From 342c97d8ba33512b87d79627c3dbfdf04f9fa42e Mon Sep 17 00:00:00 2001
From: Simone Bordet <simone.bordet@gmail.com>
Date: Thu, 27 Mar 2014 15:37:23 +0100
Subject: [PATCH] 430654 - closing client connections can hang worker threads.

Prettified usage of NonBlockingThread and added Javadocs.
---
 .../org/eclipse/jetty/io/SelectorManager.java | 21 +++++----------
 .../jetty/util/thread/NonBlockingThread.java  | 26 ++++++++++++++++---
 2 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/jetty-io/src/main/java/org/eclipse/jetty/io/SelectorManager.java b/jetty-io/src/main/java/org/eclipse/jetty/io/SelectorManager.java
index c2dbbd83b7a..fd3c6c6b9ee 100644
--- a/jetty-io/src/main/java/org/eclipse/jetty/io/SelectorManager.java
+++ b/jetty-io/src/main/java/org/eclipse/jetty/io/SelectorManager.java
@@ -204,7 +204,7 @@ public abstract class SelectorManager extends AbstractLifeCycle implements Dumpa
             ManagedSelector selector = newSelector(i);
             _selectors[i] = selector;
             selector.start();
-            execute(selector);
+            execute(new NonBlockingThread(selector));
         }
     }
 
@@ -476,21 +476,14 @@ public abstract class SelectorManager extends AbstractLifeCycle implements Dumpa
         public void run()
         {
             _thread = Thread.currentThread();
-            final String name = _thread.getName();
+            String name = _thread.getName();
             try
             {
-                NonBlockingThread.runAsNonBlocking(new Runnable()
-                {
-                    @Override
-                    public void run()
-                    {
-                        _thread.setName(name + "-selector-" + SelectorManager.this.getClass().getSimpleName()+"@"+Integer.toHexString(SelectorManager.this.hashCode())+"/"+_id);
-                        LOG.debug("Starting {} on {}", _thread, this);
-                        while (isRunning())
-                            select();
-                        runChanges();
-                    }
-                });
+                _thread.setName(name + "-selector-" + SelectorManager.this.getClass().getSimpleName()+"@"+Integer.toHexString(SelectorManager.this.hashCode())+"/"+_id);
+                LOG.debug("Starting {} on {}", _thread, this);
+                while (isRunning())
+                    select();
+                runChanges();
             }
             finally
             {
diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/thread/NonBlockingThread.java b/jetty-util/src/main/java/org/eclipse/jetty/util/thread/NonBlockingThread.java
index 64076d31174..4fb75c7fb0c 100644
--- a/jetty-util/src/main/java/org/eclipse/jetty/util/thread/NonBlockingThread.java
+++ b/jetty-util/src/main/java/org/eclipse/jetty/util/thread/NonBlockingThread.java
@@ -18,20 +18,38 @@
 
 package org.eclipse.jetty.util.thread;
 
-public class NonBlockingThread 
+/**
+ * Marker that wraps a Runnable, indicating that it is running in a thread that must not be blocked.
+ * <p />
+ * Client code can use the thread-local {@link #isNonBlockingThread()} to detect whether they are
+ * in the context of a non-blocking thread, and perform different actions if that's the case.
+ */
+public class NonBlockingThread implements Runnable
 {
-    private final static ThreadLocal<Boolean> __nonBlockingThread = new ThreadLocal<>(); 
+    private final static ThreadLocal<Boolean> __nonBlockingThread = new ThreadLocal<>();
+
+    /**
+     * @return whether the current thread is a thread that must not block.
+     */
     public static boolean isNonBlockingThread()
     {
         return Boolean.TRUE.equals(__nonBlockingThread.get());
     }
 
-    public static void runAsNonBlocking(Runnable runnable)
+    private final Runnable delegate;
+
+    public NonBlockingThread(Runnable delegate)
+    {
+        this.delegate = delegate;
+    }
+
+    @Override
+    public void run()
     {
         try
         {
             __nonBlockingThread.set(Boolean.TRUE);
-            runnable.run();
+            delegate.run();
         }
         finally
         {