CSC-220 HW7 Recursive Character Frequency Generator

CharacterData.java

/*
 * Name:  Prof. Antonio C. Silvestri (STCC)
 * Date:  11/12/2018
 * Course Number:  CSC-220
 * Course Name:  Data Structures and Algorithms
 * Problem Number: HW7
 * Email:  silvestri@stcc.edu
 * Description:  Recursive Character Frequency Generator 
 */

package charactercount;

public class CharacterData implements Comparable<CharacterData> {
	private char ch;
	private int count;
	
	public CharacterData(char ch, int count) {
		this.ch = ch;
		this.count = count;
	}

	public char getCh() {
		return ch;
	}

	public void setCh(char ch) {
		this.ch = ch;
	}

	public int getCount() {
		return count;
	}

	public void setCount(int count) {
		this.count = count;
	}

	public void addToCount(int number) {
		this.count += number;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ch;
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		CharacterData other = (CharacterData) obj;
		if (ch != other.ch)
			return false;
		return true;
	}

	@Override
	public String toString() {
		return String.format("%c:%d", this.ch, this.count);
	}

	@Override
	public int compareTo(CharacterData arg) {
		return this.ch - arg.ch; 
	}
	
}

CharacterFrequencyApp.java

/*
 * Name:  Prof. Antonio C. Silvestri (STCC)
 * Date:  11/12/2018
 * Course Number:  CSC-220
 * Course Name:  Data Structures and Algorithms
 * Problem Number: HW7
 * Email:  silvestri@stcc.edu
 * Description:  Recursive Character Frequency Generator 
 */

package charactercount;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class CharacterFrequencyApp {
	
	private static ArrayList<CharacterData> characterCount(String line) {
		if (line.equals(""))
			return new ArrayList<CharacterData>();
		ArrayList<CharacterData> frequency = characterCount(line.substring(1));
		int index = frequency.indexOf(new CharacterData(line.charAt(0), 0));
		if (index == -1)
			frequency.add(new CharacterData(line.charAt(0), 1));
		else
			frequency.get(index).addToCount(1);
		return frequency;		
	}
	
	//**********************************************
	
	private static void frequencyReport(ArrayList<CharacterData> frequency) {
		Collections.sort(frequency);
		for (CharacterData cd: frequency) {
			System.out.println(cd);
		}
	}
	
	//**********************************************

	private static void process(Scanner sc, String args[]) {
		System.out.print("Enter a string: ");
		String line = sc.nextLine();
		ArrayList<CharacterData> frequency = characterCount(line);
		frequencyReport(frequency);
	}
	
	//**********************************************

	private static boolean doThisAgain(Scanner sc, String prompt) {
		System.out.print(prompt);
		String doOver = sc.nextLine();
		return doOver.equalsIgnoreCase("Y");
	}
	
	//**********************************************
	
	public static void main(String args[]) {
		final String TITLE = "Character Frequency App V1.0";
		final String CONTINUE_PROMPT = "Do this again? [y/N] ";
		
		System.out.println("Welcome to " + TITLE);
		Scanner sc = new Scanner(System.in);
		do {
			process(sc, args);
		} while (doThisAgain(sc, CONTINUE_PROMPT));
		sc.close();
		System.out.println("Thank you for using " + TITLE);
	}

}