
setIntArg(m);
} catch (ArgsException e) {
valid = false;
errorArgumentId = argChar;
throw e;
}
return true;
}
---
private void setBooleanArg(ArgumentMarshaler m,