Question

What to submit: your answers to exercises 1, and 2 and separate the codes to each question.

1. Create a MyTime class which is designed to contain objects representing times in 12-hour clock format. Eg: 7:53am, 10:20pm, 12:00am (= midnight), 12:00pm (= noon). You can assume the user will enter times in the format given by the previous examples.

Provide a default constructor, a set method which is given a String (eg: “7:53am”), a getHours method, a getMinutes method and a boolean isAm method. Also provide a method for returning a string “morning”, “afternoon”, “evening” or “night” appropriate (in your opinion) to the time.

Please see the NOTE below concerning input validation and exception.

2. Write a client program for MyTime which loops around getting strings from the user representing times and responding with a greeting such as “good morning” as appropriate. The user should enter the string “quit” to exit the program.

EXAMPLE run of client:

USER: 2:07 pm

PROGRAM: good afternoon

USER: 10:71 am

PROGRAM: that’s not a valid time, please re-enter

USER: 14:30am

PROGRAM: that’s not a valid time, please re-enter

USER: 10:21am

PROGRAM: good morning

USER: 7:00 pm

PROGRAM: good evening

NOTE for questions 1 and 2: the set method for MyTime should detect input strings which do not represent valid times. An exception should be thrown in such a case. Clients (such as the one you are writing for question 2) will have to handle (or catch) the exceptions. Thus you will have to also write your own exception class which can be used by MyTime and the client class.

Answer 1

Assumption:

1) You are asking to write classes in Java (If any other, then let me know in comments)
2) night (from 12:00 am to 5:59 am), morning (from 6:00 am to 11:59 am), afternoon (from 12:00 pm to 6:00 pm), evening (from 6:00 pm to 11:59 pm)

I have made three classes

1) Main.java: class with main method for getting input from user. (client program)
2) MyTime.java: class for time
3) InvalidTimeException.java: exception class for Invalid time

Below are the links of code. I'm pasting code here also

Main.java --> https://pastebin.com/NB109rFN
MyTime.java --> https://pastebin.com/nH0gSNV8
InvalidTimeException --> https://pastebin.com/NZA302Ja

Main.java

import java.util.*;
public class Main
{
        public static void main(String[] args) {
                Scanner sc = new Scanner(System.in);
                while(true){
                    System.out.println("USER: ");
                    String time = sc.nextLine().replaceAll("\\s","");
                    if(time.equals("quit"))  break;
                    MyTime obj = new MyTime();
                    System.out.println("PROGRAM: ");
                    try{
                        obj.setTime(time);
                        System.out.println("good "+obj.getGreeting());
                    }
                    catch(Exception e){
                        System.out.println("that’s not a valid time, please re-enter");
                    }
                }
        }
}

MyTime.java

import java.util.*;
import java.time.*;
public class MyTime{
    private String time;
    private int hour;
    private int minute;
    private String format;
    public void setTime(String time) throws InvalidTimeException{
        try{
            this.time = time;
            int idx = 0;
            while(idx<time.length() && ! Character.isLetter(time.charAt(idx))){
                idx++;
            }
            this.format = time.substring(idx,time.length());
            String[] str = time.substring(0,idx).split(":");
            this.hour = Integer.parseInt(str[0]);
            this.minute = Integer.parseInt(str[1]);
            if(!(format.equals("am") || format.equals("pm"))){
                throw new InvalidTimeException("that’s not a valid time, please re-enter");
            }
            else if(hour>12 || hour<1 || minute>59 || minute<0){
                throw new InvalidTimeException("that’s not a valid time, please re-enter");
            }
        }
        catch(Exception e){
            throw new InvalidTimeException("that’s not a valid time, please re-enter");
        }
    }
    public int getHours(){
        return hour;
    }
    public int getMinutes(){
        return minute;
    }
    public boolean isAm(){
        return format.equals("am");
    }
    public String getGreeting(){
        if (format.equals("am")){
            if((hour>=1 && hour<6 && minute<=59 && minute>=0) || (hour==12 && minute<=59 && minute>0)){
                return "night";
            }
            else return "morning";
        }
        else{
            if((hour>=1 && hour<6 && minute<=59 && minute>=0) || (hour==12 && minute<=59 && minute>0)){
                return "afternoon";
            }
            else return "evening";
        }
    }
}

InvalidTimeException.java

class InvalidTimeException extends Exception{
    InvalidTimeException(String msg){
        super(msg);
    }
}

I hope you got your desired answer. Have a good day. :)