在Spring Boot web Thymeleaf应用程序中进行AJAX调用的正确方式已经为此响应调用了getOutputStream()

@RestController
public class MyController {

    @RequestMapping("/ajax-call")
    public String handleAjaxCall() {
        // 处理AJAX调用的逻辑
        return "Hello AJAX!";
    }
}

@RestController
public class MyController {

    @RequestMapping("/ajax-call")
    public String handleAjaxCall(HttpServletResponse response) throws IOException {
        response.setContentType("text/plain");
        response.setCharacterEncoding("UTF-8");
        
        PrintWriter writer = response.getWriter();
        writer.write("Hello AJAX!");
        writer.flush();
        writer.close();
        
        return null;
    }
}