myfaces htmlHead不会首先呈现

Question

我已经开始维护旧版JSF应用程序。 它使用myFaces 1.1.x和tomahawk 1.1.6。 我需要打印META标签X-UA-Compatible作为HEAD元素的第一个元素，否则IE将忽略它。

<%@page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" %>
<%@taglib prefix="f" uri="http://java.sun.com/jsf/core"%>
<%@taglib prefix="h" uri="http://java.sun.com/jsf/html"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@taglib prefix="t" uri="http://myfaces.apache.org/tomahawk"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <f:view>
    <t:documentHead>
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta http-equiv="Content-type" content="text/html; charset=UTF-8">

它将产生

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
<script type="text/javascript" src="/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/navmenu.jscookmenu.HtmlJSCookMenuRenderer/JSCookMenu.js"><!--
//--></script>
<script type="text/javascript" src="/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/navmenu.jscookmenu.HtmlJSCookMenuRenderer/MyFacesHack.js"><!--
//--></script>
<script type="text/javascript"><!--
var myThemeMiniBlackBase='/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/navmenu.jscookmenu.HtmlJSCookMenuRenderer/ThemeMiniBlack/';
//--></script>
<script type="text/javascript" src="/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/navmenu.jscookmenu.HtmlJSCookMenuRenderer/ThemeMiniBlack/theme.js"><!--
//--></script>
<link rel="stylesheet" href="/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/navmenu.jscookmenu.HtmlJSCookMenuRenderer/ThemeMiniBlack/theme.css" type="text/css" />
<script type="text/javascript" src="/Viewer/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/15311471/popup.HtmlPopupRenderer/JSPopup.js"><!--
//--></script>
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta http-equiv="Content-type" content="text/html; charset=UTF-8">

如何强制将META标签作为第一个元素？ 我尝试了普通的HTML HEAD元素，但是它也不起作用。

我需要

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta http-equiv="Content-type" content="text/html; charset=UTF-8">

更新：

由于这些标记，呈现了一些JavaScript和样式：

<t:jscookMenu theme="ThemeMiniBlack" layout="hbr" immediate="true">

其余的javascript来自

<t:popup closePopupOnExitingElement="true" closePopupOnExitingPopup="true"
         displayAtDistanceX="10" displayAtDistanceY="20" styleClass="popup">

问题是我是否可以强制执行我在t：documentHead中放置的内容优先？ 我担心我需要写我的自定义标签。

Answer 1

我会尝试自己在自定义Java过滤器中添加meta标签。

<filter>
   <filter-name>MetaTagsFilter</filter-name>
   <filter-class>com.yournamespace.MetaTagsFilter</filter-class>
</filter>

然后为JSF servlet做一个过滤器映射：

<filter-mapping>
   <filter-name>MetaTagsFilter</filter-name>
   <servlet-name>FacesServlet</servlet-name>
</filter-mapping>

<servlet-mapping>
  <servlet-name>FacesServlet</servlet-name>
  <url-pattern>*.faces</url-pattern>
</servlet-mapping>

在您的过滤器逻辑中，在servlet执行处理之后 ，添加meta标签，如下所示：

@Override
public void doFilter(ServletRequest request, ServletResponse response,
        FilterChain filterChain) throws IOException, ServletException {

    HtmlResponseWrapper capturingResponseWrapper = new HtmlResponseWrapper(
            (HttpServletResponse) response);

    filterChain.doFilter(request, capturingResponseWrapper);

    if (response.getContentType() != null
            && response.getContentType().contains("text/html")) {


        // Try this https://stackoverflow.com/a/32830377/1199132
        capturingResponseWrapper.addHeader("X-UA-Compatible", "IE=edge");


        // Or this, that way you have more control over WHERE it gets written
        String content = capturingResponseWrapper.getCaptureAsString();

        // replace stuff here (find the <head></head> tags and add the <meta> at the very beginning)

        System.out.println(replacedContent);

        response.getWriter().write(replacedContent);

    }

}

也可以看看：

• 使用过滤器修改HTML响应
• 在Servlet工作完成之前或之后执行doFilter（）吗？
• 用.jsp或.xhtml或.jsf扩展名创建JSF页面之间有什么区别
• 过滤器要点（Oracle）