背景混合模式所有属性 - 无论代码示例 代码示例2 To reflect the status as of 2015: Behaviorally both 400 and 422 response codes will be treated the same by clients and intermediaries, so it actually doesn't make a concrete difference which you use. However I would expect to see 400 currently...
实际上，JAXRS服务器框架实际上是一个服务器框架;-)这意味着它实际上没有按照客户端发送正确的内容。
a链接没有src属性, 应该改为href,即: 下载文件