public ActivityResponse withStart(String start) {
        setStart(start);
        return this;
    }
<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.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-pinpoint/src/main/java/com/amazonaws/services/pinpoint/model/ActivityResponse.java