Use bytes instead of a string for IP address.

Ported from internal.

Author: zhangkun83

grpclb/src/generated/main/java/io/grpc/grpclb/LoadBalancerProto.java

@@ -35,6 +35,7 @@
 import com.google.common.base.Preconditions;
 import com.google.common.base.Supplier;
 import com.google.common.base.Suppliers;
+import com.google.common.base.Throwables;
 
 import io.grpc.Attributes;
 import io.grpc.Channel;
@@ -49,8 +50,10 @@
 import io.grpc.internal.SharedResourceHolder;
 import io.grpc.stub.StreamObserver;
 
+import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
+import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -285,13 +288,17 @@ private class LbResponseObserver implements StreamObserver<LoadBalanceResponse>
         if (server.getDropRequest()) {
           listBuilder.add(null);
         } else {
-          InetSocketAddress address = new InetSocketAddress(
-              server.getIpAddress(), server.getPort());
-          listBuilder.add(address);
-          // TODO(zhangkun83): fill the LB token to the attributes, and insert it to the
-          // application RPCs.
-          if (!newServerMap.containsKey(address)) {
-            newServerMap.put(address, new ResolvedServerInfo(address, Attributes.EMPTY));
+          try {
+            InetSocketAddress address = new InetSocketAddress(
+                InetAddress.getByAddress(server.getIpAddress().toByteArray()), server.getPort());
+            listBuilder.add(address);
+            // TODO(zhangkun83): fill the LB token to the attributes, and insert it to the
+            // application RPCs.
+            if (!newServerMap.containsKey(address)) {
+              newServerMap.put(address, new ResolvedServerInfo(address, Attributes.EMPTY));
+            }
+          } catch (UnknownHostException e) {
+            Throwables.propagate(e);
           }
         }
       }

grpclb/src/generated/main/java/io/grpc/grpclb/Server.java

@@ -89,9 +89,11 @@ message ServerList {
 }
 
 message Server {
-  // A resolved address and port for the server. The IP address string may
+  // A resolved address for the server, serialized in network-byte-order. It may
   // either be an IPv4 or IPv6 address.
-  string ip_address = 1;
+  bytes ip_address = 1;
+
+  // A resolved port number for the server.
   int32 port = 2;
 
   // An opaque token that is passed from the client to the server in metadata.

grpclb/src/generated/main/java/io/grpc/grpclb/ServerOrBuilder.java

@@ -46,6 +46,7 @@
 import static org.mockito.Mockito.withSettings;
 
 import com.google.common.base.Supplier;
+import com.google.protobuf.ByteString;
 
 import io.grpc.Attributes;
 import io.grpc.EquivalentAddressGroup;
@@ -476,7 +477,7 @@ private static LoadBalanceResponse buildLbResponse(List<ResolvedServerInfo> serv
     for (ResolvedServerInfo server : servers) {
       InetSocketAddress addr = (InetSocketAddress) server.getAddress();
       serverListBuilder.addServers(Server.newBuilder()
-          .setIpAddress(addr.getHostString())
+          .setIpAddress(ByteString.copyFrom(addr.getAddress().getAddress()))
           .setPort(addr.getPort())
           .build());
     }