diff --git a/build/dependencies/setupJdk.gradle b/build/dependencies/setupJdk.gradle
index 6b58c0f8534d..9dc71e2f4e7d 100644
--- a/build/dependencies/setupJdk.gradle
+++ b/build/dependencies/setupJdk.gradle
@@ -60,24 +60,23 @@ task setupJdk18(dependsOn: downloadJdk18) {
 def unpackJdk(jdkArchive, outputDir) {
   logger.info("Unpacking $jdkArchive to ${outputDir}")
   file(outputDir).deleteDir()
-  if (!org.gradle.internal.os.OperatingSystem.current().isWindows()) {
-    exec { commandLine 'mkdir', '-p', outputDir }
-    exec { commandLine 'tar', 'xpf', "${jdkArchive.absolutePath}", '--directory', outputDir }
-    def jdkContents = file("${outputDir}/jdk/Contents")
-    if (org.gradle.internal.os.OperatingSystem.current().isMacOsX() && jdkContents.exists()) {
-      copy {
-        from fileTree(jdkContents)
-        into outputDir
-      }
-      jdkContents.deleteDir()
-    }
-  }
-  else {
+  def currentOs = org.gradle.internal.os.OperatingSystem.current()
+  if (currentOs.isWindows()) {
     copy {
       from tarTree(jdkArchive)
       into outputDir
     }
   }
+  else {
+    exec { commandLine 'mkdir', '-p', outputDir }
+    exec { commandLine 'tar', 'xpf', "$jdkArchive.absolutePath", '--directory', outputDir }
+    def jdkContents = file("${outputDir}/jdk/Contents")
+    if (currentOs.isMacOsX() && jdkContents.exists()) {
+      jdkContents.listFiles().each { file ->
+        exec { commandLine 'mv', "$file.absolutePath", outputDir }
+      }
+    }
+  }
 }
 
 static def currentPlatformName() {