Question

Suppose I have an array of int, float, string etc. Is there any utility API (e.g. Commons, Guava) that will give me a comma separated string?

Like so,

int[] a = {1,2,3,4,5}. 
String s = magicAPI.getCSV(a); // s == "1,2,3,4,5";

Answer 1

I’ve used OpenCSV in the past.

StringWriter stringWriter = new StringWriter();
int[] a = {1,2,3,4,5};
String[] b = new String[a.length];
for ( int i = 0; i < a.length; i++) {
    b[i] = a[i];
}
CSVWriter csvWriter = new CSVWriter(stringWriter, ",");
csvWriter.writeNext(b);

However, for such a trivial example you might want to just use the a StringBuilder and a for loop