Improve dnsjava algorithm

gatling-http/src/main/scala/io/gatling/http/request/builder/RequestExpressionBuilder.scala

@@ -29,12 +29,11 @@ import io.gatling.http.ahc.ChannelPoolPartitioning
 import io.gatling.http.config.HttpProtocol
 import io.gatling.http.cookie.CookieSupport
 import io.gatling.http.referer.RefererHandling
-import io.gatling.http.util.HttpHelper
+import io.gatling.http.util.{ DnsHelper, HttpHelper }
 
 import scala.util.control.NonFatal
 
 import com.typesafe.scalalogging.LazyLogging
-import org.xbill.DNS.Address
 
 object RequestExpressionBuilder {
   val BuildRequestErrorMapper = "Failed to build request: " + _
@@ -71,7 +70,7 @@ abstract class RequestExpressionBuilder(commonAttributes: CommonAttributes, prot
             case Some(address) => address
             case None =>
               try {
-                Address.getByName(name)
+                DnsHelper.getAddressByName(name)
               } catch {
                 case NonFatal(e) =>
                   logger.warn(s"Failed to resolve address of name $name")

gatling-http/src/main/scala/io/gatling/http/util/DnsHelper.scala

@@ -0,0 +1,60 @@
+/**
+ * Copyright 2011-2015 eBusiness Information, Groupe Excilys (www.ebusinessinformation.fr)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.gatling.http.util
+
+import java.net.{ UnknownHostException, InetAddress }
+
+import org.xbill.DNS.Address._
+import org.xbill.DNS._
+
+object DnsHelper {
+
+  @throws(classOf[UnknownHostException])
+  def getAddressByName(name: String): InetAddress =
+    toByteArray(name, IPv4) match {
+      case null =>
+        toByteArray(name, IPv6) match {
+          case null =>
+            val address = lookupHostNameAddress(name)
+            InetAddress.getByAddress(name, address.getAddress)
+
+          case ipV6Bytes => InetAddress.getByAddress(name, ipV6Bytes)
+        }
+
+      case ipV4Bytes => InetAddress.getByAddress(name, ipV4Bytes)
+    }
+
+  @throws(classOf[UnknownHostException])
+  private def lookupHostNameAddress(name: String): InetAddress =
+    try {
+      val lookup: Lookup = new Lookup(name, Type.A)
+      lookup.run match {
+        case null =>
+          if (lookup.getResult == Lookup.TYPE_NOT_FOUND) {
+            new Lookup(name, Type.AAAA).run match {
+              case null => throw new UnknownHostException("unknown host")
+              case aaaa => aaaa(0).asInstanceOf[AAAARecord].getAddress
+            }
+          } else {
+            throw new UnknownHostException("unknown host")
+          }
+
+        case a => a(0).asInstanceOf[ARecord].getAddress
+      }
+    } catch {
+      case e: TextParseException => throw new UnknownHostException("invalid name")
+    }
+}