use String.contains() to improve the readability

Author: thurka

visualvm/libs.profiler/lib.profiler.charts/src/org/graalvm/visualvm/lib/charts/axis/TimeAxisUtils.java

@@ -228,7 +228,7 @@ private static String createDateMonth(String dateYear) {
     }
 
     private static boolean isPatternChar(String s) {
-        return PATTERN_CHARS.indexOf(s) != -1;
+        return PATTERN_CHARS.contains(s);
     }
 
 }

visualvm/libs.profiler/lib.profiler.common/src/org/graalvm/visualvm/lib/common/integration/IntegrationUtils.java

@@ -230,7 +230,7 @@ public static boolean isFileModifiedForProfiler(File file) {
                 return false;
             }
 
-            if (line.indexOf(MODIFIED_FOR_PROFILER_STRING) != -1) {
+            if (line.contains(MODIFIED_FOR_PROFILER_STRING)) {
                 br.close();
 
                 return true;
@@ -245,7 +245,7 @@ public static boolean isFileModifiedForProfiler(File file) {
                 return false;
             }
 
-            if (line.indexOf(MODIFIED_FOR_PROFILER_STRING) != -1) {
+            if (line.contains(MODIFIED_FOR_PROFILER_STRING)) {
                 br.close();
 
                 return true;

visualvm/libs.profiler/lib.profiler.ui/src/org/graalvm/visualvm/lib/ui/components/JExtendedTable.java

@@ -403,7 +403,7 @@ public void keyPressed(KeyEvent e) {
     }
 
     private boolean matchesFindCriterion(int row) {
-        return getValueAt(row, userFindColumn).toString().toLowerCase().indexOf(internalFindString) != -1;
+        return getValueAt(row, userFindColumn).toString().toLowerCase().contains(internalFindString);
     }
 
     private boolean selectFoundNode(int row) {

visualvm/libs.profiler/lib.profiler.ui/src/org/graalvm/visualvm/lib/ui/components/JTreeTable.java

@@ -1118,7 +1118,7 @@ private boolean matchesFindCriterion(Object node) {
         if (o == null) return false; // #207622, probably caused by updating the table while searching
         String s = o.toString();
         if (s == null) return false; // #207622, likely won't happen but just to be sure
-        return s.toLowerCase().indexOf(internalFindString) != -1;
+        return s.toLowerCase().contains(internalFindString);
     }
 
     private boolean selectFoundNode(CCTNode nodeToSelect, boolean requestFocus) {