错误:在方法中引发新的ResponseStatusException时缺少返回语句

import org.springframework.web.server.ResponseStatusException;
import org.springframework.http.HttpStatus;

public class ExampleService {
    public String processRequest() {
        try {
            // 执行业务逻辑
            // 如果需要返回特定的HTTP状态码，可以抛出ResponseStatusException异常
            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "请求参数错误");
        } catch (ResponseStatusException ex) {
            // 捕获ResponseStatusException异常
            HttpStatus statusCode = ex.getStatus();
            String errorMessage = ex.getReason();

            // 根据状态码选择合适的处理逻辑
            if (statusCode == HttpStatus.BAD_REQUEST) {
                // 处理400错误
                return "请求参数错误：" + errorMessage;
            } else if (statusCode == HttpStatus.NOT_FOUND) {
                // 处理404错误
                return "资源未找到：" + errorMessage;
            } else {
                // 其他状态码的处理逻辑
                return "发生错误：" + errorMessage;
            }
        }
    }
}