如何使用信封to -java从docusign下载签名文档

ApiClient apiClient = new ApiClient();
apiClient.setBasePath("https://demo.docusign.net/restapi");
apiClient.addDefaultHeader("Authorization", "Bearer YOUR_API_KEY");

EnvelopesApi envelopesApi = new EnvelopesApi(apiClient);
EnvelopeDefinition envelopeDefinition = new EnvelopeDefinition();
envelopeDefinition.setEmailSubject("请签署文件");
envelopeDefinition.setEmailBlurb("请在指定位置签署文件。");
envelopeDefinition.setDocuments(Arrays.asList(
    new Document().documentId("1").name("文件1.pdf").fileExtension("pdf").documentBase64(Base64.encodeBase64String(fileContent))
));

Signer signer = new Signer();
signer.setEmail("signer@example.com");
signer.setName("签署者姓名");
signer.setRecipientId("1");
signer.setRoutingOrder("1");
signer.setTabs(new Tabs());
signer.getTabs().setSignHereTabs(Arrays.asList(
    new SignHere().documentId("1").pageNumber("1").xPosition("100").yPosition("100")
));
envelopeDefinition.setRecipients(new Recipients());
envelopeDefinition.getRecipients().setSigners(Arrays.asList(signer));

EnvelopeSummary envelopeSummary = envelopesApi.createEnvelope("accountId", envelopeDefinition);
envelopesApi.createRecipientView("accountId", envelopeSummary.getEnvelopeId(),
    new RecipientViewRequest().returnUrl("http://www.example.com/return-url").authenticationMethod("email"),
    false);

byte[] signedDocument = envelopesApi.getDocument("accountId", envelopeSummary.getEnvelopeId(), "1");