Add returning modified status of `updateProperty` method in SentinelProperty

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-core/src/main/java/com/alibaba/csp/sentinel/property/DynamicSentinelProperty.java

@@ -46,9 +46,9 @@ public class DynamicSentinelProperty<T> implements SentinelProperty<T> {
     }
 
     @Override
-    public void updateValue(T newValue) {
+    public boolean updateValue(T newValue) {
         if (isEqual(value, newValue)) {
-            return;
+            return false;
         }
         RecordLog.info("[DynamicSentinelProperty] Config will be updated to: " + newValue);
 
@@ -56,7 +56,7 @@ public class DynamicSentinelProperty<T> implements SentinelProperty<T> {
         for (PropertyListener<T> listener : listeners) {
             listener.configUpdate(newValue);
         }
-
+        return true;
     }
 
     private boolean isEqual(T oldValue, T newValue) {

sentinel-core/src/main/java/com/alibaba/csp/sentinel/property/NoOpSentinelProperty.java

@@ -21,6 +21,7 @@ package com.alibaba.csp.sentinel.property;
  * @author leyou
  */
 public final class NoOpSentinelProperty implements SentinelProperty<Object> {
+
     @Override
     public void addListener(PropertyListener<Object> listener) { }
 
@@ -28,5 +29,7 @@ public final class NoOpSentinelProperty implements SentinelProperty<Object> {
     public void removeListener(PropertyListener<Object> listener) { }
 
     @Override
-    public void updateValue(Object newValue) { }
+    public boolean updateValue(Object newValue) {
+        return true;
+    }
 }

sentinel-core/src/main/java/com/alibaba/csp/sentinel/property/SentinelProperty.java

@@ -56,6 +56,7 @@ public interface SentinelProperty<T> {
      * added on this only when new {@code newValue} is not Equals to the old value.
      *
      * @param newValue the new value.
+     * @return true if the value in property has been updated, otherwise false
      */
-    void updateValue(T newValue);
+    boolean updateValue(T newValue);
 }