Appends the specified character sequence to this {@code Appendable}.
<p> Depending on which class implements the character sequence
{@code csq}, the entire sequence may not be appended. For
instance, if {@code csq} is a {@link java.nio.CharBuffer} then
the subsequence to append is defined by the buffer's position and limit.
@param csq
The character sequence to append. If {@code csq} is
{@code null}, then the four characters {@code "null"} are
appended to this Appendable.
Appends the specified character sequence to this {@code Appendable}.
<p> Depending on which class implements the character sequence {@code csq}, the entire sequence may not be appended. For instance, if {@code csq} is a {@link java.nio.CharBuffer} then the subsequence to append is defined by the buffer's position and limit.
@param csq The character sequence to append. If {@code csq} is {@code null}, then the four characters {@code "null"} are appended to this Appendable.
@return A reference to this {@code Appendable}
@throws IOException If an I/O error occurs