public void setStart(String start) {
        this.start = start;
    }
<p>
The actual start time, in ISO 8601 format, of the activity.
</p>

@param start
       The actual start time, in ISO 8601 format, of the activity.
aws-java-sdk-pinpoint/src/main/java/com/amazonaws/services/pinpoint/model/ActivityResponse.java