public AlarmHistoryItem withHistoryData(String historyData) {
        setHistoryData(historyData);
        return this;
    }
<p>
Data about the alarm, in JSON format.
</p>

@param historyData
       Data about the alarm, in JSON format.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-cloudwatch/src/main/java/com/amazonaws/services/cloudwatch/model/AlarmHistoryItem.java