diff --git a/core/src/main/resources/org/apache/spark/ui/static/structured-streaming-page.js b/core/src/main/resources/org/apache/spark/ui/static/structured-streaming-page.js
index 61d0003e37c8c..e0e895c6da4db 100644
--- a/core/src/main/resources/org/apache/spark/ui/static/structured-streaming-page.js
+++ b/core/src/main/resources/org/apache/spark/ui/static/structured-streaming-page.js
@@ -42,9 +42,7 @@ function drawAreaStack(id, labels, values) {
     .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
 
   var data = values.flatMap(function(d) {
-    return Object.keys(d).filter(function(key) {
-      return key !== 'x';
-    }).map(function(key) {
+    return Object.keys(d).filter(k => k !== "x").map(function(key) {
       return {x: d.x, label: key, duration: +d[key]};
     });
   });
diff --git a/ui-test/tests/structured-streaming-page.test.js b/ui-test/tests/structured-streaming-page.test.js
index bba7064ad1ca5..5cbd16921fbdc 100644
--- a/ui-test/tests/structured-streaming-page.test.js
+++ b/ui-test/tests/structured-streaming-page.test.js
@@ -76,10 +76,10 @@ test('drawAreaStack', function () {
 
   expect($('#duration-area-stack-parent').attr("style")).toBe('padding: 8px 0px 8px 8px; border-right: 0px solid white;');
   expect($('#duration-area-stack').find('svg').length).toBe(1);
-  var xAxis = $('[class="x axis"] text');
-  expect(xAxis.length).toBe(2);
 
   // test x axis
+  var xAxis = $('[class="x axis"] text');
+  expect(xAxis.length).toBe(2);
   xAxis.each((index, e) => {
     var xAixsText = "";
     if (index === 0) {
@@ -93,7 +93,6 @@ test('drawAreaStack', function () {
   // test y axis
   var yAxis = $('[class="y axis"] text');
   expect(yAxis.length).toBe(7);
-
   yAxis.each((index, e) => {
     if (index < yAxis.length - 1) {
       expect(e.innerHTML).toBe(5000 * index + "")