Your task is to write methods in JAVA for a program that analyzes an arbitrary number of strings passed as arguments on the command line. Like with many large projects, some of the code has been written for you, and you are not allowed to change it. Instead, you are constrained to filling in certain methods, that must operate to fulfill not only individual-method unit tests, but tests that cover larger swaths of code.

As an example, consider that a user calls the program from the terminal without any arguments:

$ java edu.wit.cs.comp1050.PA3a

Please supply at least one argument at the command line.

That is, you will be writing verification that there is at least one argument supplied! Now lets consider a valid example:

$ java edu.wit.cs.comp1050.PA3a hello world!

Arguments (2, no duplication): hello world!

Length: total=11, avg=6

Shortest (5):

Longest (6):

Average (6):

Now you can see the program in action, but perhaps not all the pieces, so another:

$ java edu.wit.cs.comp1050.PA3a I see a little silhouetto of a man Scaramouche Scaramouche will you do the Fandango Thunderbolt and lightning very very fright\'ning me

Arguments (22, has duplication): I see a little silhouetto of a man Scaramouche Scaramouche will you do the Fandango Thunderbolt and lightning very very fright'ning me

Length: total=113, avg=5

Shortest (1): first=, last=

Longest (11): first=, last=

Average (5): none

The program produces outputs that counts the overall and average length (rounded to the nearest integer), checks for duplication, and outputs the first and last arguments that have the shortest, longest, and average lengths.

The following methods have been implemented completely, and you are NOT to change them:

• main: validates input, produces program output
• firstOfLength/lastOfLength: call a common utility method (that you WILL implement) to find an element of a particular length
• firstLongestElement/lastLongestElement: call a common utility method (that you WILL implement) to find the longest element
• firstShortestElement/lastShortestElement: call a common utility method (that you WILL implement) to find the shortest element

The remaining methods must be implemented by you, as guided by the Javadoc and JUnit tests.

