[POO] aula05 ex1 added

1ano/2semestre/poo/src/aula05/DateYMD.java

@@ -0,0 +1,147 @@
+package aula05;
+
+import java.util.Scanner;
+
+public class DateYMD {
+    static boolean validMonth(int month) {
+        return month >= 1 && month <= 12;
+    }
+
+    static int monthDays(int month, int year) {
+        if (!validMonth(month))
+            return -1;
+        int[] daysPerMonth = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+        if (month == 2 && isLeapYear(year))
+            return 29;
+        return daysPerMonth[month - 1];
+    }
+
+    static boolean isLeapYear(int year) {
+        return year % 100 == 0 ? year % 400 == 0 : year % 4 == 0;
+    }
+
+    static boolean validDate(int day, int month, int year) {
+        return day >= 1 && day <= monthDays(month, year);
+    }
+
+    class Date {
+        private int day;
+        private int month;
+        private int year;
+
+        public Date(int day, int month, int year) {
+            if (!validDate(day, month, year))
+                throw new IllegalArgumentException("Invalid date");
+            this.day = day;
+            this.month = month;
+            this.year = year;
+        }
+
+        public void set(int day, int month, int year) {
+            if (!validDate(day, month, year))
+                throw new IllegalArgumentException("Invalid date");
+            this.day = day;
+            this.month = month;
+            this.year = year;
+        }
+
+        public int getDay() {
+            return day;
+        }
+
+        public int getMonth() {
+            return month;
+        }
+
+        public int getYear() {
+            return year;
+        }
+
+        public void increment() {
+            if (this.day < monthDays(this.month, this.year))
+                this.day++;
+            else if (this.month < 12) {
+                this.day = 1;
+                this.month++;
+            } else {
+                this.day = 1;
+                this.month = 1;
+                this.year++;
+            }
+        }
+
+        public void decrement() {
+            if (this.day > 1)
+                this.day--;
+            else if (this.month > 1) {
+                this.day = monthDays(this.month - 1, this.year);
+                this.month--;
+            } else {
+                this.day = 31;
+                this.month = 12;
+                this.year--;
+            }
+        }
+
+        public String toString() {
+            return String.format("%04d-%02d-%02d", year, month, day);
+        }
+    }
+}
+
+class TestDateYMD {
+    public static void main(String[] args) {
+        Scanner sin = new Scanner(System.in);
+        DateYMD.Date date = null;
+        while (true) {
+            System.out.println("Date operations:");
+            System.out.println("1 - Create date");
+            System.out.println("2 - Show current date");
+            System.out.println("3 - Increment date");
+            System.out.println("4 - Decrement date");
+            System.out.println("0 - Exit");
+            System.out.print("Option: ");
+            int option = sin.nextInt();
+            if (option == 0)
+                break;
+            switch (option) {
+                case 1:
+                    System.out.print("Day: ");
+                    int day = sin.nextInt();
+                    System.out.print("Month: ");
+                    int month = sin.nextInt();
+                    System.out.print("Year: ");
+                    int year = sin.nextInt();
+                    date = new DateYMD().new Date(day, month, year);
+                    System.out.println("Date created: " + date);
+                    break;
+                case 2:
+                    if (date == null) {
+                        System.out.println("Date not created");
+                        break;
+                    }
+                    System.out.println("Current date: " + date);
+                    break;
+                case 3:
+                    if (date == null) {
+                        System.out.println("Date not created");
+                        break;
+                    }
+                    date.increment();
+                    System.out.println("Date incremented: " + date);
+                    break;
+                case 4:
+                    if (date == null) {
+                        System.out.println("Date not created");
+                        break;
+                    }
+                    date.decrement();
+                    System.out.println("Date decremented: " + date);
+                    break;
+                default:
+                    System.out.println("Invalid option");
+            }
+        }
+        sin.close();
+    }
+}

1ano/2semestre/poo/src/aula05/README.md

@@ -6,9 +6,9 @@
 * [Slides](https://github.com/TiagoRG/uaveiro-leci/tree/master/1ano/2semestre/poo/slides/POO_04_Herança.pdf)
 
 ### Exercise List
-| Exercise Number | File Name                                                                                                            |
+| Exercise Number | File Name                                                                                                      |
-|-----------------|----------------------------------------------------------------------------------------------------------------------|
+|-----------------|----------------------------------------------------------------------------------------------------------------|
-|                 |                                                                                                                      |
+| 1               | [DateYMD.java](https://github.com/TiagoRG/uaveiro-leci/blob/master/1ano/2semestre/poo/src/aula05/DateYMD.java) |
 
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 *Pode conter erros, caso encontre algum, crie um* [*ticket*](https://github.com/TiagoRG/uaveiro-leci/issues/new)