Make sure findLoadedClass is called, also allow for serialization of …

…platform blocking actions
gruetter · Jan 13, 2014 · 9212781 · 9212781
1 parent 72425f3
commit 9212781
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Showing 3 changed files with 31 additions and 23 deletions.
diff --git a/src/dist/scripts/vertx b/src/dist/scripts/vertx
@@ -8,6 +8,8 @@
 
 # Add default JVM options here. You can also use JAVA_OPTS and VERTX_OPTS to pass JVM options to this script.
 
+# VERTX_OPTS="-Dvertx.serialiseBlockingActions=true"
+
 # If you're deploying and undeploying a lot of verticles with dynamic languages it's recommended to enable GC'ing
 # of generated classes and prevent OOM due to a lot of gc
 # JVM_OPTS="-XX:+CMSClassUnloadingEnabled -XX:-UseGCOverheadLimit"

diff --git a/vertx-platform/src/main/java/org/vertx/java/platform/impl/DefaultPlatformManager.java b/vertx-platform/src/main/java/org/vertx/java/platform/impl/DefaultPlatformManager.java
@@ -46,6 +46,7 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.Executor;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipInputStream;
 import java.util.zip.ZipOutputStream;
@@ -73,6 +74,7 @@ public class DefaultPlatformManager implements PlatformManagerInternal, ModuleRe
   private static final String FILE_SEP = System.getProperty("file.separator");
   private static final String MODULE_NAME_SYS_PROP = System.getProperty("vertx.modulename");
   private static final String CLASSPATH_FILE = "vertx_classpath.txt";
+  private static final String SERIALISE_BLOCKING_PROP_NAME = "vertx.serialiseBlockingActions";
 
   private final VertxInternal vertx;
   // deployment name --> deployment
@@ -94,6 +96,7 @@ public class DefaultPlatformManager implements PlatformManagerInternal, ModuleRe
   protected HAManager haManager;
   private boolean stopped;
   private final Queue<String> tempDeployments = new ConcurrentLinkedQueue<>();
+  private Executor backgroundExec;
 
   protected DefaultPlatformManager() {
     this(new DefaultVertx());
@@ -118,6 +121,12 @@ private DefaultPlatformManager(DefaultVertx vertx) {
     this.vertx = new WrappedVertx(vertx);
     this.clusterManager = vertx.clusterManager();
 
+    if (System.getProperty(SERIALISE_BLOCKING_PROP_NAME, "false").equalsIgnoreCase("true")) {
+      this.backgroundExec = new OrderedExecutorFactory(vertx.getBackgroundPool()).getExecutor();
+    } else {
+      this.backgroundExec = vertx.getBackgroundPool();
+    }
+
     String modDir = System.getProperty(MODS_DIR_PROP_NAME);
     if (modDir != null && !modDir.trim().equals("")) {
       modRoot = new File(modDir);
@@ -426,7 +435,7 @@ public void run() {
 
   private <T> void runInBackground(final Runnable runnable, final Handler<AsyncResult<T>> doneHandler) {
     final DefaultContext context = vertx.getOrCreateContext();
-    vertx.getBackgroundPool().execute(new Runnable() {
+    backgroundExec.execute(new Runnable() {
       public void run() {
         try {
           vertx.setContext(context);

diff --git a/vertx-platform/src/main/java/org/vertx/java/platform/impl/ModuleClassLoader.java b/vertx-platform/src/main/java/org/vertx/java/platform/impl/ModuleClassLoader.java
@@ -58,10 +58,6 @@ public class ModuleClassLoader extends URLClassLoader {
   private final boolean loadFromModuleFirst;
   private Set<ModuleClassLoader> modGraph;
 
-  // We use a single static object as a lock to prevent classes from being loaded from any modules concurrently
-  // Otherwise we can get deadlock when classes are loaded from similar sets of modules in different order
-  private static final Object lock = new Object();
-
   public ModuleClassLoader(String modID, ClassLoader platformClassLoader, URL[] classpath,
                            boolean loadFromModuleFirst) {
     super(classpath);
@@ -90,26 +86,27 @@ public void close() {
   @Override
   protected Class<?> loadClass(String name, boolean resolve)
       throws ClassNotFoundException {
-    synchronized (lock) {
-      Class<?> c;
-      if (loadFromModuleFirst) {
-        try {
-          c = loadFromModule(name);
-        } catch (ClassNotFoundException e) {
-          c = platformClassLoader.loadClass(name);
-        }
-      } else {
-        try {
-          c = platformClassLoader.loadClass(name);
-        } catch (ClassNotFoundException e) {
-          c = loadFromModule(name);
-        }
+    Class<?> c = findLoadedClass(name);
+    if (c != null) {
+      return c;
+    }
+    if (loadFromModuleFirst) {
+      try {
+        c = loadFromModule(name);
+      } catch (ClassNotFoundException e) {
+        c = platformClassLoader.loadClass(name);
       }
-      if (resolve) {
-        resolveClass(c);
+    } else {
+      try {
+        c = platformClassLoader.loadClass(name);
+      } catch (ClassNotFoundException e) {
+        c = loadFromModule(name);
       }
-      return c;
     }
+    if (resolve) {
+      resolveClass(c);
+    }
+    return c;
   }
 
   private Class<?> loadFromModule(String name) throws ClassNotFoundException {
@@ -127,7 +124,7 @@ private Class<?> loadFromModule(String name) throws ClassNotFoundException {
     return c;
   }
 
-  protected Class<?> doLoadClass(String name) {
+  protected synchronized Class<?> doLoadClass(String name) {
     Class<?> c = findLoadedClass(name);
     if (c == null) {
       try {