如何将ResponseEntity写入HttpServletResponse？

Question

如何将ResponseEntity写入HttpServletResponse(因为它使@ResponseBody)？

例如,我有身份验证成功处理程序:

@Override
public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response, Authentication authentication) throws IOException, ServletException {
    Map responseMap = new HashMap();
    responseMap.put("user", "my_user_name");
    ResponseEntity responseEntity = new ResponseEntity(response, HttpStatus.OK);
}

如果使用MappingJackson2HttpMessageConverter我有错误:"无法写入内容:不在非阻塞模式下."

码:

HttpOutputMessage outputMessage = new ServletServerHttpResponse(response);
messageConverter.write(responseEntity, null, outputMessage);

使用HttpServletResponse实现处理程序的最佳实践是什么？

Answer 1

您可以使用自定义响应对象,使用Jackson ObjectMapper将其转换为JSON字符串,并将结果写入请求:

MyResponseObject.java

private String user;

public String getUser() {
    return user;
}

public void setUser(String user) {
    this.user = user;
}

MyAuthenticationSuccessHandler.java

@Override
public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response, Authentication authentication) throws IOException, ServletException {
    MyResponseObject responseObj = new MyResponseObject();
    responseObj.setUser("my_user_name");
    httpServletResponse.setStatus(HttpStatus.OK.value());
    String json = new ObjectMapper().writeValueAsString(responseObj);
    httpServletResponse.getWriter().write(json);
    httpServletResponse.flushBuffer();
}  

Answer 2

基于andrearro88 的回答，我制作了这个通用函数来将 a 复制ResponseEntity到 a HttpServletResponse：

public static void populateResponse(ResponseEntity<String> responseEntity, HttpServletResponse servletResponse)
        throws IOException {
    for (Map.Entry<String, List<String>> header : responseEntity.getHeaders().entrySet()) {
        String chave = header.getKey();
        for (String valor : header.getValue()) {
            servletResponse.addHeader(chave, valor);                
        }
    }

    servletResponse.setStatus(responseEntity.getStatusCodeValue());
    servletResponse.getWriter().write(responseEntity.getBody());
}