/*
* Copyright 2010-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package com.amazonaws.services.kinesis.model;
import java.io.Serializable;
import com.amazonaws.AmazonWebServiceRequest;
/**
* <p>
* Gets data records from an Amazon Kinesis stream's shard.
* </p>
* <p>
* Specify a shard iterator using the <code>ShardIterator</code> 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, <a>GetRecords</a>
* returns an empty list. Note that it might take multiple calls to get to a
* portion of the shard that contains records.
* </p>
* <p>
* You can scale by provisioning multiple shards per stream while considering
* service limits (for more information, see <a href=
* "http://docs.aws.amazon.com/kinesis/latest/dev/service-sizes-and-limits.html"
* >Streams Limits</a> in the <i>Amazon Kinesis Streams Developer Guide</i>).
* Your application should have one thread per shard, each reading continuously
* from its stream. To read from a stream continually, call <a>GetRecords</a> in
* a loop. Use <a>GetShardIterator</a> to get the shard iterator to specify in
* the first <a>GetRecords</a> call. <a>GetRecords</a> returns a new shard
* iterator in <code>NextShardIterator</code>. Specify the shard iterator
* returned in <code>NextShardIterator</code> in subsequent calls to
* <a>GetRecords</a>. Note that if the shard has been closed, the shard iterator
* can't return more data and <a>GetRecords</a> returns <code>null</code> in
* <code>NextShardIterator</code>. 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.
* </p>
* <p>
* Each data record can be up to 1 MB 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 <code>Limit</code> parameter to
* specify the maximum number of records that <a>GetRecords</a> can return.
* Consider your average record size when determining this limit.
* </p>
* <p>
* The size of the data returned by <a>GetRecords</a> varies depending on the
* utilization of the shard. The maximum size of data that <a>GetRecords</a> can
* return is 10 MB. If a call returns this amount of data, subsequent calls made
* within the next 5 seconds throw
* <code>ProvisionedThroughputExceededException</code>. If there is insufficient
* provisioned throughput on the shard, subsequent calls made within the next 1
* second throw <code>ProvisionedThroughputExceededException</code>. Note that
* <a>GetRecords</a> won't return any data when it throws an exception. For this
* reason, we recommend that you wait one second between calls to
* <a>GetRecords</a>; however, it's possible that the application will get
* exceptions for longer than 1 second.
* </p>
* <p>
* To detect whether the application is falling behind in processing, you can
* use the <code>MillisBehindLatest</code> response attribute. You can also
* monitor the stream using CloudWatch metrics and other mechanisms (see <a
* href=
* "http://docs.aws.amazon.com/kinesis/latest/dev/monitoring.html">Monitoring
* </a> in the <i>Amazon Kinesis Streams Developer Guide</i>).
* </p>
* <p>
* Each Amazon Kinesis record includes a value,
* <code>ApproximateArrivalTimestamp</code>, that is set when a stream
* successfully receives and stores a record. This is commonly referred to as a
* server-side timestamp, whereas a client-side timestamp is set when a data
* producer creates or sends the record to a stream (a data producer is any data
* source putting data records into a stream, for example with
* <a>PutRecords</a>). The timestamp has millisecond precision. There are no
* guarantees about the timestamp accuracy, or that the timestamp is always
* increasing. For example, records in a shard or across a stream might have
* timestamps that are out of order.
* </p>
*/
public class GetRecordsRequest extends AmazonWebServiceRequest implements Serializable {
/**
* <p>
* 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.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Length: </b>1 - 512<br/>
*/
private String shardIterator;
/**
* <p>
* 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, <a>GetRecords</a>
* throws <code>InvalidArgumentException</code>.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Range: </b>1 - 10000<br/>
*/
private Integer limit;
/**
* <p>
* 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.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Length: </b>1 - 512<br/>
*
* @return <p>
* 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.
* </p>
*/
public String getShardIterator() {
return shardIterator;
}
/**
* <p>
* 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.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Length: </b>1 - 512<br/>
*
* @param shardIterator <p>
* 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.
* </p>
*/
public void setShardIterator(String shardIterator) {
this.shardIterator = shardIterator;
}
/**
* <p>
* 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.
* </p>
* <p>
* Returns a reference to this object so that method calls can be chained
* together.
* <p>
* <b>Constraints:</b><br/>
* <b>Length: </b>1 - 512<br/>
*
* @param shardIterator <p>
* 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.
* </p>
* @return A reference to this updated object so that method calls can be
* chained together.
*/
public GetRecordsRequest withShardIterator(String shardIterator) {
this.shardIterator = shardIterator;
return this;
}
/**
* <p>
* 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, <a>GetRecords</a>
* throws <code>InvalidArgumentException</code>.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Range: </b>1 - 10000<br/>
*
* @return <p>
* 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,
* <a>GetRecords</a> throws <code>InvalidArgumentException</code>.
* </p>
*/
public Integer getLimit() {
return limit;
}
/**
* <p>
* 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, <a>GetRecords</a>
* throws <code>InvalidArgumentException</code>.
* </p>
* <p>
* <b>Constraints:</b><br/>
* <b>Range: </b>1 - 10000<br/>
*
* @param limit <p>
* 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,
* <a>GetRecords</a> throws <code>InvalidArgumentException</code>
* .
* </p>
*/
public void setLimit(Integer limit) {
this.limit = limit;
}
/**
* <p>
* 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, <a>GetRecords</a>
* throws <code>InvalidArgumentException</code>.
* </p>
* <p>
* Returns a reference to this object so that method calls can be chained
* together.
* <p>
* <b>Constraints:</b><br/>
* <b>Range: </b>1 - 10000<br/>
*
* @param limit <p>
* 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,
* <a>GetRecords</a> throws <code>InvalidArgumentException</code>
* .
* </p>
* @return A reference to this updated object so that method calls can be
* chained together.
*/
public GetRecordsRequest withLimit(Integer limit) {
this.limit = limit;
return this;
}
/**
* Returns a string representation of this object; useful for testing and
* debugging.
*
* @return A string representation of this object.
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("{");
if (getShardIterator() != null)
sb.append("ShardIterator: " + getShardIterator() + ",");
if (getLimit() != null)
sb.append("Limit: " + getLimit());
sb.append("}");
return sb.toString();
}
@Override
public int hashCode() {
final int prime = 31;
int hashCode = 1;
hashCode = prime * hashCode
+ ((getShardIterator() == null) ? 0 : getShardIterator().hashCode());
hashCode = prime * hashCode + ((getLimit() == null) ? 0 : getLimit().hashCode());
return hashCode;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (obj instanceof GetRecordsRequest == false)
return false;
GetRecordsRequest other = (GetRecordsRequest) obj;
if (other.getShardIterator() == null ^ this.getShardIterator() == null)
return false;
if (other.getShardIterator() != null
&& other.getShardIterator().equals(this.getShardIterator()) == false)
return false;
if (other.getLimit() == null ^ this.getLimit() == null)
return false;
if (other.getLimit() != null && other.getLimit().equals(this.getLimit()) == false)
return false;
return true;
}
}