public static String toString(final InputStream input, final Charset encoding)
			throws IOException {
		try (StringBuilderWriter sw = new StringBuilderWriter()) {
			copy(input, sw, encoding);
			return sw.toString();
		}
	}
Gets the contents of an <code>InputStream</code> as a String using the specified
character encoding.
<p>
This method buffers the input internally, so there is no need to use a
<code>BufferedInputStream</code>.
</p>
@param input the <code>InputStream</code> to read from
@param encoding the encoding to use, null means platform default
@return the requested String
@throws NullPointerException if the input is null
@throws java.io.IOException if an I/O error occurs
@since 2.3
spring-cloud-alibaba-starters/spring-cloud-alibaba-commons/src/main/java/com/alibaba/cloud/commons/io/IOUtils.java