I have to remove all vowels from a string using a for loop.

I have this declaration so I can just call VOWELS.

public static final String VOWELS = "aeiouAEIOU";

I'm just not sure how to return the string with no vowels in it but keep the vowel if starts the word.

This is what I have so far:

public static String stringCompress(String msg){

    String rtn = "";
    for(int i = 1; i < msg.length(); i  ){
        if(Character.isWhitespace(i)){
            rtn  = (char)(msg.charAt(i - 1);
        }
        else if(VOWELS.contains(msg.valueOf(i))){
            rtn  = msg.charAt(i);
        }
    }
    return rtn;
}        

but it's not returning what I need it to. its returning [be a r, if]

I am just really confused. Any suggestions would help.

CodePudding user response：

Removing vowels from a string unless the vowel starts the word using a for loop

You are making several mistakes.

• you don't want to use valueOf. Use charAt()
• As easy way to determine start of word is to save the previous character for testing as a space. So initialize it to a space.
• then if the previous char was not a space (i.e. not start of word) and the current character is a vowel, ignore it.
• otherwise append it to the return string.
• continue until the loop is done (which should start at 0 and not 1).

String test = "Animal    Horse   Elephant Dog cat ";
System.out.println(stringCompress(test));

prints

Anml    Hrs   Elphnt Dg ct 

• Use a StringBuilder to house the result
• lastChar is used to determine if it was preceded by a white space.

public static String stringCompress(String msg) {
    StringBuilder sb = new StringBuilder();
    char lastChar = ' ';
    for (int i = 0; i < msg.length(); i  ) {
        char c = msg.charAt(i);
        if (!VOWELS.contains(c "")
                || Character.isWhitespace(lastChar)) {
            sb.append(c);
        }
        lastChar = c;
    }
    return sb.toString();
}

CodePudding user response：

You can try using StringBuilder :

public static String stringCompress(String msg) {
    StringBuilder rtn = new StringBuilder("");
    for (int i = 0; i < msg.length(); i  ) {
        if (Character.isWhitespace(i) || !VOWELS.contains(msg.charAt(i)   "")) {
            rtn.append(msg.charAt(i));
        }
    }
    return rtn.toString();
}

CodePudding user response：

Try this, look at the isWhitespace line, maybe that is your problem:

public static String stringCompress(String msg){

    String rtn = "";
    for(int i = 1; i < msg.length(); i  ){
        if(Character.isWhitespace(msg.valueOf(i))){
            rtn  = (char)(msg.charAt(i - 1);
        }
        else if(VOWELS.contains(msg.valueOf(i))){
            rtn  = msg.charAt(i);
        }
    }
    return rtn;
}