public StartSessionRequest withClientRequestToken(String clientRequestToken) {
        setClientRequestToken(clientRequestToken);
        return this;
    }
<p>
A unique case-sensitive string used to ensure the request to create the session is idempotent (executes only
once). If another <code>StartSessionRequest</code> is received, the same response is returned and another session
is not created. If a parameter has changed, an error is returned.
</p>
<important>
<p>
This token is listed as not required because Amazon Web Services SDKs (for example the Amazon Web Services SDK
for Java) auto-generate the token for users. If you are not using the Amazon Web Services SDK or the Amazon Web
Services CLI, you must provide this token or the action will fail.
</p>
</important>

@param clientRequestToken
       A unique case-sensitive string used to ensure the request to create the session is idempotent (executes
       only once). If another <code>StartSessionRequest</code> is received, the same response is returned and
       another session is not created. If a parameter has changed, an error is returned.</p> <important>
       <p>
       This token is listed as not required because Amazon Web Services SDKs (for example the Amazon Web Services
       SDK for Java) auto-generate the token for users. If you are not using the Amazon Web Services SDK or the
       Amazon Web Services CLI, you must provide this token or the action will fail.
       </p>
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-athena/src/main/java/com/amazonaws/services/athena/model/StartSessionRequest.java