getServiceSLATrend:

1. Change the parameter name:
Start -> startTimeBucket
End -> endTimeBucket

apm-collector/apm-collector-ui/collector-ui-jetty-provider/src/main/java/org/apache/skywalking/apm/collector/ui/query/ServiceQuery.java

@@ -81,9 +81,9 @@ public class ServiceQuery implements Query {
     }
 
     public SLATrend getServiceSLATrend(int serviceId, Duration duration) throws ParseException {
-        long start = DurationUtils.INSTANCE.exchangeToTimeBucket(duration.getStart());
-        long end = DurationUtils.INSTANCE.exchangeToTimeBucket(duration.getEnd());
-        return getServiceNameService().getServiceSLATrend(serviceId, duration.getStep(), start, end);
+        long startTimeBucket = DurationUtils.INSTANCE.exchangeToTimeBucket(duration.getStart());
+        long endTimeBucket = DurationUtils.INSTANCE.exchangeToTimeBucket(duration.getEnd());
+        return getServiceNameService().getServiceSLATrend(serviceId, duration.getStep(), startTimeBucket, endTimeBucket);
     }
 
     public Topology getServiceTopology(int serviceId, Duration duration) throws ParseException {

apm-collector/apm-collector-ui/collector-ui-jetty-provider/src/main/java/org/apache/skywalking/apm/collector/ui/service/ServiceNameService.java

@@ -87,9 +87,9 @@ public class ServiceNameService {
         return responseTimeTrend;
     }
 
-    public SLATrend getServiceSLATrend(int serviceId, Step step, long start, long end) throws ParseException {
+    public SLATrend getServiceSLATrend(int serviceId, Step step, long startTimeBucket, long endTimeBucket) throws ParseException {
         SLATrend slaTrend = new SLATrend();
-        List<DurationPoint> durationPoints = DurationUtils.INSTANCE.getDurationPoints(step, start, end);
+        List<DurationPoint> durationPoints = DurationUtils.INSTANCE.getDurationPoints(step, startTimeBucket, endTimeBucket);
         slaTrend.setTrendList(serviceMetricUIDAO.getServiceSLATrend(serviceId, step, durationPoints));
         return slaTrend;
     }