From c4304fe07d365d77e4e2bf83b5fd44a4f494139b Mon Sep 17 00:00:00 2001
From: Miron Cuperman <miron+code@google.com>
Date: Fri, 3 Aug 2012 16:49:45 -0700
Subject: [PATCH] Bring back PeerGroupThreadFactory

---
 .../com/google/bitcoin/core/PeerGroup.java    | 31 +++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/core/src/main/java/com/google/bitcoin/core/PeerGroup.java b/core/src/main/java/com/google/bitcoin/core/PeerGroup.java
index 0d96015f6..b0c38331d 100644
--- a/core/src/main/java/com/google/bitcoin/core/PeerGroup.java
+++ b/core/src/main/java/com/google/bitcoin/core/PeerGroup.java
@@ -37,6 +37,7 @@ import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.util.*;
 import java.util.concurrent.*;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -142,8 +143,8 @@ public class PeerGroup {
             int connectionDelayMillis) {
         this(params, chain, connectionDelayMillis, new ClientBootstrap(
                 new NioClientSocketChannelFactory(
-                        Executors.newCachedThreadPool(), 
-                        Executors.newCachedThreadPool())));
+                        Executors.newCachedThreadPool(new PeerGroupThreadFactory()), 
+                        Executors.newCachedThreadPool(new PeerGroupThreadFactory()))));
         bootstrap.setPipelineFactory(makePipelineFactory(params, chain));
     }
 
@@ -908,4 +909,30 @@ public class PeerGroup {
         }, MoreExecutors.sameThreadExecutor());
         return future;
     }
+
+    static class PeerGroupThreadFactory implements ThreadFactory {
+        static final AtomicInteger poolNumber = new AtomicInteger(1);
+        final ThreadGroup group;
+        final AtomicInteger threadNumber = new AtomicInteger(1);
+        final String namePrefix;
+
+        PeerGroupThreadFactory() {
+            group = Thread.currentThread().getThreadGroup();
+            namePrefix = "PeerGroup-" +
+            poolNumber.getAndIncrement() +
+            "-thread-";
+        }
+
+        public Thread newThread(Runnable r) {
+            Thread t = new Thread(group, r,
+                    namePrefix + threadNumber.getAndIncrement(),
+                    0);
+            // Lower the priority of the peer threads. This is to avoid competing with UI threads created by the API
+            // user when doing lots of work, like downloading the block chain. We select a priority level one lower
+            // than the parent thread, or the minimum.
+            t.setPriority(Math.max(Thread.MIN_PRIORITY, Thread.currentThread().getPriority() - 1));
+            t.setDaemon(true);
+            return t;
+        }
+    }
 }