Java - Write code to Returns the longest common prefix for two Strings or "" if no prefix is shared

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Requirements

Write code to Returns the longest common prefix for two Strings or "" if no prefix is shared

Demo

//package com.book2s;

public class Main {
    public static void main(String[] argv) {
        String one = "book2s.com";
        String two = "book2s.com";
        System.out.println(longestCommonPrefix(one, two));
    }//from ww w .  jav a  2s .c  o  m

    /**
     * Returns the longest common prefix for two Strings or <tt>""</tt> if no prefix is shared
     *
     * @param one The one String
     * @param two The other String
     *
     * @return The longest common prefix, or ""
     */
    public static String longestCommonPrefix(String one, String two) {
        if (one.equals(two)) {
            return one;
        }
        if (one.equals("") || two.equals("")) {
            return "";
        }

        String currentPrefix = "";
        int size = 0;
        while (one.startsWith(currentPrefix)
                && two.startsWith(currentPrefix)) {
            size++;
            currentPrefix = one.substring(0, size);
        }
        return one.substring(0, size - 1);
    }
}

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