From 27ce3fc17660dc5c2bf3f8c32cf6e4fc55525ab2 Mon Sep 17 00:00:00 2001
From: "yihua.huang" <code4crafter@gmail.com>
Date: Mon, 5 Aug 2013 19:36:49 +0800
Subject: [PATCH] lazy init

---
 .../src/main/java/us/codecraft/webmagic/Request.java      | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/webmagic-core/src/main/java/us/codecraft/webmagic/Request.java b/webmagic-core/src/main/java/us/codecraft/webmagic/Request.java
index 9b9740d..77db2c1 100644
--- a/webmagic-core/src/main/java/us/codecraft/webmagic/Request.java
+++ b/webmagic-core/src/main/java/us/codecraft/webmagic/Request.java
@@ -33,7 +33,7 @@ public class Request {
     /**
      * 额外参数，可以保存一些需要的上下文信息
      */
-    private Map<String, Object> extras = new HashMap<String, Object>();
+    private Map<String, Object> extras;
 
     private double priority;
 
@@ -56,10 +56,16 @@ public class Request {
     }
 
     public Object getExtra(String key) {
+        if (extras==null){
+            return null;
+        }
         return extras.get(key);
     }
 
     public Request putExtra(String key,Object value) {
+        if (extras==null){
+            extras = new HashMap<String, Object>();
+        }
         extras.put(key,value);
         return this;
     }