diff --git a/webmagic-core/src/main/java/us/codecraft/webmagic/Site.java b/webmagic-core/src/main/java/us/codecraft/webmagic/Site.java
index 6a35178..4c7b992 100644
--- a/webmagic-core/src/main/java/us/codecraft/webmagic/Site.java
+++ b/webmagic-core/src/main/java/us/codecraft/webmagic/Site.java
@@ -96,11 +96,6 @@ public class Site {
      * @return get domain
      */
     public String getDomain() {
-        if (domain == null) {
-            if (startUrls.size() > 0) {
-                domain = UrlUtils.getDomain(startUrls.get(0));
-            }
-        }
         return domain;
     }
 
@@ -176,6 +171,11 @@ public class Site {
      */
     public Site addStartUrl(String startUrl) {
         this.startUrls.add(startUrl);
+        if (domain == null) {
+            if (startUrls.size() > 0) {
+                domain = UrlUtils.getDomain(startUrls.get(0));
+            }
+        }
         return this;
     }
 
diff --git a/webmagic-extension/src/main/java/us/codecraft/webmagic/example/OschinaBlog.java b/webmagic-extension/src/main/java/us/codecraft/webmagic/example/OschinaBlog.java
new file mode 100644
index 0000000..703d6a4
--- /dev/null
+++ b/webmagic-extension/src/main/java/us/codecraft/webmagic/example/OschinaBlog.java
@@ -0,0 +1,59 @@
+package us.codecraft.webmagic.example;
+
+import us.codecraft.webmagic.Page;
+import us.codecraft.webmagic.Site;
+import us.codecraft.webmagic.model.AfterExtractor;
+import us.codecraft.webmagic.model.OOSpider;
+import us.codecraft.webmagic.model.annotation.ExtractBy;
+import us.codecraft.webmagic.model.annotation.Formatter;
+import us.codecraft.webmagic.model.annotation.TargetUrl;
+import us.codecraft.webmagic.pipeline.JsonFilePageModelPipeline;
+
+import java.util.List;
+
+/**
+ * @author code4crafter@gmail.com <br>
+ */
+@TargetUrl("http://my.oschina.net/flashsword/blog/\\d+")
+public class OschinaBlog implements AfterExtractor{
+
+    @ExtractBy("//title/text()")
+    private String title;
+
+    @ExtractBy(value = "div.BlogContent",type = ExtractBy.Type.Css)
+    private String content;
+
+    @ExtractBy(value = "//div[@class='BlogTags']/a/text()", multi = true)
+    private List<String> tags;
+
+    @Formatter("YYYY-MM-dd HH:mm")
+    @ExtractBy("//div[@class='BlogStat']/regex('\\d+-\\d+-\\d+\\s+\\d+:\\d+')")
+    private String date;
+
+    public static void main(String[] args) {
+        OOSpider.create(Site.me().addStartUrl("http://my.oschina.net/flashsword/blog")
+                ,new JsonFilePageModelPipeline("/data/webmagic/"), OschinaBlog.class).run();
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public List<String> getTags() {
+        return tags;
+    }
+
+//    public Date getDate() {
+//        return date;
+//    }
+
+    @Override
+    public void afterProcess(Page page) {
+        System.out.println(date);
+        System.out.println(title);
+    }
+}
diff --git a/webmagic-samples/src/main/java/us/codecraft/webmagic/model/samples/OschinaBlog.java b/webmagic-samples/src/main/java/us/codecraft/webmagic/model/samples/OschinaBlog.java
index 8e6602c..a7f51ad 100644
--- a/webmagic-samples/src/main/java/us/codecraft/webmagic/model/samples/OschinaBlog.java
+++ b/webmagic-samples/src/main/java/us/codecraft/webmagic/model/samples/OschinaBlog.java
@@ -6,7 +6,6 @@ import us.codecraft.webmagic.model.annotation.ExtractBy;
 import us.codecraft.webmagic.model.annotation.TargetUrl;
 import us.codecraft.webmagic.pipeline.JsonFilePageModelPipeline;
 
-import java.util.Date;
 import java.util.List;
 
 /**
@@ -24,9 +23,6 @@ public class OschinaBlog{
     @ExtractBy(value = "//div[@class='BlogTags']/a/text()", multi = true)
     private List<String> tags;
 
-    @ExtractBy("//div[class='BlogStat']/regex('\\d{4}-\\d{1,2}-\\d{1,2} \\d{1,2}:\\d{1,2}')")
-    private Date date;
-
     public static void main(String[] args) {
         OOSpider.create(Site.me().addStartUrl("http://my.oschina.net/flashsword/blog")
                 ,new JsonFilePageModelPipeline(), OschinaBlog.class).run();