public class GetRecordsRequest extends AmazonWebServiceRequest implements Serializable, Cloneable
GetRecords operation
.
Gets data records from a shard.
Specify a shard iterator using the ShardIterator
parameter. The shard iterator specifies the position in the shard from
which you want to start reading data records sequentially. If there
are no records available in the portion of the shard that the iterator
points to, GetRecords
returns an empty list. Note that it
might take multiple calls to get to a portion of the shard that
contains records.
You can scale by provisioning multiple shards. Your application should
have one thread per shard, each reading continuously from its stream.
To read from a stream continually, call GetRecords
in a
loop. Use GetShardIterator to get the shard iterator to specify in the
first GetRecords
call. GetRecords
returns a
new shard iterator in NextShardIterator
.
Specify the shard iterator returned in
NextShardIterator
in subsequent calls to
GetRecords
.
Note that if the shard has been closed, the shard iterator
can't return more data and GetRecords
returns
null
in NextShardIterator
.
You can terminate the loop when the shard is closed, or
when the shard iterator reaches the record with the sequence number or
other attribute that marks it as the last record to process.
Each data record can be up to 50 KB in size, and each shard can read
up to 2 MB per second. You can ensure that your calls don't exceed the
maximum supported size or throughput by using the Limit
parameter to specify the maximum number of records that
GetRecords
can return. Consider your average record size
when determining this limit. For example, if your average record size
is 40 KB, you can limit the data returned to about 1 MB per call by
specifying 25 as the limit.
The size of the data returned by GetRecords
will vary
depending on the utilization of the shard. The maximum size of data
that GetRecords
can return is 10 MB. If a call returns 10
MB of data, subsequent calls made within the next 5 seconds throw
ProvisionedThroughputExceededException
.
If there is insufficient provisioned throughput on the
shard, subsequent calls made within the next 1 second throw
ProvisionedThroughputExceededException
.
Note that GetRecords
won't return any data
when it throws an exception. For this reason, we recommend that you
wait one second between calls to GetRecords
;
however, it's possible that the application will get
exceptions for longer than 1 second.
To detect whether the application is falling behind in processing, add
a timestamp to your records and note how long it takes to process
them. You can also monitor how much data is in a stream using the
CloudWatch metrics for write operations ( PutRecord
and
PutRecords
). For more information, see
Monitoring Amazon Kinesis with Amazon CloudWatch
in the Amazon Kinesis Developer Guide .
NOOP
Constructor and Description |
---|
GetRecordsRequest() |
Modifier and Type | Method and Description |
---|---|
GetRecordsRequest |
clone() |
boolean |
equals(Object obj) |
Integer |
getLimit()
The maximum number of records to return.
|
String |
getShardIterator()
The position in the shard from which you want to start sequentially
reading data records.
|
int |
hashCode() |
void |
setLimit(Integer limit)
The maximum number of records to return.
|
void |
setShardIterator(String shardIterator)
The position in the shard from which you want to start sequentially
reading data records.
|
String |
toString()
Returns a string representation of this object; useful for testing and
debugging.
|
GetRecordsRequest |
withLimit(Integer limit)
The maximum number of records to return.
|
GetRecordsRequest |
withShardIterator(String shardIterator)
The position in the shard from which you want to start sequentially
reading data records.
|
copyBaseTo, copyPrivateRequestParameters, getCustomRequestHeaders, getGeneralProgressListener, getReadLimit, getRequestClientOptions, getRequestCredentials, getRequestMetricCollector, putCustomRequestHeader, setGeneralProgressListener, setRequestCredentials, setRequestMetricCollector, withGeneralProgressListener, withRequestMetricCollector
public String getShardIterator()
Constraints:
Length: 1 - 512
public void setShardIterator(String shardIterator)
Constraints:
Length: 1 - 512
shardIterator
- The position in the shard from which you want to start sequentially
reading data records. A shard iterator specifies this position using
the sequence number of a data record in the shard.public GetRecordsRequest withShardIterator(String shardIterator)
Returns a reference to this object so that method calls can be chained together.
Constraints:
Length: 1 - 512
shardIterator
- The position in the shard from which you want to start sequentially
reading data records. A shard iterator specifies this position using
the sequence number of a data record in the shard.public Integer getLimit()
GetRecords
throws InvalidArgumentException
.
Constraints:
Range: 1 - 10000
GetRecords
throws InvalidArgumentException
.public void setLimit(Integer limit)
GetRecords
throws InvalidArgumentException
.
Constraints:
Range: 1 - 10000
limit
- The maximum number of records to return. Specify a value of up to
10,000. If you specify a value that is greater than 10,000,
GetRecords
throws InvalidArgumentException
.public GetRecordsRequest withLimit(Integer limit)
GetRecords
throws InvalidArgumentException
.
Returns a reference to this object so that method calls can be chained together.
Constraints:
Range: 1 - 10000
limit
- The maximum number of records to return. Specify a value of up to
10,000. If you specify a value that is greater than 10,000,
GetRecords
throws InvalidArgumentException
.public String toString()
toString
in class Object
Object.toString()
public GetRecordsRequest clone()
clone
in class AmazonWebServiceRequest
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