JavaMail requires an InputStreamSource that creates a fresh stream for every call.

邮件增加附件时候，报错JavaMail requires an InputStreamSource that creates a fresh stream for every call.

  InputStreamResource inputStreamResource = new InputStreamResource(new URL(url).openStream());
        mimeMessageHelper.addAttachment(
                "wsktn.docx", inputStreamResource
        );

解决方式,使用IOUtils.toByteArray 读取后，ByteArrayResource包装解决此问题

        ByteArrayResource byteArrayResource = new ByteArrayResource(IOUtils.toByteArray(new URL(url).openStream()));
              mimeMessageHelper.addAttachment(
                "wsktn.docx", byteArrayResource 
        );