public java.util.List<String> getImpression() {
        return impression;
    }
<p>
A list of item IDs that represents the sequence of items you have shown the user. For example,
<code>["itemId1", "itemId2", "itemId3"]</code>. Provide a list of items to manually record impressions data for
an event. For more information on recording impressions data, see <a href=
"https://docs.aws.amazon.com/personalize/latest/dg/recording-events.html#putevents-including-impressions-data"
>Recording impressions data</a>.
</p>

@return A list of item IDs that represents the sequence of items you have shown the user. For example,
        <code>["itemId1", "itemId2", "itemId3"]</code>. Provide a list of items to manually record impressions
        data for an event. For more information on recording impressions data, see <a href=
        "https://docs.aws.amazon.com/personalize/latest/dg/recording-events.html#putevents-including-impressions-data"
        >Recording impressions data</a>.
aws-java-sdk-personalizeevents/src/main/java/com/amazonaws/services/personalizeevents/model/Event.java