Configure an endpoint

An endpoint is the network domain name used to request an API service, for example, ecs.cn-hangzhou.aliyuncs.com.

Alibaba Cloud Classic SDK provides four addressing modes for endpoints. The following list describes them in descending order of priority:

1. User-defined: This addressing logic has the highest priority. It allows you to directly specify the exact endpoint.

   // Takes effect globally
   DefaultProfile.addEndpoint("<RegionID>", "<Product>", "<Endpoint>");
   
   // Takes effect only for the current request
   DescribeRegionsRequest request = new DescribeRegionsRequest();
   request.setSysEndpoint("<Endpoint>");

2. Endpoint concatenation rule: This addressing logic takes effect only when you send a request over a VPC or when the cloud service SDK contains an endpoint data file. Example of an endpoint data file: Ecs Endpoint Data File.

   // Public network request
   request.productNetwork = "public"; // The default value of `productNetwork` is `public`, so you do not need to configure `productNetwork` in most cases
   
   // Cross-domain request
   request.productNetwork = "share";
   
   // IPv6 request
   request.productNetwork = "ipv6";
   
   // Proxy request
   request.productNetwork = "proxy";
   
   // Internal request
   request.productNetwork = "inner";
   
   // IPv4/IPv6 dual-stack request
   request.productNetwork = "dualstack";
   
   // VPC request
   request.productNetwork = "vpc";
   // Alternatively, enable the `enableUsingVpcEndpoint` configuration to access the VPC network
   DefaultProfile profile = DefaultProfile.getProfile("<RegionID>", "<AccessKeyId>", "<AccessKeySecret>");
   profile.enableUsingVpcEndpoint();

3. SDK core addressing: The endpoint is resolved based on the endpoints.json data file in Java SDK Core.

4. Location service addressing: The endpoint is obtained from the remote end by calling the Location service API. This mode requires the cloud service SDK to provide a ServiceCode. It is the primary addressing mode of Alibaba Cloud Classic SDK. However, the Location service supports only public network access. As a result, errors occur easily, which increases the troubleshooting costs for developers.