迁移至Spring6+Tomcat10.1后JSTL标签[c]无法找到的问题

问题背景 #

将项目从Tomcat 9 + Java EE迁移至Spring 6.0.11 + Tomcat 10.1.13后，JSTL标签无法正常使用。已按Jakarta Standard Tag Library 3.0规范，将所有JSP中的标签库URI从http://java.sun.com/jsp/jstl/core修改为jakarta.tags.core，但调试发现TldCache中的URI映射未填充，导致TagLibraryInfoImpl的tldResourcePath为null，最终抛出标签库找不到的异常。

当前依赖配置 #

implementation 'jakarta.servlet.jsp.jstl:jakarta.servlet.jsp.jstl-api:3.0.0'
implementation 'org.glassfish.web:jakarta.servlet.jsp.jstl:3.0.1'
implementation 'org.mortbay.jasper:apache-jsp:10.1.7'
implementation("org.apache.tomcat:tomcat-jsp-api:10.1.13")
compileOnly "jakarta.servlet:jakarta.servlet-api:6.0.0"

抛出的异常信息 #

org.apache.jasper.JasperException: Could not find taglib [c] for URI: [jakarta.tags.core]
    in org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:54)
    in org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:294)
    in org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:81)
    in org.apache.jasper.compiler.TagLibraryInfoImpl.<init>(TagLibraryInfoImpl.java:176)
    in org.apache.jasper.compiler.Parser.parseTaglibDirective(Parser.java:429)
    in org.apache.jasper.compiler.Parser.parseDirective(Parser.java:487)
    in org.apache.jasper.compiler.Parser.parseElements(Parser.java:1444)
    in org.apache.jasper.compiler.Parser.parse(Parser.java:138)
    in org.apache.jasper.compiler.ParserController.doParse(ParserController.java:245)
    in org.apache.jasper.compiler.ParserController.parse(ParserController.java:106)
    in org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:211)
    in org.apache.jasper.compiler.Compiler.compile(Compiler.java:396)
    in org.apache.jasper.compiler.Compiler.compile(Compiler.java:372)
    in org.apache.jasper.compiler.Compiler.compile(Compiler.java:356)
    in org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:603)
    in org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:396)
    in org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:380)
    in org.apache.jasper.servlet.JspServlet.service(JspServlet.java:328)
    in jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658)
    in org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:205)
    in org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149)
    in org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
    in org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174)
    in org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149)
    in org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:110)
    in org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174)
    in org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149)

已尝试的额外依赖（未解决问题） #

compileOnly 'jakarta.servlet.jsp:jakarta.servlet.jsp-api:3.1.1'
implementation 'org.mortbay.jasper:taglibs-standard:10.0.2'
compileOnly 'jakarta.platform:jakarta.jakartaee-api:10.0.0'

排查方向与解决方案 #

1. 移除冲突依赖：Tomcat 10.1自带适配Jakarta EE 10的Jasper编译器，额外引入org.mortbay.jasper:apache-jsp会导致类加载冲突，覆盖原生TLD加载逻辑。同时tomcat-jsp-api为Tomcat自带依赖，需一并移除。

2. 检查JSTL实现包的TLD映射：确认org.glassfish.web:jakarta.servlet.jsp.jstl:3.0.1包内包含：

   • META-INF/c.tld文件，且文件内<uri>标签值为jakarta.tags.core
   • META-INF/tld-index.xml中已注册该URI与TLD的关联

3. 精简后的依赖配置：

   implementation 'jakarta.servlet.jsp.jstl:jakarta.servlet.jsp.jstl-api:3.0.0'
   implementation 'org.glassfish.web:jakarta.servlet.jsp.jstl:3.0.1'
   compileOnly 'jakarta.servlet:jakarta.servlet-api:6.0.0'
   compileOnly 'jakarta.servlet.jsp:jakarta.servlet.jsp-api:3.1.1'
   

4. 验证Web应用配置：确保web.xml使用Jakarta EE 10的命名空间与版本：

   <web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee https://jakarta.ee/xml/ns/jakartaee/web-app_6_0.xsd"
            version="6.0">
   

5. TLD加载机制说明：Apache Jasper通过扫描classpath下所有jar中的META-INF/*.tld文件和META-INF/tld-index.xml建立URI到TLD的映射，这些映射会自动缓存到TldCache中，无依赖冲突时即可正常填充。

内容的提问来源于stack exchange，提问作者Vooply