java - 使用 HTTPServletRequestWrapper 包装请求参数

Question

我有一个过滤器可以验证/授权 REST 调用。此过滤器需要访问请求参数，因此我为此编写了自定义 HTTPServletRequestWrapper。

import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

public class WrapperRequest extends HttpServletRequestWrapper {
    private Map<String, String[]> requestParams = null;

    public WrapperRequest(final ServletRequest request) {
        super((HttpServletRequest) request);

    }

    @Override
    public String getParameter(final String name) {
        if (getParameterMap().get(name) != null) {
            return getParameterMap().get(name)[0];
        } else {
            getParameterMap().get(name)[0] = super.getParameter(name);
            requestParams.put(name, getParameterMap().get(name));
            return requestParams.get(name)[0];
        }

    }

    @Override
    public Map<String, String[]> getParameterMap() {
        if (requestParams == null) {
            requestParams = new HashMap<String, String[]>();
            requestParams.putAll(super.getParameterMap());
        }
        return Collections.unmodifiableMap(requestParams);
    }

    @Override
    public Enumeration<String> getParameterNames() {
        return Collections.enumeration(getParameterMap().keySet());
    }

    @Override
    public String[] getParameterValues(final String name) {
        return getParameterMap().get(name);
    }
}

在我的过滤器 doFilter 方法中:

public void doFilter(ServletRequest request, ServletResponse response,
        FilterChain chain) throws IOException, ServletException {


    final WrapperRequest wrappedRequest = new WrapperRequest(request);
    Map<String, String[]> paramMap = wrappedRequest.getParameterMap();
    chain.doFilter(wrappedRequest, response);

但我收到以下警告

WARNING: A servlet request, to the URI , contains form parameters in the request body but the request body has been consumed by the servlet or a servlet filter accessing the request parameters. Only resource methods using @FormParam will work as expected. Resource methods consuming the request body by other means will not work as expected.

我正在 Tomcat 中部署它。帮助!

Answer 1

我认为您正在将 Jersey 用于 REST 框架？

我认为这基本上是说，由于 Servlet 现在已经构造了 Request 对象，因此 Jersey 现在无法区分表单参数和查询字符串参数之间的区别。

有关详细信息，请参阅:https://issues.apache.org/jira/browse/STANBOL-437

这引出了一个问题 - 这实际上会给您带来问题还是您只是担心警告消息？