fix some of findbugs issues

Change-Id: I20aa54af16f3a1e3323d735fe53cc26c03d5e52e

@@ -399,7 +399,7 @@ public class GossipHostStore
     }
 
     // Auxiliary extension to allow location to mutate.
-    private class StoredHost extends DefaultHost {
+    private static final class StoredHost extends DefaultHost {
         private Timestamped<HostLocation> location;
 
         /**

@@ -269,7 +269,7 @@ public class SimpleHostStore
     }
 
     // Auxiliary extension to allow location to mutate.
-    private class StoredHost extends DefaultHost {
+    private static final class StoredHost extends DefaultHost {
         private HostLocation location;
 
         /**

@@ -32,7 +32,7 @@ public final class ChassisId {
      * @param value the value to use.
      */
     public ChassisId(String value) {
-        this.value = Long.valueOf(value, 16);
+        this.value = Long.parseLong(value, 16);
     }
 
     /**

@@ -379,7 +379,7 @@ public class DHCP extends BasePacket {
         // 300
         int optionsLength = 0;
         for (final DHCPOption option : this.options) {
-            if (option.getCode() == 0 || option.getCode() == 255) {
+            if (option.getCode() == 0 || option.getCode() == ((byte) 255)) {
                 optionsLength += 1;
             } else {
                 optionsLength += 2 + (0xff & option.getLength());

@@ -438,7 +438,7 @@ public class IPv4 extends BasePacket {
 
         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 @@ public class IPv4 extends BasePacket {
         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(".");
         }

@@ -14,7 +14,7 @@ public final class HexString {
      */
     public static String toHexString(final byte[] bytes) {
         int i;
-        StringBuilder ret = new StringBuilder();
+        StringBuilder ret = new StringBuilder(bytes.length * 3 - 1);
         String tmp;
         for (i = 0; i < bytes.length; i++) {
             if (i > 0) {
@@ -31,22 +31,22 @@ public final class HexString {
 
     public static String toHexString(final long val, final int padTo) {
         char[] arr = Long.toHexString(val).toCharArray();
-        String ret = "";
+        StringBuilder ret = new StringBuilder(padTo * 3 - 1);
         // prepend the right number of leading zeros
         int i = 0;
         for (; i < (padTo * 2 - arr.length); i++) {
-            ret += "0";
+            ret.append('0');
             if ((i % 2) != 0) {
-                ret += ":";
+                ret.append(':');
             }
         }
         for (int j = 0; j < arr.length; j++) {
-            ret += arr[j];
+            ret.append(arr[j]);
             if ((((i + j) % 2) != 0) && (j < (arr.length - 1))) {
-                ret += ":";
+                ret.append(':');
             }
         }
-        return ret;
+        return ret.toString();
     }
 
     public static String toHexString(final long val) {

@@ -163,6 +163,7 @@ public class NettyMessagingService implements MessagingService {
         handlers.putIfAbsent(type, handler);
     }
 
+    @Override
     public void unregisterHandler(String type) {
         handlers.remove(type);
     }
@@ -242,7 +243,7 @@ public class NettyMessagingService implements MessagingService {
         }
     }
 
-    private class WriteTask implements Runnable {
+    private static class WriteTask implements Runnable {
 
         private final InternalMessage message;
         private final Channel channel;