8304840: Dangling CharacterCodingException in a few javadoc descriptions

Reviewed-by: alanb, iris, rriggs, jpai

Author: naotoj

src/java.base/share/classes/java/nio/charset/Charset-X-Coder.java.template

@@ -793,6 +793,15 @@ public abstract class Charset$Coder$ {
      *          the current unmappable-character action is {@link
      *          CodingErrorAction#REPORT}
      *
+     * @throws  CharacterCodingException
+     *          {@code MalformedInputException} if the $itype$ sequence starting at the
+     *          input buffer's current position is $notLegal$ and the current
+     *          malformed-input action is {@code CodingErrorAction.REPORT};
+     *          {@code UnmappableCharacterException} if the $itype$ sequence starting at
+     *          the input buffer's current position cannot be mapped to an
+     *          equivalent $otype$ sequence and the current unmappable-character
+     *          action is {@code CodingErrorAction.REPORT}
+     *
      * @throws  OutOfMemoryError
      *          If the output $otype$ buffer for the requested size of the input
      *          $itype$ buffer cannot be allocated

src/java.base/share/classes/java/nio/charset/CoderResult.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -264,6 +264,11 @@ public static CoderResult unmappableForLength(int length) {
      * @throws  UnmappableCharacterException
      *          If this object represents an unmappable-character error; the
      *          exception's length value will be that of this object
+     *
+     * @throws  CharacterCodingException
+     *          {@code MalformedInputException} if this object represents a
+     *          malformed-input error; {@code UnmappableCharacterException}
+     *          if this object represents an unmappable-character error
      */
     public void throwException()
         throws CharacterCodingException