添加搜索后端接口

Change-Id: Ie7d87009f4b71ebdf3fdb30f561d4cf85bc6f416
diff --git a/src/main/java/database/Database2.java b/src/main/java/database/Database2.java
index d7c5eee..0166081 100644
--- a/src/main/java/database/Database2.java
+++ b/src/main/java/database/Database2.java
@@ -1116,4 +1116,9 @@
     public PostReply[] GetPostReplyList(String postid) {
         return null;
     }
+
+    @Override
+    public Post[] SearchPost(String userQ) {
+        return null;
+    }
 }
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