fix some of findbugs issues

Change-Id: I20aa54af16f3a1e3323d735fe53cc26c03d5e52e
diff --git a/utils/misc/src/main/java/org/onlab/packet/IPv4.java b/utils/misc/src/main/java/org/onlab/packet/IPv4.java
index 4b9fd66..634ceff 100644
--- a/utils/misc/src/main/java/org/onlab/packet/IPv4.java
+++ b/utils/misc/src/main/java/org/onlab/packet/IPv4.java
@@ -438,7 +438,7 @@
 
         int result = 0;
         for (int i = 0; i < 4; ++i) {
-            result |= Integer.valueOf(octets[i]) << (3 - i) * 8;
+            result |= Integer.parseInt(octets[i]) << (3 - i) * 8;
         }
         return result;
     }
@@ -471,7 +471,7 @@
         int result = 0;
         for (int i = 0; i < 4; ++i) {
             result = ipAddress >> (3 - i) * 8 & 0xff;
-        sb.append(Integer.valueOf(result).toString());
+        sb.append(result);
         if (i != 3) {
             sb.append(".");
         }