+ * @param ch {@inheritDoc}
+ * @return {@inheritDoc}
+ * @throws IOException {@inheritDoc}
+ */
+ @Override
+ public abstract Appendable append(char ch) throws IOException;
+
+ /**
+ * {@inheritDoc}
+ * @param seq {@inheritDoc}
+ * @return {@inheritDoc}
+ * @throws IOException {@inheritDoc}
+ */
+ @Override
+ public abstract Appendable append(CharSequence seq) throws IOException;
+
+ /**
+ * {@inheritDoc}
+ * @param seq {@inheritDoc}
+ * @param start {@inheritDoc}
+ * @param end {@inheritDoc}
+ * @return {@inheritDoc}
+ * @throws IOException {@inheritDoc}
+ */
+ @Override
+ public abstract Appendable append(CharSequence seq, int start, int end)
+ throws IOException;
+
+ /**
+ * {@inheritDoc}