Fix deprecated JSTL namespaces and upgrade to JSTL 1.2 for Tomcat 9 compatibility

[Copilot]

JSP files were using deprecated JSTL 1.0 namespaces (http://java.sun.com/jstl/core_rt, http://java.sun.com/jstl/fmt_rt) and the obsolete Acegi Security taglib, causing JasperException failures when rendering pages. The old JSTL 1.1.2 dependencies also lacked the Tag Library Descriptor (TLD) files required by Tomcat 9 to resolve modern JSTL namespaces.

Changes

JSP Namespace Updates

• taglibs.jsp: Updated to modern JSTL namespaces and Spring Security taglib

  • http://java.sun.com/jstl/core_rt → http://java.sun.com/jsp/jstl/core
  • http://java.sun.com/jstl/fmt_rt → http://java.sun.com/jsp/jstl/fmt
  • http://acegisecurity.org/authz → http://www.springframework.org/security/tags (prefix changed from authz to sec)

• error.jsp / error-500.jsp: Fixed incomplete JSTL namespaces

  • http://java.sun.com/jstl/core → http://java.sun.com/jsp/jstl/core
  • http://java.sun.com/jstl/fmt → http://java.sun.com/jsp/jstl/fmt

JSTL Dependency Upgrade (pom.xml)

Upgraded JSTL from 1.1.2 to 1.2 to provide TLD files for modern namespaces required by Tomcat 9:

• javax.servlet:jstl: Upgraded from 1.1.2 to 1.2 (JSTL API)
• org.glassfish.web:jstl-impl:1.2: Added implementation containing TLD files that define modern namespace URIs (http://java.sun.com/jsp/jstl/core, http://java.sun.com/jsp/jstl/fmt, etc.)
• taglibs:standard:1.1.2: Commented out (functionality included in jstl-impl)

The jstl-impl JAR includes the necessary TLD files (META-INF/c.tld, META-INF/fmt.tld) that were missing in JSTL 1.1.2, resolving the "cannot be resolved in either web.xml or the jar files" error.

Verification

All 208 JSP files checked; no other deprecated namespaces found. Build succeeds and WAR file includes proper JSTL 1.2 JARs with TLD files.

Original prompt

The JSPs are very outdated, including references to namespaces that are probably deprecated. This leads to this error (in the web UI):

org.apache.jasper.JasperException: /index.jsp (line: [1], column: [1]) The absolute uri: [http://java.sun.com/jstl/core_rt] cannot be resolved in either web.xml or the jar files deployed with this application
	org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:29)
	org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:265)
	org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:88)
	org.apache.jasper.compiler.Parser.processIncludeDirective(Parser.java:334)
	org.apache.jasper.compiler.Parser.parseIncludeDirective(Parser.java:364)
	org.apache.jasper.compiler.Parser.parseDirective(Parser.java:455)
	org.apache.jasper.compiler.Parser.parseElements(Parser.java:1353)
	org.apache.jasper.compiler.Parser.parse(Parser.java:132)
	org.apache.jasper.compiler.ParserController.doParse(ParserController.java:240)
	org.apache.jasper.compiler.ParserController.parse(ParserController.java:103)
	org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:186)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:359)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:337)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:323)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:371)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:349)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:300)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:623)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)

Do a thorough review of all JSP files and upgrade any such deprecated features.

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[rvosa]

@copilot I still get a similar error, despite the updated namespace:

org.apache.jasper.JasperException: /index.jsp (line: [1], column: [1]) The absolute uri: [http://java.sun.com/jsp/jstl/core] cannot be resolved in either web.xml or the jar files deployed with this application
	org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:29)
	org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:265)
	org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:88)
	org.apache.jasper.compiler.Parser.processIncludeDirective(Parser.java:334)
	org.apache.jasper.compiler.Parser.parseIncludeDirective(Parser.java:364)
	org.apache.jasper.compiler.Parser.parseDirective(Parser.java:455)
	org.apache.jasper.compiler.Parser.parseElements(Parser.java:1353)
	org.apache.jasper.compiler.Parser.parse(Parser.java:132)
	org.apache.jasper.compiler.ParserController.doParse(ParserController.java:240)
	org.apache.jasper.compiler.ParserController.parse(ParserController.java:103)
	org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:186)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:359)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:337)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:323)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:371)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:349)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:300)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:623)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)

Could something else be going on?

[Copilot]

@copilot I still get a similar error, despite the updated namespace:

...

The issue was that while the namespaces were correct, the old JSTL 1.1.2 JARs didn't include the TLD (Tag Library Descriptor) files for the modern http://java.sun.com/jsp/jstl/core namespace.

I've upgraded the JSTL dependencies from 1.1.2 to 1.2 in commit 47379a8, which includes:

• javax.servlet:jstl:1.2 (JSTL API)
• org.glassfish.web:jstl-impl:1.2 (implementation with proper TLD files)

The jstl-impl-1.2.jar now includes the TLD files that define the modern namespaces, which Tomcat 9 requires. This should resolve the "cannot be resolved" error.