cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration can be found for element

- cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration can be found for element 'dubbo:application'.
    - 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 .

在写dubbo项目的时候，每次在不同项目空间上重新写分布式dubbo项目都会出现以上错误信息在applicationProvider.xml文件上。

解决方法如下:

1、窗口(windows)->首选项(preference)

2、在搜索框中输入xml就你能看见下面的截图效果，单击Xml Catalog,单击添加

3、先要下载dubbo.xsd文件，然后单击文件系统选择该文件，把键类型改为模式位置(schema location)，重点是把键(Key)改为http://code.alibabatech.com/schema/dubbo/dubbo.xsd，然后单击确定，

4、单击项目(project)下的 清理(clean)

5、dubbo.xsd下载