7008595: Class loader leak caused by keepAliveTimer thread in KeepAliveCache

Reviewed-by: michaelm

src/share/classes/sun/net/www/http/KeepAliveCache.java

@@ -106,6 +106,9 @@ public class KeepAliveCache
                     keepAliveTimer = new Thread(grp, cache, "Keep-Alive-Timer");
                     keepAliveTimer.setDaemon(true);
                     keepAliveTimer.setPriority(Thread.MAX_PRIORITY - 2);
+                    // Set the context class loader to null in order to avoid
+                    // keeping a strong reference to an application classloader.
+                    keepAliveTimer.setContextClassLoader(null);
                     keepAliveTimer.start();
                     return null;
                 }

src/share/classes/sun/net/www/http/KeepAliveStream.java

@@ -185,6 +185,9 @@ class KeepAliveStream extends MeteredStream implements Hurryable {
                         cleanerThread = new Thread(grp, queue, "Keep-Alive-SocketCleaner");
                         cleanerThread.setDaemon(true);
                         cleanerThread.setPriority(Thread.MAX_PRIORITY - 2);
+                        // Set the context class loader to null in order to avoid
+                        // keeping a strong reference to an application classloader.
+                        cleanerThread.setContextClassLoader(null);
                         cleanerThread.start();
                         return null;
                     }