Split Strings separated by an artbitrary character

Question

Say we would like to write a method to receive entire book in a string and an arbitrary single-character delimiter to separate strings and return an array of strings. I came up with the following implementation (Java).(suppose no consecutive delimiter etc)

ArrayList<String> separater(String book, char delimiter){
ArrayList<String> ret = new ArrayList<>();
String word ="";

    for (int i=0; i<book.length(), ++i){
        if (book.charAt(i)!= delimiter){
            word += book.charAt(i);
        } else {
            ret.add(word);
            word = "";
        }
    }
    return ret;
}

Question: I wonder if there is any way to leverage String.split() for shorter solutions? Its because I could not find a general way of defining a general regex for an arbitrary character delimiter.

String.split("\\.") if the delimiter is '.'
String.split("\\s+"); if the delimiter is ' ' // space character 

That measn I cold not find a general way of generating the input regex of method split() from the input character delimiter. Any suggestions?

Answer 1

String[] array = string.split(Pattern.quote(String.valueOf(delimiter)));

That said, The Guava Splitter is much more versatile and well-behaving than String.split() .

And a note on your method: concatenating to a String in a loop is very inefficient. As Strings are immutable, it produces a lot of temporary Strings and StringBuilders. You should use a StringBuilder instead.