first draft of cyclic year

see issue #638

calendar/src/main/java/net/time4j/calendar/CyclicYear.java

@@ -0,0 +1,151 @@
+/*
+ * -----------------------------------------------------------------------
+ * Copyright © 2013-2018 Meno Hochschild, <http://www.menodata.de/>
+ * -----------------------------------------------------------------------
+ * This file (CyclicYear.java) is part of project Time4J.
+ *
+ * Time4J is free software: You can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * Time4J is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Time4J. If not, see <http://www.gnu.org/licenses/>.
+ * -----------------------------------------------------------------------
+ */
+
+package net.time4j.calendar;
+
+import java.io.InvalidObjectException;
+import java.io.ObjectInputStream;
+import java.io.Serializable;
+
+
+/**
+ * <p>Represents the cyclic year used in East Asian calendars. </p>
+ *
+ * @author  Meno Hochschild
+ * @since   3.39/4.34
+ * @doctags.concurrency {immutable}
+ */
+/*[deutsch]
+ * <p>Repr&auml;sentiert das zyklische Jahr, das in ostasiatischen Kalendern verwendet wird. </p>
+ *
+ * @author  Meno Hochschild
+ * @since   3.39/4.34
+ * @doctags.concurrency {immutable}
+ */
+public final class CyclicYear
+    implements Comparable<CyclicYear>, Serializable {
+
+    //~ Statische Felder/Initialisierungen ------------------------------------
+
+    //~ Instanzvariablen ------------------------------------------------------
+
+    /**
+     * @serial  the number of cyclic year
+     */
+    private final int year;
+
+    //~ Konstruktoren ---------------------------------------------------------
+
+    private CyclicYear(int year) {
+        super();
+
+        if ((year < 1) || (year > 60)) {
+            throw new IllegalArgumentException("Out of range: " + year);
+        }
+
+        this.year = year;
+    }
+
+    //~ Methoden --------------------------------------------------------------
+
+    /**
+     * <p>Obtains an instance of cyclic year. </p>
+     *
+     * @param   yearOfCycle     year number in the range 1-60
+     * @return  CyclicYear
+     * @throws  IllegalArgumentException if the parameter is out of range
+     */
+    /*[deutsch]
+     * <p>Liefert eine Instanz eines zyklischen Jahres. </p>
+     *
+     * @param   yearOfCycle     year number in the range 1-60
+     * @return  CyclicYear
+     * @throws  IllegalArgumentException if the parameter is out of range
+     */
+    public static CyclicYear of(int yearOfCycle) {
+
+        return new CyclicYear(yearOfCycle);
+
+    }
+
+    /**
+     * <p>Obtains the associated year number in the range 1-60. </p>
+     *
+     * @return  int
+     */
+    /*[deutsch]
+     * <p>Liefert die Jahreszahl im Bereich 1-60. </p>
+     *
+     * @return  int
+     */
+    public int getNumber() {
+
+        return this.year;
+
+    }
+
+    @Override
+    public int compareTo(CyclicYear other) {
+
+        return (this.year - other.year);
+
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+
+        if (obj instanceof CyclicYear) {
+            return (this.year == ((CyclicYear) obj).year);
+        } else {
+            return false;
+        }
+
+    }
+
+    @Override
+    public int hashCode() {
+
+        return Integer.hashCode(this.year);
+
+    }
+
+    @Override
+    public String toString() {
+
+        return String.valueOf(this.year);
+
+    }
+
+    /**
+     * @serialData  Checks the consistency of deserialized data
+     * @param       in      object input stream
+     * @throws      InvalidObjectException if the year is not in range 1-60
+     */
+    private void readObject(ObjectInputStream in)
+        throws InvalidObjectException {
+
+        if ((year < 1) || (year > 60)) {
+            throw new InvalidObjectException("Out of range: " + this.year);
+        }
+
+    }
+
+}