From 35e27f05e93d71684bca6b0965bfcde36ae5d0d4 Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Mon, 19 Sep 2016 11:41:02 +0200
Subject: [PATCH] use UrlClassLoader for speedier teamcity test initialization

---
 .../tests/ExternalClasspathClassLoader.java   | 23 +++++++++++--------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/platform/testFramework/bootstrap/src/com/intellij/tests/ExternalClasspathClassLoader.java b/platform/testFramework/bootstrap/src/com/intellij/tests/ExternalClasspathClassLoader.java
index c780281b0862..18599b74967e 100644
--- a/platform/testFramework/bootstrap/src/com/intellij/tests/ExternalClasspathClassLoader.java
+++ b/platform/testFramework/bootstrap/src/com/intellij/tests/ExternalClasspathClassLoader.java
@@ -28,14 +28,7 @@ import java.util.LinkedHashSet;
 /**
  * @author max
  */
-public class ExternalClasspathClassLoader extends URLClassLoader {
-  static {
-    registerAsParallelCapable();
-  }
-
-  private ExternalClasspathClassLoader(URL[] urls) {
-    super(urls, Thread.currentThread().getContextClassLoader());
-  }
+public class ExternalClasspathClassLoader {
 
   private static String[] parseUrls(String classpathFilePath) {
     Collection<String> roots = new LinkedHashSet<>();
@@ -79,7 +72,9 @@ public class ExternalClasspathClassLoader extends URLClassLoader {
     try {
       URL[] urls = parseUrls();
       if (urls != null) {
-        Thread.currentThread().setContextClassLoader(new ExternalClasspathClassLoader(urls));
+        URLClassLoader auxLoader = new URLClassLoader(urls, Thread.currentThread().getContextClassLoader());
+        Thread.currentThread().setContextClassLoader(auxLoader);
+        Thread.currentThread().setContextClassLoader(loadOptimizedLoader(urls, auxLoader));
       }
     }
     catch (Exception e) {
@@ -87,6 +82,16 @@ public class ExternalClasspathClassLoader extends URLClassLoader {
     }
   }
 
+  private static ClassLoader loadOptimizedLoader(Object urls, URLClassLoader auxLoader) throws Exception {
+    Object builder = auxLoader.loadClass("com.intellij.util.lang.UrlClassLoader").getMethod("build").invoke(null);
+    builder.getClass().getMethod("urls", URL[].class).invoke(builder, urls);
+    builder.getClass().getMethod("useCache").invoke(builder);
+    builder.getClass().getMethod("allowLock").invoke(builder);
+    builder.getClass().getMethod("allowBootstrapResources").invoke(builder);
+    builder.getClass().getMethod("parent", ClassLoader.class).invoke(builder, auxLoader.getParent());
+    return (ClassLoader)builder.getClass().getMethod("get").invoke(builder);
+  }
+
   private static URL[] parseUrls() {
     try {
       String[] roots = getRoots();