[SPARK-14725][Core] Remove HttpServer class

repl/src/test/scala/org/apache/spark/repl/ExecutorClassLoaderSuite.scala

@@ -57,7 +57,6 @@ class ExecutorClassLoaderSuite
   var tempDir2: File = _
   var url1: String = _
   var urls2: Array[URL] = _
-  var classServer: HttpServer = _
 
   override def beforeAll() {
     super.beforeAll()
@@ -74,9 +73,6 @@ class ExecutorClassLoaderSuite
 
   override def afterAll() {
     try {
-      if (classServer != null) {
-        classServer.stop()
-      }
       Utils.deleteRecursively(tempDir1)
       Utils.deleteRecursively(tempDir2)
       SparkEnv.set(null)
@@ -137,55 +133,6 @@ class ExecutorClassLoaderSuite
     assert(fileReader.readLine().contains("resource"), "File doesn't contain 'resource'")
   }
 
-  test("failing to fetch classes from HTTP server should not leak resources (SPARK-6209)") {
-    // This is a regression test for SPARK-6209, a bug where each failed attempt to load a class
-    // from the driver's class server would leak a HTTP connection, causing the class server's
-    // thread / connection pool to be exhausted.
-    val conf = new SparkConf()
-    val securityManager = new SecurityManager(conf)
-    classServer = new HttpServer(conf, tempDir1, securityManager)
-    classServer.start()
-    // ExecutorClassLoader uses SparkEnv's SecurityManager, so we need to mock this
-    val mockEnv = mock[SparkEnv]
-    when(mockEnv.securityManager).thenReturn(securityManager)
-    SparkEnv.set(mockEnv)
-    // Create an ExecutorClassLoader that's configured to load classes from the HTTP server
-    val parentLoader = new URLClassLoader(Array.empty, null)
-    val classLoader = new ExecutorClassLoader(conf, null, classServer.uri, parentLoader, false)
-    classLoader.httpUrlConnectionTimeoutMillis = 500
-    // Check that this class loader can actually load classes that exist
-    val fakeClass = classLoader.loadClass("ReplFakeClass2").newInstance()
-    val fakeClassVersion = fakeClass.toString
-    assert(fakeClassVersion === "1")
-    // Try to perform a full GC now, since GC during the test might mask resource leaks
-    System.gc()
-    // When the original bug occurs, the test thread becomes blocked in a classloading call
-    // and does not respond to interrupts.  Therefore, use a custom ScalaTest interruptor to
-    // shut down the HTTP server when the test times out
-    val interruptor: Interruptor = new Interruptor {
-      override def apply(thread: Thread): Unit = {
-        classServer.stop()
-        classServer = null
-        thread.interrupt()
-      }
-    }
-    def tryAndFailToLoadABunchOfClasses(): Unit = {
-      // The number of trials here should be much larger than Jetty's thread / connection limit
-      // in order to expose thread or connection leaks
-      for (i <- 1 to 1000) {
-        if (Thread.currentThread().isInterrupted) {
-          throw new InterruptedException()
-        }
-        // Incorporate the iteration number into the class name in order to avoid any response
-        // caching that might be added in the future
-        intercept[ClassNotFoundException] {
-          classLoader.loadClass(s"ReplFakeClassDoesNotExist$i").newInstance()
-        }
-      }
-    }
-    failAfter(10 seconds)(tryAndFailToLoadABunchOfClasses())(interruptor)
-  }
-
   test("fetch classes using Spark's RpcEnv") {
     val env = mock[SparkEnv]
     val rpcEnv = mock[RpcEnv]