package com.mindprod.example;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * test indexOfRegex to search a string for the first instance of a given pattern.
 * <p/>
 * Prepared with IntelliJ Idea.
 *
 * @author Roedy Green, Canadian Mind Products, based on an example posted by Knute Johnson
 * @version 1.0, 2008-01-29
 */
public class TestIndexOfRegex
    {
// ------------------------------ FIELDS ------------------------------

    /**
     * regex pattern to look for, in this case whitespace
     */
    private static final Pattern lookFor = Pattern.compile( "\\s+" );
// -------------------------- PUBLIC STATIC METHODS --------------------------

    /**
     * Scan a string for the first occurence of some regex Pattern.
     *
     * @param lookFor the pattern to look for
     * @param lookIn  the String to scan.
     * @return offset relative to start of lookIn where it first found the pattern, -1 if not found.
     */
    @SuppressWarnings( { "SameParameterValue", "WeakerAccess" } )
    public static int indexOfRegex( String lookIn,
                                    Pattern lookFor )
        {
        Matcher m = lookFor.matcher( lookIn );
        if ( m.find() )
            {
            return m.start();
            }
        else
            {
            return -1;
            }
        }

// --------------------------- main() method ---------------------------

    public static void main( String[] args )
        {
        String lookIn = "The quick brown fox jumped\n"
                        + "over the lazy dog's back.";
        System.out.println( indexOfRegex( lookIn, lookFor ) );
        // prints 3
        }
    }