这是我的WebFilter
的样子
@WebFilter("/rest/*")
public class AuthTokenValidatorFilter implements Filter {
@Override
public void init(final FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(final ServletRequest servletRequest, final ServletResponse servletResponse, final FilterChain filterChain) throws IOException, ServletException {
final Enumeration<String> attributeNames = servletRequest.getAttributeNames();
while (attributeNames.hasMoreElements()) {
System.out.println("{attribute} " + servletRequest.getParameter(attributeNames.nextElement()));
}
final Enumeration<String> parameterNames = servletRequest.getParameterNames();
while (parameterNames.hasMoreElements()) {
System.out.println("{parameter} " + servletRequest.getParameter(parameterNames.nextElement()));
}
filterChain.doFilter(servletRequest, servletResponse);
}
@Override
public void destroy() {
}
}
我试图在网上找到如何从请求中获取HTTP headers
的值。
我没有找到任何东西,所以我试图在servletRequest.getAttributeNames()
和servletRequest.getParameterNames()
上列举而不知道任何事情,但我没有得到任何标题。
题 如何从请求中获取所有标头?
Typecast ServletRequest
进入HttpServletRequest
(仅当ServletRequest request
是instanceof
HttpServletRequest
时)。
然后你可以使用HttpServletRequest.getHeader()
和HttpServletRequest.getHeaderNames()
方法。
像这样的东西:
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest) request;
Enumeration<String> headerNames = httpRequest.getHeaderNames();
if (headerNames != null) {
while (headerNames.hasMoreElements()) {
System.out.println("Header: " + httpRequest.getHeader(headerNames.nextElement()));
}
}
//doFilter
chain.doFilter(httpRequest, response);
}
使用Java 8,您可以使用流来收集请求标头:
HttpServletRequest httpRequest = (HttpServletRequest) request;
Map<String, String> headers = Collections
.list(httpRequest.getHeaderNames())
.stream()
.collect(Collectors.toMap(h -> h, httpRequest::getHeader));
更新
@Matthias提醒我有可能为一个标题赋予多个值:
Map<String, List<String>>
Map<String, List<String>> headersMap = Collections
.list(httpRequest.getHeaderNames())
.stream()
.collect(Collectors.toMap(
Function.identity(),
h -> Collections.list(httpRequest.getHeaders(h))
));
HttpHeaders
HttpHeaders httpHeaders = Collections
.list(httpRequest.getHeaderNames())
.stream()
.collect(Collectors.toMap(
Function.identity(),
h -> Collections.list(r.getHeaders(h)),
(oldValue, newValue) -> newValue,
HttpHeaders::new
));
https://gist.github.com/Cepr0/fd5d9459f17da13b29126cf313328fe3
您应该考虑使用不同的值多次出现相同的HTTP标头:
Map<String, Serializable> headers = Collections.list(request.getHeaderNames()).stream().collect(Collectors.toMap(h -> h, h -> {
ArrayList<String> headerValues = Collections.list(request.getHeaders(h));
return headerValues.size() == 1 ? headerValues.get(0) : headerValues;
}));