Routes Preferred API 目前仅适用于部分客户。如需了解详情，请
与销售人员联系。
FallbackInfo
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
与使用回退结果的方式和原因相关的信息。如果设置了此字段，则表示服务器使用了与您的首选模式不同的路由模式作为后备选项。
如未另行说明，那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可，并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情，请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC)：2025-08-31。
[null,null,["最后更新时间 (UTC)：2025-08-31。"],[[["\u003cp\u003eThe \u003ccode\u003efallbackInfo\u003c/code\u003e field provides insights into why and how a fallback result was utilized during routing.\u003c/p\u003e\n"],["\u003cp\u003eIf present, it indicates the server deviated from the user's preferred routing mode.\u003c/p\u003e\n"],["\u003cp\u003eIt includes \u003ccode\u003eroutingMode\u003c/code\u003e and \u003ccode\u003ereason\u003c/code\u003e fields, specifying the alternative mode used and the cause for fallback.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eroutingMode\u003c/code\u003e field reveals the actual routing mode employed, which might differ from the user's initial preference.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003ereason\u003c/code\u003e field clarifies why the fallback response was necessary.\u003c/p\u003e\n"]]],["The core content details a fallback mechanism used when the server cannot fulfill the preferred routing mode. It provides information in JSON format, including the `routingMode` used for the response and the `reason` for the fallback. The `routingMode` may differ from the client's preference, and the `reason` field explains why an alternate mode was employed. This information is only included when fallback occurs, indicating a deviation from the initial request.\n"],null,["# FallbackInfo\n\n- [JSON representation](#SCHEMA_REPRESENTATION)\n\nInformation related to how and why a fallback result was used. If this field is set, then it means the server used a different routing mode from your preferred mode as fallback.\n\n| JSON representation |\n|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| ``` { \"routingMode\": enum (/maps/documentation/routes_preferred/reference/rest/Shared.Types/FallbackRoutingMode), \"reason\": enum (/maps/documentation/routes_preferred/reference/rest/Shared.Types/FallbackReason) } ``` |\n\n| Fields ||\n|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| `routing``Mode` | `enum (`[FallbackRoutingMode](/maps/documentation/routes_preferred/reference/rest/Shared.Types/FallbackRoutingMode)`)` Routing mode used for the response. If fallback was triggered, the mode may be different from routing preference set in the original client request. |\n| `reason` | `enum (`[FallbackReason](/maps/documentation/routes_preferred/reference/rest/Shared.Types/FallbackReason)`)` The reason why fallback response was used instead of the original response. This field is only populated when the fallback mode is triggered and the fallback response is returned. |"]]
