Morse Code decoder problem with looping through String

I'm trying to write a simple Morse Code Decoder. It takes a Morse Code string and converts it into the English. I'm struggling with one problem, my code does not decode the last character. I guess I know where the problem is, but I can't resolve it on my own, so I hope you could help me.
For example if I'm trying to decode "-... . --. .. -. - .... . . -. -.." which is "Begin The End" it decodes it to "Begin the En".

public class Main {
public static void main(String[] args) {
String codeToDecode = "-... . --. .. -.  - .... .  . -. -.."; //  any random Morse code
String decode = ""; 
int flag = 0;
codeToDecode=codeToDecode.replace(' ','/'); 
Map<String, String> vocabulary = new HashMap<>(); //This is my "vocabulary" 
vocabulary.put(".-", "a");
// it goes on this way, i'll cut next letters to save space. 
...
vocabulary.put("--..", "z");
if(codeToDecode.length()<3){
decode += vocabulary.get(codeToDecode);
}
if(codeToDecode=="...---..."){
decode="SOS";
}
for (int i = 0; i <codeToDecode.length(); i++) {
if (codeToDecode.charAt(i) == '/') { // Here must be the problem. '/' is the blank space. My code "decodes" parts from space to space, but in the end of the string there is no blank space so it ignores last letter. I tried using "||i==codeToDecode.length()" in if statement, but it didn't work.
decode += vocabulary.get(codeToDecode.substring(flag, i));
flag = i + 1;
} if(codeToDecode.charAt(i)=='/'&&codeToDecode.charAt(i+1)=='/'){
decode+=" ";
i+=2;
flag+=2;
}
}
decode=decode.toUpperCase();
System.out.println(decode);
}
}

I understand there are many problems to come with my approach( I'm sure there is a better way to complete this task) but I'm trying to finish this one on my own without looking at the ready examples. I hope my code is clear as well as my explanations. Thank you in advance.

Peace and Love!

java is 0-indexed. You sort of know this; your for loop goes from 0 to i < codeToDecode.length().

So this: for (int i = 0; i < 10; i++) will print.. 0 through 9. It never prints 10. This is why it works: A string of length 10 will give up its last character if you write: str.charAt(9). charAt(9) gets you the 10th character (because .charAt(0) gets you the first).

So, if you write: if (i == codeToDecode.length()), that's never going to happen. At the final char position, i is 9, and codeToDecode.length() is 10. Try if (i == codeToDecode.length() - 1).

NB: Some code style tips:

• codeToDecode is quite unwieldy. Maybe just code is fine.
• Fill that dictionary in a separate method, so much cleaner.
• Don't include explicit cornercases (such as: If input size below 3) if not needed, and it shouldn't be needed here. Your main loop will get the job done, once you fix the bug.
• Note the actual morse code for SOS is any subsequence of an endlessly repeating SOSOSOSOSO.... that contains at least ...---.... For example, .---...---...---...--- is also an SOS. If you want to repeatedly call out an SOS, you don't do 6 dots, just keep repeating 3 dashes and 3 dots forever. The idea is also that a potential rescuer will eventually get in range and starts picking up the signal at some unknown point in your endless sequence. With that mindset it should be obvious why SOS works this way.