public void setGameSessionArn(String gameSessionArn) {
        this.gameSessionArn = gameSessionArn;
    }
<p>
Identifier for the game session created by this placement request. This identifier is unique across all Regions.
This value isn't final until placement status is <code>FULFILLED</code>.
</p>

@param gameSessionArn
       Identifier for the game session created by this placement request. This identifier is unique across all
       Regions. This value isn't final until placement status is <code>FULFILLED</code>.
aws-java-sdk-gamelift/src/main/java/com/amazonaws/services/gamelift/model/GameSessionPlacement.java