public RunInstancesRequest withClientToken(String clientToken) {
        setClientToken(clientToken);
        return this;
    }
<p>
Unique, case-sensitive identifier you provide to ensure the idempotency of the request. If you do not specify a
client token, a randomly generated token is used for the request to ensure idempotency.
</p>
<p>
For more information, see <a
href="https://docs.aws.amazon.com/AWSEC2/latest/APIReference/Run_Instance_Idempotency.html">Ensuring
Idempotency</a>.
</p>
<p>
Constraints: Maximum 64 ASCII characters
</p>

@param clientToken
       Unique, case-sensitive identifier you provide to ensure the idempotency of the request. If you do not
       specify a client token, a randomly generated token is used for the request to ensure idempotency.</p>
       <p>
       For more information, see <a
       href="https://docs.aws.amazon.com/AWSEC2/latest/APIReference/Run_Instance_Idempotency.html">Ensuring
       Idempotency</a>.
       </p>
       <p>
       Constraints: Maximum 64 ASCII characters
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/RunInstancesRequest.java