diff --git a/webmagic-core/src/main/java/us/codecraft/webmagic/utils/NumberUtils.java b/webmagic-core/src/main/java/us/codecraft/webmagic/utils/NumberUtils.java
index 55e18510..fbeb8ed3 100644
--- a/webmagic-core/src/main/java/us/codecraft/webmagic/utils/NumberUtils.java
+++ b/webmagic-core/src/main/java/us/codecraft/webmagic/utils/NumberUtils.java
@@ -6,12 +6,6 @@ package us.codecraft.webmagic.utils;
 public abstract class NumberUtils {
 
     public static int compareLong(long o1, long o2) {
-        if (o1 < o2) {
-            return -1;
-        } else if (o1 == o2) {
-            return 0;
-        } else {
-            return 1;
-        }
+    	return Long.compare(o1, o2);
     }
 }
diff --git a/webmagic-core/src/main/java/us/codecraft/webmagic/utils/WMCollections.java b/webmagic-core/src/main/java/us/codecraft/webmagic/utils/WMCollections.java
index 23e1644c..a2ca5afd 100644
--- a/webmagic-core/src/main/java/us/codecraft/webmagic/utils/WMCollections.java
+++ b/webmagic-core/src/main/java/us/codecraft/webmagic/utils/WMCollections.java
@@ -21,10 +21,10 @@ public class WMCollections {
     }
 
     public static <T> List<T> newArrayList(T... t){
-        List<T> set = new ArrayList<T>(t.length);
+        List<T> list = new ArrayList<T>(t.length);
         for (T t1 : t) {
-            set.add(t1);
+            list.add(t1);
         }
-        return set;
+        return list;
     }
 }