public static void batchProcessDocument()

in document-ai/src/main/java/documentai/v1/BatchProcessDocument.java [62:173]
68 lines of code
5 McCabe index (conditional complexity)

  public static void batchProcessDocument(
      String projectId,
      String location,
      String processorId,
      String gcsInputUri,
      String gcsOutputBucketName,
      String gcsOutputUriPrefix)
      throws IOException, InterruptedException, TimeoutException, ExecutionException {
    // Initialize client that will be used to send requests. This client only needs
    // to be created
    // once, and can be reused for multiple requests. After completing all of your
    // requests, call
    // the "close" method on the client to safely clean up any remaining background
    // resources.
    String endpoint = String.format("%s-documentai.googleapis.com:443", location);
    DocumentProcessorServiceSettings settings =
        DocumentProcessorServiceSettings.newBuilder().setEndpoint(endpoint).build();
    try (DocumentProcessorServiceClient client = DocumentProcessorServiceClient.create(settings)) {
      // The full resource name of the processor, e.g.:
      // projects/project-id/locations/location/processor/processor-id
      // You must create new processors in the Cloud Console first
      String name =
          String.format("projects/%s/locations/%s/processors/%s", projectId, location, processorId);

      GcsDocument gcsDocument =
          GcsDocument.newBuilder().setGcsUri(gcsInputUri).setMimeType("application/pdf").build();

      GcsDocuments gcsDocuments = GcsDocuments.newBuilder().addDocuments(gcsDocument).build();

      BatchDocumentsInputConfig inputConfig =
          BatchDocumentsInputConfig.newBuilder().setGcsDocuments(gcsDocuments).build();

      String fullGcsPath = String.format("gs://%s/%s/", gcsOutputBucketName, gcsOutputUriPrefix);
      GcsOutputConfig gcsOutputConfig = GcsOutputConfig.newBuilder().setGcsUri(fullGcsPath).build();

      DocumentOutputConfig documentOutputConfig =
          DocumentOutputConfig.newBuilder().setGcsOutputConfig(gcsOutputConfig).build();

      // Configure the batch process request.
      BatchProcessRequest request =
          BatchProcessRequest.newBuilder()
              .setName(name)
              .setInputDocuments(inputConfig)
              .setDocumentOutputConfig(documentOutputConfig)
              .build();

      OperationFuture<BatchProcessResponse, BatchProcessMetadata> future =
          client.batchProcessDocumentsAsync(request);

      // Batch process document using a long-running operation.
      // You can wait for now, or get results later.
      // Note: first request to the service takes longer than subsequent
      // requests.
      System.out.println("Waiting for operation to complete...");
      future.get();

      System.out.println("Document processing complete.");

      Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
      Bucket bucket = storage.get(gcsOutputBucketName);

      // List all of the files in the Storage bucket.
      Page<Blob> blobs = bucket.list(Storage.BlobListOption.prefix(gcsOutputUriPrefix + "/"));
      int idx = 0;
      for (Blob blob : blobs.iterateAll()) {
        if (!blob.isDirectory()) {
          System.out.printf("Fetched file #%d\n", ++idx);
          // Read the results

          // Download and store json data in a temp file.
          File tempFile = File.createTempFile("file", ".json");
          Blob fileInfo = storage.get(BlobId.of(gcsOutputBucketName, blob.getName()));
          fileInfo.downloadTo(tempFile.toPath());

          // Parse json file into Document.
          FileReader reader = new FileReader(tempFile);
          Document.Builder builder = Document.newBuilder();
          JsonFormat.parser().merge(reader, builder);

          Document document = builder.build();

          // Get all of the document text as one big string.
          String text = document.getText();

          // Read the text recognition output from the processor
          System.out.println("The document contains the following paragraphs:");
          Document.Page page1 = document.getPages(0);
          List<Document.Page.Paragraph> paragraphList = page1.getParagraphsList();
          for (Document.Page.Paragraph paragraph : paragraphList) {
            String paragraphText = getText(paragraph.getLayout().getTextAnchor(), text);
            System.out.printf("Paragraph text:%s\n", paragraphText);
          }

          // Form parsing provides additional output about
          // form-formatted PDFs. You must create a form
          // processor in the Cloud Console to see full field details.
          System.out.println("The following form key/value pairs were detected:");

          for (Document.Page.FormField field : page1.getFormFieldsList()) {
            String fieldName = getText(field.getFieldName().getTextAnchor(), text);
            String fieldValue = getText(field.getFieldValue().getTextAnchor(), text);

            System.out.println("Extracted form fields pair:");
            System.out.printf("\t(%s, %s))", fieldName, fieldValue);
          }

          // Clean up temp file.
          tempFile.deleteOnExit();
        }
      }
    }
  }