AWS SNS / SnsClient可以支持使用UTF-8字符发送短信消息。

以下是一个Java代码示例，演示如何使用SnsClient发送包含UTF-8字符的短信消息：

import com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.sns.AmazonSNS;
import com.amazonaws.services.sns.AmazonSNSClientBuilder;
import com.amazonaws.services.sns.model.PublishRequest;
import com.amazonaws.services.sns.model.PublishResult;

public class SnsUTF8MessageExample {

    public static void main(String[] args) {
        String accessKey = "YOUR_ACCESS_KEY";
        String secretKey = "YOUR_SECRET_KEY";
        String topicArn = "YOUR_TOPIC_ARN";
        String message = "你好，世界！";

        // 创建SnsClient
        AmazonSNS snsClient = AmazonSNSClientBuilder.standard()
                .withRegion(Regions.US_EAST_1)
                .withCredentials(new AWSStaticCredentialsProvider(new BasicAWSCredentials(accessKey, secretKey)))
                .build();

        // 创建PublishRequest
        PublishRequest publishRequest = new PublishRequest()
                .withTopicArn(topicArn)
                .withMessage(message)
                .withSubject("测试消息")
                .withMessageAttributes(null);

        // 发送短信消息
        PublishResult result = snsClient.publish(publishRequest);

        // 打印消息ID
        System.out.println("Message sent. Message ID: " + result.getMessageId());
    }
}

请确保将YOUR_ACCESS_KEY和YOUR_SECRET_KEY替换为您的AWS访问密钥，并将YOUR_TOPIC_ARN替换为您要发送消息的SNS主题ARN。

该示例中的message变量使用了UTF-8编码的字符串“你好，世界！”。您可以根据需要更改消息内容。

这样，您就可以使用SnsClient发送包含UTF-8字符的短信消息了。