8343236: Use @APinote and @implSpec in j.util.Currency

Reviewed-by: iris, lancea, bpb, naoto

Author: Justin Lu

src/java.base/share/classes/java/util/Currency.java

@@ -103,8 +103,8 @@
  * and/or minor unit are encountered, those entries are ignored and the remainder
  * of entries in file are processed.
  *
- * <p>
- * It is recommended to use {@link java.math.BigDecimal} class while dealing
+ * @apiNote
+ * It is recommended to use the {@link java.math.BigDecimal} class while dealing
  * with {@code Currency} or monetary values as it provides better handling of floating
  * point numbers and their operations.
  *
@@ -521,7 +521,8 @@ public String getCurrencyCode() {
      * {@linkplain Locale##def_locale_extension Unicode extensions},
      * the symbol returned from this method reflects
      * the value specified with that extension.
-     * <p>
+     *
+     * @implSpec
      * This is equivalent to calling
      * {@link #getSymbol(Locale)
      *     getSymbol(Locale.getDefault(Locale.Category.DISPLAY))}.
@@ -621,7 +622,8 @@ public String getNumericCodeAsString() {
      * the default {@link Locale.Category#DISPLAY DISPLAY} locale.
      * If there is no suitable display name found
      * for the default locale, the ISO 4217 currency code is returned.
-     * <p>
+     *
+     * @implSpec
      * This is equivalent to calling
      * {@link #getDisplayName(Locale)
      *     getDisplayName(Locale.getDefault(Locale.Category.DISPLAY))}.