JavaME: Convert String to camelCase

Question

What would be a simple implementation of a method to convert a String like "Hello there everyone" to "helloThereEveryone". In JavaME support for String and StringBuffer utility operations are quite limited.

Answer 1

Quick primitive implementation. I have no idea of restrictions of J2ME, so I hope it fits or it gives some ideas...

String str = "Hello, there, everyone?";

StringBuffer result = new StringBuffer(str.length());
String strl = str.toLowerCase();
boolean bMustCapitalize = false;
for (int i = 0; i < strl.length(); i++)
{
  char c = strl.charAt(i);
  if (c >= 'a' && c <= 'z')
  {
    if (bMustCapitalize)
    {
      result.append(strl.substring(i, i+1).toUpperCase());
      bMustCapitalize = false;
    }
    else
    {
      result.append(c);
    }
  }
  else
  {
    bMustCapitalize = true;
  }
}
System.out.println(result);

You can replace the convoluted uppercase append with:

result.append((char) (c - 0x20));

although it might seem more hackish.

Answer 2

With CDC, you have:

String.getBytes();//to convert the string to an array of bytes String.indexOf(int ch); //for locating the beginning of the words String.trim();//to remove spaces

For lower/uppercase you need to add(subtract) 32.

With these elements, you can build your own method.

Answer 3

private static String toCamelCase(String s) {
    String result = "";
    String[] tokens = s.split("_"); // or whatever the divider is
    for (int i = 0, L = tokens.length; i<L; i++) {
        String token = tokens[i];
        if (i==0) result = token.toLowerCase();
        else
            result += token.substring(0, 1).toUpperCase() +
                token.substring(1, token.length()).toLowerCase();
    }
    return result;
}

Answer 4

Suggestion:

May be if you can port one regexp library on J2ME, you could use it to strip spaces in your String...

Answer 5

Try following code

public static String toCamel(String str) {
    String rtn = str;
    rtn = rtn.toLowerCase();
    Matcher m = Pattern.compile("_([a-z]{1})").matcher(rtn);
    StringBuffer sb = new StringBuffer();
    while (m.find()) {
        m.appendReplacement(sb, m.group(1).toUpperCase());
    }
    m.appendTail(sb);
    rtn = sb.toString();
    return rtn;
}

Answer 6

I would suggest the following simple code:

    String camelCased = "";
    String[] tokens = inputString.split("\\s");
    for (int i = 0; i < tokens.length; i++) {
        String token = tokens[i];
        camelCased = camelCased + token.substring(0, 1).toUpperCase() + token.substring(1, token.length());
    }
    return camelCased;

Answer 7

I would do it like this:

private String toCamelCase(String s) {
    StringBuffer sb = new StringBuffer();
    String[] x = s.replaceAll("[^A-Za-z]", " ").replaceAll("\\s+", " ")
            .trim().split(" ");

    for (int i = 0; i < x.length; i++) {
        if (i == 0) {
            x[i] = x[i].toLowerCase();
        } else {
            String r = x[i].substring(1);
            x[i] = String.valueOf(x[i].charAt(0)).toUpperCase() + r;

        }
        sb.append(x[i]);
    }
    return sb.toString();
}

Answer 8

check this

import org.apache.commons.lang.WordUtils;

String camel = WordUtils.capitalizeFully('I WANT TO BE A CAMEL', new char[]{' '});

return camel.replaceAll(" ", "");