diff --git a/src/META-INF/application-template.xml b/src/META-INF/application-template.xml
index bf763a86e..62e1ed188 100644
--- a/src/META-INF/application-template.xml
+++ b/src/META-INF/application-template.xml
@@ -175,6 +175,7 @@
             <!-- 
                当Server为HTTP协议时，ResourceServlet才有效. 默认存在一个有默认属性的resource-servlet节点
                webroot: web资源的根目录, 默认取server节点中的root值
+               servlet: 静态资源HttpServlet的实现，默认使用HttpResourceServlet
                index : 启始页，默认值：index.html
             -->
             <resource-servlet webroot="root" index="index.html">
diff --git a/src/org/redkale/net/http/HttpPrepareServlet.java b/src/org/redkale/net/http/HttpPrepareServlet.java
index cd2debf41..99ff76859 100644
--- a/src/org/redkale/net/http/HttpPrepareServlet.java
+++ b/src/org/redkale/net/http/HttpPrepareServlet.java
@@ -23,13 +23,15 @@ import org.redkale.watch.*;
  *
  * @author zhangjx
  */
-public final class HttpPrepareServlet extends PrepareServlet<String, HttpContext, HttpRequest, HttpResponse, HttpServlet> {
+public class HttpPrepareServlet extends PrepareServlet<String, HttpContext, HttpRequest, HttpResponse, HttpServlet> {
 
-    private SimpleEntry<Predicate<String>, HttpServlet>[] regArray = new SimpleEntry[0];
+    protected final Logger logger = Logger.getLogger(this.getClass().getSimpleName());
 
-    private HttpServlet resourceHttpServlet = new HttpResourceServlet();
+    protected SimpleEntry<Predicate<String>, HttpServlet>[] regArray = new SimpleEntry[0];
 
-    private final Map<String, Class> allMapStrings = new HashMap<>();
+    protected HttpServlet resourceHttpServlet = new HttpResourceServlet();
+
+    protected final Map<String, Class> allMapStrings = new HashMap<>();
 
     @Override
     public void init(HttpContext context, AnyValue config) {
@@ -47,10 +49,16 @@ public final class HttpPrepareServlet extends PrepareServlet<String, HttpContext
                 watch.inject(s);
             });
         }
+        AnyValue resConfig = null;
         if (config != null) {
             AnyValue ssConfig = config.getAnyValue("servlets");
-            AnyValue resConfig = null;
             if (ssConfig != null) {
+                String resServlet = config.getValue("servlet", HttpResourceServlet.class.getName());
+                try {
+                    this.resourceHttpServlet = (HttpServlet) Class.forName(resServlet).newInstance();
+                } catch (Exception e) {
+                    logger.log(Level.WARNING, "init HttpResourceSerlvet(" + resServlet + ") error", e);
+                }
                 resConfig = ssConfig.getAnyValue("resource-servlet");
                 if ((resConfig instanceof DefaultAnyValue) && resConfig.getValue("webroot") == null) {
                     ((DefaultAnyValue) resConfig).addValue("webroot", config.getValue("root"));
@@ -70,8 +78,9 @@ public final class HttpPrepareServlet extends PrepareServlet<String, HttpContext
                 }
                 resConfig = dresConfig;
             }
-            this.resourceHttpServlet.init(context, resConfig);
         }
+        if (this.resourceHttpServlet == null) this.resourceHttpServlet = new HttpResourceServlet();
+        this.resourceHttpServlet.init(context, resConfig);
     }
 
     @Override
diff --git a/src/org/redkale/net/http/HttpResourceServlet.java b/src/org/redkale/net/http/HttpResourceServlet.java
index 067515edf..df0713c5d 100644
--- a/src/org/redkale/net/http/HttpResourceServlet.java
+++ b/src/org/redkale/net/http/HttpResourceServlet.java
@@ -27,7 +27,7 @@ import org.redkale.util.AnyValue;
  */
 public final class HttpResourceServlet extends HttpServlet {
 
-    private static final Logger logger = Logger.getLogger(HttpResourceServlet.class.getSimpleName());
+    protected static final Logger logger = Logger.getLogger(HttpResourceServlet.class.getSimpleName());
 
     protected class WatchThread extends Thread {
 
@@ -63,7 +63,12 @@ public final class HttpResourceServlet extends HttpServlet {
                             } else if (event.kind() == ENTRY_MODIFY) {
                                 FileEntry en = files.get(uri);
                                 if (en != null) {
-                                    Thread.sleep(5000L);  //等待update file完毕
+                                    long d;  //等待update file完毕
+                                    for (;;) {
+                                        d = en.file.lastModified();
+                                        Thread.sleep(2000L);
+                                        if (d == en.file.lastModified()) break;
+                                    }
                                     en.update();
                                 }
                             }
@@ -81,16 +86,16 @@ public final class HttpResourceServlet extends HttpServlet {
     protected final boolean finest = logger.isLoggable(Level.FINEST);
 
     protected final LongAdder cachedLength = new LongAdder();
-    
+
     //缓存总大小, 默认0
     protected long cachelimit = 0 * 1024 * 1024L;
 
     //最大可缓存的文件大小，  大于该值的文件将不被缓存
     protected long cachelengthmax = 1 * 1024 * 1024;
-    
+
     //是否监控缓存文件的变化， 默认不监控
     protected boolean watch = false;
-    
+
     protected File root = new File("./root/");
 
     protected String indexHtml = "index.html";
@@ -162,7 +167,7 @@ public final class HttpResourceServlet extends HttpServlet {
         }
     }
 
-    private static long parseLenth(String value, long defValue) {
+    protected static long parseLenth(String value, long defValue) {
         if (value == null) return defValue;
         value = value.toUpperCase().replace("B", "");
         if (value.endsWith("G")) return Long.decode(value.replace("G", "")) * 1024 * 1024 * 1024;
@@ -204,7 +209,7 @@ public final class HttpResourceServlet extends HttpServlet {
         }
     }
 
-    private FileEntry createFileEntry(String uri) {
+    protected FileEntry createFileEntry(String uri) {
         File rfile = new File(root, uri);
         File file = rfile;
         if (file.isDirectory()) file = new File(rfile, this.indexHtml);
@@ -221,9 +226,9 @@ public final class HttpResourceServlet extends HttpServlet {
         return en;
     }
 
-    private static final class FileEntry {
+    protected static class FileEntry {
 
-        final File file;
+        protected final File file;
 
         private final HttpResourceServlet servlet;
 
diff --git a/src/org/redkale/source/JDBCPoolSource.java b/src/org/redkale/source/JDBCPoolSource.java
index ef2978fe1..4fc322322 100644
--- a/src/org/redkale/source/JDBCPoolSource.java
+++ b/src/org/redkale/source/JDBCPoolSource.java
@@ -129,7 +129,12 @@ public class JDBCPoolSource {
                     try {
                         while (!this.isInterrupted()) {
                             final WatchKey key = watcher.take();
-                            Thread.sleep(3000); //防止文件正在更新过程中去读取
+                            long d;   //防止文件正在更新过程中去读取
+                            for (;;) {
+                                d = f.lastModified();
+                                Thread.sleep(2000L);
+                                if (d == f.lastModified()) break;
+                            }
                             final Map<String, Properties> m = loadProperties(new FileInputStream(file));
                             key.pollEvents().stream().forEach((event) -> {
                                 if (event.kind() != ENTRY_MODIFY) return;