static SimpleBody create(final byte[] body, final ContentType contentType) {
        Args.notNull(body, "Body");
        return new SimpleBody(body, null, contentType);
    }
Message body representation as a simple text string or an array of bytes.

@since 5.0
httpclient5/src/main/java/org/apache/hc/client5/http/async/methods/SimpleBody.java