I need help writing these two methods so i can compare them with mine

import java.io.File; import java.io.FileNotFoundException; import java.util.ArrayList;

/** * This program makes a concordance for a file or a String. * A concordance lists all the words that occur in the file or String, * along with all the line numbers on which each word occurs. * (Words of length less than 3 are omitted, "and" and "the" are omitted.) * Strip out all punctuation, except apostrophes that occur in the * middle of a word, i.e. lets, wed, etc. * * * */ public interface ConcordanceDataManagerInterface { /** * * Display the words in Alphabetical Order followed by a :, * followed by the line numbers in numerical order, followed by a newline * here's an example: * after: 129, 175 * agree: 185 * agreed: 37 * all: 24, 93, 112, 175, 203 * always: 90, 128 * * @param input a String (usually consist of several lines) to * make a concordance of * * @return an ArrayList of Strings. Each string has one word, * followed by a :, followed by the line numbers in numerical order, * followed by a newline. */ public ArrayList createConcordanceArray(String input); /** * Creates a file that holds the concordance * * @param input the File to read from * @param output the File to write to * * Following is an example: * * about: 24, 210 * abuse: 96 * account: 79 * acknowledged: 10 * * @return true if the concordance file was created successfully. * @throws FileNotFoundException if file not found */ public boolean createConcordanceFile(File input, File output) throws FileNotFoundException; }