StringScanner

This is a clone of Ruby's StringScanner from strscan.

It's not feature complete, but it has all the minimum scanning features expected.

Examples

scan

Tries to match with pattern at the current position. If there's a match, the scanner advances the “scan pointer” and returns the matched string. Otherwise, the scanner returns null.

import fr.blackteam.strscan.StringScanner;
import java.util.regex.Pattern;

var words = Pattern.compile("\\w+");
var spaces = Pattern.compile("\\s+");
var s = new StringScanner("This is an example string");

s.isEos();         // -> false

s.scan(words);     // -> "This"
s.scan(words);     // -> nil
s.scan(spaces);    // -> " "
s.scan(spaces);    // -> nil
s.scan(words);     // -> "is"
s.isEos();         // -> false

s.scan(spaces);    // -> " "
s.scan(words);     // -> "an"
s.scan(spaces);    // -> " "
s.scan(words);     // -> "example"
s.scan(spaces);    // -> " "
s.scan(words);     // -> "string"
s.isEos();         // -> true

s.scan(spaces);    // -> nil
s.scan(words);     // -> nil

scanUntil

Scans the string until the pattern is matched. Returns the substring up to and including the end of the match, advancing the scan pointer to that location. If there is no match, null is returned.

import fr.blackteam.strscan.StringScanner;
import java.util.regex.Pattern;

var s = new StringScanner("Fri Dec 12 1975 14:39");
s.scanUntil("1");  // -> "Fri Dec 1"
s.getPos();        // -> 9