有效地将字符串解析为 class object 在 java 中有 2 个浮点数

Question

I need to parse an input string into a new class object consisting of two floats. I do have a solution but it looks cumbersome. I wondered if there is a more elegant way to do it, esp. if the string splits only to 2 substrings and a cycle seems to be a bit of overkill?

my class:

public class Float2 {
    public float width;
    public float height;
}

my method to parse the input string into a class object:

 public Float2 parseStringToFloat2(String inputstring) {

            String[]  stringarray = inputstring.split(",");
            float[] floats = new float[2];
            for (int i = 0; i <2; ++i) {
                float number = Float.parseFloat(stringarray[i]);
                floats[i] = number;
            }
            return new Float2(floats[0], floats[1]);
        }

Answer 1

I do think the loop is an overkill if you know for sure there will by only 2 parts. Maybe try this:

public Float2 parseStringToFloat2(String inputstring){
            String[] stringarray = inputstring.split(",");
            try {
                return new Float2(Float.parseFloat(stringarray[0]), Float.parseFloat(stringarray[1]));
            } catch (Exception e) {
                // catch logic
            }
            return null;
        }

As said in a comment, you should also use try catch logic in case of a conversion error.

Answer 2

Another solution would be to use a Scanner . It is a more flexible solution if you need Locale-specific parsing (it uses the default locale without setting it, which could be problematic if a , is a decimal separator there). Also if you use a regex delim, the pattern can be precompiled to be faster.

public static Optional<Float2> parseStringToFloat2(String inputstring) {
    final Scanner in = new Scanner(inputstring).useLocale(Locale.US).useDelimiter(", ");
    // in.useDelimiter(Pattern.compile("\\s*,\\s*"));
    try {
        return Optional.of(new Float2(in.nextFloat(), in.nextFloat()));
    } catch (NoSuchElementException e) {
        return Optional.empty();
    }
}