cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration

dubbo配置文件上会有红叉叉,不影响项目运行，但还是看的不爽，项目中用maven依赖dubbo-2.4.9.jar。错误详情：

Multiple annotations found at this line:
    - cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration can be found for element 'dubbo:reference'.
    - schema_reference.4: Failed to read schema document 'http://code.alibabatech.com/schema/dubbo/dubbo.xsd', because 
     1) could not find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>.

解决办法： 
1，找到maven仓库下dubbo-2.4.9.jar的目录

locate dubbo-2.4.9.jar

会返回类似的路径 
/home/evan/maven_repository/com/alibaba/dubbo/2.4.9/dubbo-2.4.9.jar

2,在命令行中跳转到dubbo-2.4.9.jar所在目录，解压dubbo-2.4.9.jar文件

cd /home/evan/maven_repository/com/alibaba/dubbo/2.4.9/
jar xf dubbo-2.4.9.jar

3，在eclipse中window–preferences–XML–XML Catalog 右边界面add按钮后会出现一个新的界面 
选择file system 将刚才解压文件中 META-INF/dubbo.xsd选中 
需要注意两点 
1）key type 选择 schema location （默认是Namespace name) 
2)key 一定要写http://code.alibabatech.com/schema/dubbo/dubbo.xsd 
（默认http://code.alibabatech.com/schema/dubbo） 

4，在项目上右键点击Validate即可 （如果dubbo配置文件很少，推荐在具体xml文件上右键Validate,这样可以时间短一些）