Java servlet筛选器在登录时不起作用

我编写了一个过滤器类，在每个页面上添加一个P3P标题。我在我的web.xml中添加了以下内容：

AddP3pHeaderFilter
com.mycompany.AddP3pHeaderFilter
AddP3pHeaderFilter
/*

---

它会将标头添加到每个页面请求中，但当用户首次登录时，它不起作用。用户将表单提交到

j_security_check

，但响应不包括标题。如何将筛选应用于登录请求？

登录请求将转发到相应页面。默认情况下，筛选器仅适用于请求分派。您需要修改web.xml，如下所示：

AddP3pHeaderFilter
com.mycompany.AddP3pHeaderFilter
AddP3pHeaderFilter
/*
要求
向前地

编辑：我以为这已经解决了问题，但我错了。

---

最后我不得不使用Tomcat阀门。

由于安全原因，大多数servletcontainers确实不允许在

/j_security\u check

请求上挂起钩子。一些较旧的版本可以，但应该在较新的版本中修复

无论如何，最好的方法是检查用户主体是否存在于

HttpSession

中，如果用户主体不存在，则手动将其放在那里

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {
    HttpServletRequest httpRequest = (HttpServletRequest) request;
    UserPrincipal user = httpRequest.getUserPrincipal();
    HttpSession session = httpRequest.getSession();
    if (user != null && session.getAttribute("user") == null) {
        session.setAttribute("user", user);

        // First-time login. You can do your intercepting thing here.
    }
    chain.doFilter(request, response);
}

---

我不知道tomcat的情况，但它在jetty中对我有效，只需将过滤器放在弹簧过滤器之前：

<filter>
    <filter-name>AddP3pHeaderFilter</filter-name>
    <filter-class>com.mycompany.AddP3pHeaderFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>AddP3pHeaderFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>

<filter-mapping>
  <filter-name>springSecurityFilterChain</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

AddP3pHeaderFilter
com.mycompany.AddP3pHeaderFilter
AddP3pHeaderFilter
/*
springSecurityFilterChain
org.springframework.web.filter.DelegatingFilterProxy
springSecurityFilterChain
/*

My web.xml

<filter>
        <description>
        FBIS Filter</description>
        <display-name>Fbisfilter</display-name>
        <filter-name>Fbisfilter</filter-name>
        <filter-class>fbis.filter.Fbisfilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>Fbisfilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

---

+1：用于向社区Drat添加可搜索的知识。实际上我的解决方案不起作用，所以我想这毕竟是一个正常的问题。如果我没记错的话，doFilter方法在用户登录时甚至没有被调用。我将用我最终的所作所为更新我已接受的答案。

package fbis.filter;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.sqlconnection.SQLConnect;
import com.sun.security.auth.UserPrincipal;

import fbis.interfaces.abstractclasses.Connections;

/**
 * Servlet Filter implementation class Fbisfilter
 */
public class Fbisfilter extends Object implements Filter,Connections {
    public void destroy() {
    //  System.out.println("Filter Service finished");
    }
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpresponse = (HttpServletResponse) response;
        System.out.println("FILTER INSIDE");
    // place your code here
        HttpSession session = httpRequest.getSession(true);
        String usrid = httpRequest.getParameter("txtuname");
        String pwd = httpRequest.getParameter("txtpassword");
        PreparedStatement pstmt;
        try {
            pstmt = con
                    .prepareStatement("SELECT l.Userid,n.First_name from Login_details_dtls l join New_Registration_dtls n on l.Userid=n.Userid where n.Userid=? AND l.pwd=?");
        pstmt.setString(1, usrid);
        pstmt.setString(2, pwd);
        ResultSet rs = pstmt.executeQuery();
        if (rs.next()) {
            session.setAttribute("usr", rs.getString("Userid"));
            session.setAttribute("usrname", rs.getString("First_name"));
        }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        chain.doFilter(httpRequest, httpresponse);
    }

    /**
     * @see Filter#init(FilterConfig)
     */
    public void init(FilterConfig fConfig) throws ServletException {
        System.out.println("Filter Service has started");
    }

}