DOCS : Add some java docs.

Original commit: elastic/x-pack-elasticsearch@394d957364

src/main/java/org/elasticsearch/alerts/AlertAckState.java

@@ -11,7 +11,12 @@ import org.elasticsearch.common.xcontent.XContentBuilder;
 import java.io.IOException;
 
 /**
- * @TODO add jdocs
+ * This class represents the ack (acknowleged state of an alert)
+ *
+ * NOT_ACKABLE : This alert cannot be ACKed
+ * NOT_TRIGGERED : This alert is in the base line state. A positive trigger will cause the alert to move to the NEEDS_ACK state
+ * NEEDS_ACK : This alert is in the fired state and has sent an alert action, subsequent positive triggers will cause more actions to occur
+ * ACKED : This alert has been acknowleged, subsequent positive triggers will not cause actions to occur, a negative trigger will move the alert back into NOT_TRIGGERED state
  */
 public enum AlertAckState implements ToXContent {
     NOT_ACKABLE, ///@TODO perhaps null

src/main/java/org/elasticsearch/alerts/transport/actions/ack/AckAlertResponse.java

@@ -14,6 +14,7 @@ import org.elasticsearch.common.io.stream.StreamOutput;
 import java.io.IOException;
 
 /**
+ * This class contains the ackState of the alert, if the alert was successfully acked this will be ACK
  */
 public class AckAlertResponse extends ActionResponse {
 
@@ -22,14 +23,25 @@ public class AckAlertResponse extends ActionResponse {
     public AckAlertResponse() {
     }
 
+    /**
+     * The Constructor that takes the ack state for the alert
+     * @param alertAckState
+     */
     public AckAlertResponse(@Nullable AlertAckState alertAckState) {
         this.alertAckState = alertAckState;
     }
 
+    /**
+     * @return The ack state for the alert
+     */
     public AlertAckState getAlertAckState() {
         return alertAckState;
     }
 
+    public void setAlertAckState(AlertAckState alertAckState) {
+        this.alertAckState = alertAckState;
+    }
+
     @Override
     public void readFrom(StreamInput in) throws IOException {
         super.readFrom(in);