When a browser requests a service from a web server, an error might occur.
当浏览器向网络服务器请求服务时，有时可能会产生错误。
This is a list of HTTP status messages that might be returned.
下面是所有这些错误所返回的 HTTP 状态消息列表。
1xx: 信息
| 消息 | 描述 |
|---|---|
| 100 Continue | Only a part of the request has been received by the server, but as long as it has not been rejected, the client should continue with the request. 服务器只接受到部分请求，但并没有拒绝，客户应该继续请求。 |
| 101 Switching Protocols | The server switches protocol. 服务器交换机议定书。 |
2xx: 成功
| 消息 | 描述 |
|---|---|
| 200 OK | The request is OK. 请求成功。 |
| 201 Created | The request is complete, and a new resource is created. 请求完成，新资源被建立。 |
| 202 Accepted | The request is accepted for processing, but the processing is not complete. 进程接受请求，但整个进程尚未完毕。 |
| 203 Non-authoritative Information | 文档已经正常地返回，但一些应答头标（HttpServletResponse）可能不正确。 |
| 204 No Content | 没有新的内容，浏览器应该继续显示原来的文档。 |
| 205 Reset Content | 没有新的内容，但浏览器应该重置它所显示的内容。用来强制浏览器清除表单输入内容。 |
| 206 Partial Content | 客户发送了一个带有范围头标（Range）的 GET 请求，服务器已执行完毕。 |
3xx: 重定向
| 消息 | 描述 |
|---|---|
| 300 Multiple Choices | A link list. The user can select a link and go to that location. Maximum five addresses. 连接列表。用户可以通过选择一个链接到达指定的链接位置。最大允许输入5个地址。 |
| 301 Moved Permanently | The requested page has moved to a new url. 请求页切换到一个新的 URL 地址。 |
| 302 Found | The requested page has moved temporarily to a new url. 请求页临时切换到一个新的 URL 地址。 |
| 303 See Other | The requested page can be found under a different url. 请求页可以在另一个 URL 地址中找到。 |
| 304 Not Modified | 客户端有缓冲的文档并发出了一个条件性的请求。 |
| 305 Use Proxy | 客户请求的文档应该通过位置头标（Location）所指明的代理服务器中提取。 |
| 306 Unused | This code was used in a previous version. It is no longer used, but the code is reserved. 该代码仅在先前版本中支持。当前版本已不再支持该代码，但是代码部分仍将保留。 |
| 307 Temporary Redirect | The requested page has moved temporarily to a new url. 请求页临时切换到一个新的 URL 地址。 |
4xx: 客户端错误
| 消息 | 描述 |
|---|---|
| 400 Bad Request | The server did not understand the request. 服务器不能读懂请求。 |
| 401 Unauthorized | The requested page needs a username and a password. 请求页面需要输入用户名和密码。 |
| 402 Payment Required | You can not use this code yet. 不允许在使用这段代码。 |
| 403 Forbidden | Access is forbidden to the requested page. 禁止访问请求页面。 |
| 404 Not Found | The server can not find the requested page. 服务器不能找到请求页面。 |
| 405 Method Not Allowed | The method specified in the request is not allowed. 不允许该请求。 |
| 406 Not Acceptable | The server can only generate a response that is not accepted by the client. 客户端不能接受来自于服务器的回应。 |
| 407 Proxy Authentication Required | You must authenticate with a proxy server before this request can be served. 在处理该请求之前，代理服务器需要认证。 |
| 408 Request Timeout | The request took longer than the server was prepared to wait. 请求超时。 |
| 409 Conflict | The request could not be completed because of a conflict. 请求发生冲突。 |
| 410 Gone | The requested page is no longer available. 请求页已失效。 |
| 411 Length Required | The "Content-Length" is not defined. The server will not accept the request without it. ”Content-Length”尚未定义，因此服务器不能接受该请求。 |
| 412 Precondition Failed | The precondition given in the request evaluated to false by the server. 请求中的预处理过程失败。 |
| 413 Request Entity Too Large | The server will not accept the request, because the request entity is too large. 由于请求实体过大导致服务器不接受该请求。 |
| 414 Request-url Too Long | The server will not accept the request, because the url is too long. Occurs when you convert a "post" request to a "get" request with a long query information. 因为 URL 过长，服务器不接受该请求。当你通过一条较长的查询信息将“post”请求转换为“get”请求时，将会发生该错误。 |
| 415 Unsupported Media Type | The server will not accept the request, because the media type is not supported. 服务器不接受该请求，主要是因为使用的媒体类型不支持。 |
| 416 Requested Range Not Satisfiable | 服务器不能满足客户在范围头标（Range）中所指定的需求。 |
| 417 Expectation Failed | 无法预期执行。 |
5xx: 服务器端错误
| 消息 | 描述 |
|---|---|
| 500 Internal Server Error | The request was not completed. The server met an unexpected condition. 请求未能完成。服务器遭遇意外情况。 |
| 501 Not Implemented | The request was not completed. The server did not support the functionality required. 请求未能完成。服务器不支持该指定的功能。 |
| 502 Bad Gateway | The request was not completed. The server received an invalid response from the upstream server. 请求未能完成。服务器从上游服务器中收到了一个无效回应。 |
| 503 Service Unavailable | The request was not completed. The server is temporarily overloading or down. 请求未能完成。服务器承载量超负荷。 |
| 504 Gateway Timeout | The gateway has timed out. 网关超时。 |
| 505 HTTP Version Not Supported | The server does not support the "http protocol" version. 服务器不支持该 http 协议（http protocal）版本。 |