Merge pull request #25 from jskimdev/branch-Model

Add dateofbirth class

src/main/java/seedu/address/model/person/DateOfBirth.java

@@ -0,0 +1,76 @@
+package seedu.address.model.person;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.commons.util.AppUtil.checkArgument;
+
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeParseException;
+
+/**
+ * Represents a Patient's date of birth.
+ * Guarantees: immutable; is valid as declared in {@link #isValidDateOfBirth(String)}
+ */
+public class DateOfBirth {
+
+    public static final String MESSAGE_CONSTRAINTS =
+            "Date of birth should only contain numeric values in dd/MM/yyyy or yyyy-MM-dd format, and it should not "
+                    + "be left blank";
+
+    public static final DateTimeFormatter inputFormat1 = DateTimeFormatter.ofPattern("d/M/yyyy");
+    public static final DateTimeFormatter inputFormat2 = DateTimeFormatter.ofPattern("yyyy-M-d");
+    public static final DateTimeFormatter outputFormat = DateTimeFormatter.ofPattern("yyyy-M-d");
+    public final LocalDate dateOfBirth;
+
+    /**
+     * Constructs a {@code DateOfBirth}.
+     *
+     * @param dateOfBirth A valid date of birth.
+     */
+    public DateOfBirth(String dateOfBirth) {
+        requireNonNull(dateOfBirth);
+        checkArgument(isValidDateOfBirth(dateOfBirth), MESSAGE_CONSTRAINTS);
+        this.dateOfBirth = parseDateOfBirth(dateOfBirth);
+    }
+
+    /**
+     * Returns true if a given string is a valid date of birth.
+     */
+    public static boolean isValidDateOfBirth(String test) {
+        return parseDateOfBirth(test) == null ? false : true;
+    }
+
+    /**
+     * Parse String date of birth into LocalDate.
+     *
+     * @param dateOfBirthString date of birth input.
+     * @return date of birth in LocalDate type.
+     */
+    public static LocalDate parseDateOfBirth(String dateOfBirthString) {
+        String cleanDateString = dateOfBirthString.strip();
+        DateTimeFormatter inputFormat = determineInputFormat(cleanDateString);
+        LocalDate dateOfBirth = null;
+
+        try {
+            dateOfBirth = LocalDate.parse(cleanDateString, inputFormat);
+            return dateOfBirth;
+        } catch (DateTimeParseException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Determines in which format the date of birth is input.
+     *
+     * @return the input format of String date of birth.
+     */
+    private static DateTimeFormatter determineInputFormat(String dateOfBirth) {
+        boolean isInputFromat1 = dateOfBirth.split("/").length > 1;
+        return isInputFromat1 ? inputFormat1 : inputFormat2;
+    }
+
+    @Override
+    public String toString() {
+        return dateOfBirth.format(outputFormat);
+    }
+}