prints characters in one case, but in another it returns integers. Why is that?

Hell again,

so here is the new one. The Java Tutorial that I am following says the following:

"Write a program that computes your initials from your full name and displays them."

so I wrote the following, making up a name for it and using examples previously encountered in the tutorial:

Code:

---

public class MyInitials {
        public static void main(String[] args){
                String myName = "Roger Justice";
               
                int gap = myName.indexOf(' ');
                System.out.println(gap);
               
                System.out.println(myName.charAt(0));
               
                System.out.print((myName.charAt(0) + (myName.charAt(myName.indexOf(' ')+1))));
        }
}

---

When I use the following, I get this output. So I get a number of 156 instead of RJ:
(oh, feel free to ignore the first System.out.println. I was just tinkering with things.

Code:

---

----jGRASP exec: java MyInitials

5
R
156
 ----jGRASP: operation complete.

---

However if split the output over two lines, I get the desired outcome:
CODE:

Code:

---

public class MyInitials {
        public static void main(String[] args){
                String myName = "Roger Justice";
               
                int gap = myName.indexOf(' ');
                System.out.println(gap);
               
                System.out.println(myName.charAt(0));
               
                System.out.print((myName.charAt(0)));
                System.out.println((myName.charAt(myName.indexOf(' ')+1)));
        }
}

---

I get this output, the desired one:

Code:

---

----jGRASP exec: java MyInitials

5
R
RJ

 ----jGRASP: operation complete.

---

I don't understand why this happens.

ASCII value for R is 82, for J is 74. 82 + 74 = 156.

You get that result because you are using addition. Since chars are represented by integer values under the hood it applies integer addition instead of concatenation like Strings. So to achieve your desired ouput try using different print statements for each initial or use a StringBuilder to create a new String.

Quote:

---

Originally Posted by Junky

ASCII value for R is 82, for J is 74. 82 + 74 = 156.

You get that result because you are using addition. Since chars are represented by integer values under the hood it applies integer addition instead of concatenation like Strings. So to achieve your desired ouput try using different print statements for each initial or use a StringBuilder to create a new String.

---

Got it. Thank you!

So here is a different version:

Code:

---

public class MyInitials2 {
        public static void main(String[] args) {
       
                String myName = "Roger Justice";
                StringBuffer myInitials = new StringBuffer();
                int length = myName.length();
               
                for (int i = 0; i<length; i++) {
                        if (Character.isUpperCase(myName.charAt(i))) {
                                myInitials.append(myName.charAt(i));
                        }
                }
                System.out.println("My initials are: "+ myInitials);
        }
}

---

This is adapted from the answer provided in the tutorial. My question is how was I supposed to know that? Am I supposed to look through the entire Java API? It's not searchable is it? Is that a normal habit to develop?

As a n00b your solution would have been what I would have done. Only as you become more experienced will you learn about other classes such as StringBuffer or as I suggested StringBuilder which is basically the same class. The only difference is that one is synchronised and one isn't.

Just a nitpick. The sugggested solution will not work if the name was "roger justice". Using charAt is a bit more robust. Also you can use the split method instead of using indexOf to find the space. This method is even better as it can handle multiple names such as "James Robert David Smith".

Quote:

---

Originally Posted by Junky

Just a nitpick. The sugggested solution will not work if the name was "roger justice". Using charAt is a bit more robust. Also you can use the split method instead of using indexOf to find the space. This method is even better as it can handle multiple names such as "James Robert David Smith".

---

It worked. It returned RJ. Am I missing something? What are you called the suggested solution?

He meant that that method only works on capital first letters, it would be much better to print the first letter regardless.

Check out the split API, it takes a regex and splits a string into an array of strings, so the string "bob mike Johnny" would split into an array where each element contains a name. you can then loop through the array getting each character with charAt, or substring. This approach would work on an infinite amount of words in the name and would continue working regardless of case of letters.

I can't seem to get it to work. I tried:

System.out.println(split(string)); and I am getting a cannot find symbol error on the split.

Oh and I have not yet covered regular expressions...I had to google regex. :(sweat):

The split method is in the String class so you need to call it on an instance of String. It returns a String array so you cannot just print it (well you can but you won't get anything meaningful displayed). Try assigning it to a variable.

Code:

---

String text = "one two three";
String[] words = text.split(" "); //split on a space

---

That will give you an array with "one" as the first element, "two" as the second and "three" as the third.

Don't let regex scare you, for split you can generally use very general versions, split on words or spaces by simply using a space or character. Split is a method of the string class, you call it on an instance of a string with a regex as an argument.
" ", "abc", "[a-z]" are all valid regexes, the first matches to any spaces, the second splits on the word abc, and the third splits on characters from a to z.

Code:

---

String a = "ex am pl es";
String[] ex = a.split(" ");
for(int i = 0; i < ex.length; ++i){
  System.out.print(ex[i]);
}

---

Thank you....and thank you for improving the world...one idiot at a time!

ETA:This was in response to junky!

Quote:

---

Originally Posted by sunde887

Don't let regex scare you, for split you can generally use very general versions, split on words or spaces by simply using a space or character. Split is a method of the string class, you call it on an instance of a string with a regex as an argument.
" ", "abc", "[a-z]" are all valid regexes, the first matches to any spaces, the second splits on the word abc, and the third splits on characters from a to z.

Code:

---

String a = "ex am pl es";
String[] ex = a.split(" ");
for(int i = 0; i < ex.length; ++i){
  System.out.print(ex[i]);
}

---

---

Oh I get it now. This is right now. Thanks.!

OT

Does anyone else see only the top left hand quadrant for some of the smilies?

:(y): :(n): :^): :frusty: :beer: :smash: :beer: :smash: :focus: :coffee:

I see the full smilies for all the ones you just posted.

I meant in the reply box where you can select them. the ones in the above post was so that I could see them.