In java how to get substring from a string till a character c?

Question

I have a string (which is basically a file name following a naming convention) abc.def.ghi

I would like to extract the substring before the first

Answer 1

Here is code which returns a substring from a String until any of a given list of characters:

/**
 * Return a substring of the given original string until the first appearance
 * of any of the given characters.
 * 

 * e.g. Original "ab&cd-ef&gh"
 * 1. Separators {'&', '-'}
 * Result: "ab"
 * 2. Separators {'~', '-'}
 * Result: "ab&cd"
 * 3. Separators {'~', '='}
 * Result: "ab&cd-ef&gh"
 *
 * @param original   the original string
 * @param characters the separators until the substring to be considered
 * @return the substring or the original string of no separator exists
 */
public static String substringFirstOf(String original, List characters) {
    return characters.stream()
            .map(original::indexOf)
            .filter(min -> min > 0)
            .reduce(Integer::min)
            .map(position -> original.substring(0, position))
            .orElse(original);
}