diff --git a/library/src/main/java/com/cundong/recyclerview/RecyclerViewUtils.java b/library/src/main/java/com/cundong/recyclerview/RecyclerViewUtils.java
index 234d02d..1732853 100644
--- a/library/src/main/java/com/cundong/recyclerview/RecyclerViewUtils.java
+++ b/library/src/main/java/com/cundong/recyclerview/RecyclerViewUtils.java
@@ -10,6 +10,9 @@
  */
 public class RecyclerViewUtils {
 
+    private  RecyclerViewUtils() throws InstantiationException{
+        throw new InstantiationException("This class is not meant to be instantiated");
+    }
     /**
      * 设置HeaderView
      *
diff --git a/sample/src/main/java/com/cundong/recyclerview/sample/utils/NetworkUtils.java b/sample/src/main/java/com/cundong/recyclerview/sample/utils/NetworkUtils.java
index 8faf90c..5e7a268 100644
--- a/sample/src/main/java/com/cundong/recyclerview/sample/utils/NetworkUtils.java
+++ b/sample/src/main/java/com/cundong/recyclerview/sample/utils/NetworkUtils.java
@@ -12,6 +12,9 @@
  */
 public class NetworkUtils {
 
+    private NetworkUtils() throws InstantiationException{
+        throw new InstantiationException("This class is not meant to instantiated");
+    }
     /**
      * 判断是不是wifi网络状态
      *
diff --git a/sample/src/main/java/com/cundong/recyclerview/sample/utils/RecyclerViewStateUtils.java b/sample/src/main/java/com/cundong/recyclerview/sample/utils/RecyclerViewStateUtils.java
index a14cb79..d927b29 100644
--- a/sample/src/main/java/com/cundong/recyclerview/sample/utils/RecyclerViewStateUtils.java
+++ b/sample/src/main/java/com/cundong/recyclerview/sample/utils/RecyclerViewStateUtils.java
@@ -14,8 +14,11 @@
  *
  * RecyclerView一共有几种State：Normal/Loading/Error/TheEnd
  */
-public class RecyclerViewStateUtils {
+public final  class RecyclerViewStateUtils {
 
+    private  RecyclerViewStateUtils() throws InstantiationException{
+        throw new InstantiationException("This class is not meant to be instantiated");
+    }
     /**
      * 设置headerAndFooterAdapter的FooterView State
      *