allow thread pool naming

src/main/java/org/cobbzilla/util/daemon/DaemonThreadFactory.java

@@ -1,28 +1,45 @@
 package org.cobbzilla.util.daemon;
 
+import lombok.NoArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicInteger;
 
-@Slf4j
+import static java.util.concurrent.Executors.newFixedThreadPool;
+
+@Slf4j @NoArgsConstructor
 public class DaemonThreadFactory implements ThreadFactory {
 
     public static final DaemonThreadFactory instance = new DaemonThreadFactory();
 
+    public DaemonThreadFactory (String name) { this.name = name+"-"; }
+
+    private String name = "DaemonThread-";
+    private final AtomicInteger counter = new AtomicInteger();
+
     @Override public Thread newThread(Runnable r) {
         final Thread t = new Thread(r);
         t.setDaemon(true);
+        t.setName(name+counter.incrementAndGet());
         return t;
     }
 
+    public static ExecutorService fixedPool (int count, String name) {
+        if (count <= 0) {
+            log.warn("fixedPool: invalid count ("+count+"), using single thread");
+            count = 1;
+        }
+        return newFixedThreadPool(count, new DaemonThreadFactory(name));
+    }
+
     public static ExecutorService fixedPool (int count) {
         if (count <= 0) {
             log.warn("fixedPool: invalid count ("+count+"), using single thread");
             count = 1;
         }
-        return Executors.newFixedThreadPool(count, instance);
+        return newFixedThreadPool(count, instance);
     }
 
 }

src/main/java/org/cobbzilla/util/handlebars/HandlebarsUtil.java

@@ -680,7 +680,7 @@ public class HandlebarsUtil extends AbstractTemplateLoader {
                 : null;
     }
 
-    private static final ExecutorService contextSender = fixedPool(10);
+    private static final ExecutorService contextSender = fixedPool(10, "HandlebarsUtil.contextSender");
 
     public static void sendContext(String recipient, String subject, String message, String contentType) {
         contextSender.submit(() -> {

src/main/java/org/cobbzilla/util/io/FilesystemWalker.java

@@ -45,7 +45,7 @@ public class FilesystemWalker {
     public FilesystemWalker withVisitor (FilesystemVisitor visitor) { visitors.add(visitor); return this; }
     public FilesystemWalker withTimeoutDuration (String duration) { setTimeout(parseDuration(duration)); return this; }
 
-    @Getter(lazy=true) private final ExecutorService pool = fixedPool(getThreads());
+    @Getter(lazy=true) private final ExecutorService pool = fixedPool(getThreads(), "FilesystemWalker.pool");
     @Getter(lazy=true) private final List<Future<?>> futures = new ArrayList<>(getSize());
 
     public AwaitResult walk() {