package edu.wit.cs.comp1050; //TODO: document this class public class PA3a { /** * Error to output if no command-line arguments supplied */ public static final String ERR_USAGE = "Please supply at least one argument at the command line."; // DO NOT CHANGE /** * Opening quote character */ public static final char QUOTE_CHAR_OPEN = '<'; // DO NOT CHANGE /** * Closing quote character */ public static final char QUOTE_CHAR_CLOSE = '>'; // DO NOT CHANGE /** * Finds an element in a non-empty * array that has minimal length. * If first is true, the first such; * otherwise the last. * * @param a input array * @param first if true, return the first minimal-length element; otherwise the last * @return element in a that has maximal length */ private static String findShortest(String[] a, boolean first) { return null; // replace with your code } /** * Finds the first of the elements of a * supplied array that have the minimal * length * * @param a input array (assumed non-empty) * @return first element in a that has minimal length */ public static String firstShortestElement(String[] a) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findShortest(a, true); } /** * Finds the last of the elements of a * supplied array that have the minimal * length * * @param a input array (assumed non-empty) * @return last element in a that has minimal length */ public static String lastShortestElement(String[] a) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findShortest(a, false); } /** * Finds an element in a non-empty * array that has maximal length. * If first is true, the first such; * otherwise the last. * * @param a input array * @param first if true, return the first maximal-length element; otherwise the last * @return element in a that has maximal length */ private static String findLongest(String[] a, boolean first) { return null; // replace with your code } /** * Finds the first of the elements of a * supplied array that have the maximal * length * * @param a input array (assumed non-empty) * @return first element in a that has maximal length */ public static String firstLongestElement(String[] a) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findLongest(a, true); } /** * Finds the last of the elements of a * supplied array that have the maximal * length * * @param a input array (assumed non-empty) * @return last element in a that has maximal length */ public static String lastLongestElement(String[] a) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findLongest(a, false); } /** * Returns an element with a supplied length * (if it exists, else null). If first is true, * the first such element; else the last. * * @param a input array * @param len length of element for which to search * @param first if true searches for first; else searches for last * @return element with length len in a according to first */ private static String findOfLength(String[] a, int len, boolean first) { return null; // replace with your code } /** * Returns the first element of a * supplied array that has the * supplied length exactly, or * null if not found * * @param a input array * @param len length of element for which to search * @return first element with length len, or null if not found */ public static String firstOfLength(String[] a, int len) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findOfLength(a, len, true); } /** * Returns the last element of a * supplied array that has the * supplied length exactly, or * null if not found * * @param a input array * @param len length of element for which to search * @return last element with length len, or null if not found */ public static String lastOfLength(String[] a, int len) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// return findOfLength(a, len, false); } /** * Returns the sum of the lengths * of all the elements in the * supplied string array * * @param a input array * @return summation over the length of all strings in a */ public static int sumOfElementLengths(String[] a) { return 0; // replace with your code } /** * Given a sum and count, returns * the average as an integer * naturally rounded * * @param sum elements summed * @param count count of elements * @return rounded average of sum and count */ public static int averageAsInt(int sum, int count) { return 0; // replace with your code } /** * Returns true if the supplied array * has two elements with the same contents * (not necessarily same identity) * * @param a array to examine * @return true if a contains duplicate elements */ public static boolean hasDuplicates(String[] a) { return false; // replace with your code } /** * Utility method to quote a supplied * string using supplied open/close * characters * * @param s string to quote * @param cOpen character before the string * @param cClose character after the string * @return quoted string */ public static String flexibleQuote(String s, char cOpen, char cClose) { return ""; // replace with your code } /** * Utility method for printing the first and last * Strings from a list. Rules: * - If both are null, return "none" * - If either are null, return the other (quoted) * - If the same string is provided twice (identity, not content); return either (quoted) * - Otherwise return "first=quoted(sFirst), last=quoted(sLast)" * * Characters for quoting are supplied as arguments * * @param sFirst first string * @param sLast last string * @param cOpen open character for quoting * @param cClose close character for quoting * @return string according to the rules above */ public static String oneOrBothOrNone(String sFirst, String sLast, char cOpen, char cClose) { return ""; // replace with your code } /** * Utility method to print (to the terminal) * an array of Strings given something before * the list, something after, and something * between each element * * @param a elements * @param sBefore what to print before the list * @param sSep what to print between each element * @param sAfter what to print after the list */ public static void printWithSeparator(String[] a, String sBefore, String sSep, String sAfter) { // replace with your code } /** * Returns true if command-line arguments * were supplied; false otherwise * * @param args program arguments * @return true if input is of non-zero length */ public static boolean validArgs(String[] args) { return false; // replace with your code } /** * Outputs a small analysis of strings * supplied as command-line arguments * to the program * * @param args command-line arguments */ public static void main(String[] args) { ////////////////////////////////// // !! DO NOT CHANGE THIS METHOD !! ////////////////////////////////// if (!validArgs(args)) { System.out.printf("%s%n", ERR_USAGE); System.exit(1); } // System.out.printf("Arguments (%d, %s duplication):", args.length, (hasDuplicates(args))?("has"):("no")); printWithSeparator(args, " ", " ", String.format("%n")); // final int lSum = sumOfElementLengths(args); final int lAvg = averageAsInt(lSum, args.length); System.out.printf("Length: total=%d, avg=%d%n", lSum, lAvg); // final String fShortest = firstShortestElement(args); final String lShortest = lastShortestElement(args); System.out.printf("Shortest (%d): %s%n", fShortest.length(), oneOrBothOrNone(fShortest, lShortest, QUOTE_CHAR_OPEN, QUOTE_CHAR_CLOSE)); // final String fLongest = firstLongestElement(args); final String lLongest = lastLongestElement(args); System.out.printf("Longest (%d): %s%n", fLongest.length(), oneOrBothOrNone(fLongest, lLongest, QUOTE_CHAR_OPEN, QUOTE_CHAR_CLOSE)); // final String fAverage = firstOfLength(args, lAvg); final String lAverage = lastOfLength(args, lAvg); System.out.printf("Average (%d): %s%n", lAvg, oneOrBothOrNone(fAverage, lAverage, QUOTE_CHAR_OPEN, QUOTE_CHAR_CLOSE)); } }