Examples of com.amazonaws.services.dynamodbv2.model.ScanRequest.withSegment()

com.amazonaws.services.dynamodbv2.model.ScanRequest.withSegment()

For a parallel Scan request, Segment identifies an individual segment to be scanned by an application worker.

Segment IDs are zero-based, so the first segment is always 0. For example, if you want to scan a table using four application threads, the first thread would specify a Segment value of 0, the second thread would specify 1, and so on.

The value of LastEvaluatedKey returned from a parallel Scan request must be used as ExclusiveStartKey with the same Segment ID in a subsequent Scan operation.

The value for Segment must be greater than or equal to 0, and less than the value provided for TotalSegments.

If you specify Segment, you must also specify TotalSegments.

Returns a reference to this object so that method calls can be chained together.

Constraints:
Range: 0 - 4095
@param segment For a parallel Scan request, Segment identifies anindividual segment to be scanned by an application worker.

The value of LastEvaluatedKey returned from a parallel Scan request must be used as ExclusiveStartKey with the same Segment ID in a subsequent Scan operation.

The value for Segment must be greater than or equal to 0, and less than the value provided for TotalSegments.

If you specify Segment, you must also specify TotalSegments. @return A reference to this updated object so that method calls can be chained together.

      if (totalSegments < 1)
      throw new IllegalArgumentException("Parallel scan should have at least one scan segment.");
      List<ScanRequest> parallelScanRequests= new LinkedList<ScanRequest>();
        for (int segment = 0; segment < totalSegments; segment++) {
          ScanRequest scanRequest = createScanRequestFromExpression(clazz, scanExpression, config);
          parallelScanRequests.add(scanRequest.withSegment(segment).withTotalSegments(totalSegments));
        }
        return parallelScanRequests;
    }


    private <T> QueryRequest  createQueryRequestFromExpression(Class<T> clazz, DynamoDBQueryExpression<T> queryExpression, DynamoDBMapperConfig config) {

        if (totalSegments < 1)
            throw new IllegalArgumentException("Parallel scan should have at least one scan segment.");
        List<ScanRequest> parallelScanRequests= new LinkedList<ScanRequest>();
        for (int segment = 0; segment < totalSegments; segment++) {
            ScanRequest scanRequest = createScanRequestFromExpression(clazz, scanExpression, config);
            parallelScanRequests.add(scanRequest.withSegment(segment).withTotalSegments(totalSegments));
        }
        return parallelScanRequests;
    }


    private <T> QueryRequest  createQueryRequestFromExpression(Class<T> clazz, DynamoDBQueryExpression<T> queryExpression, DynamoDBMapperConfig config) {

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