cannot load JSTL taglib within embedded Jetty server

java jetty jstl taglib embedded-jetty

23,720

Solution 1

Jetty 8.0, which has pushed as the default when you use jetty:run, has servlet API 3.0. As of that version of the standard, JSTL standard is supposed to be included, and these taglibs cannot be in the webapp classpath, only the standard classpath. However, 8.0.0.M0 forgot to include them.

Specifying 7.1.4.v20100610 helped for me.

Solution 2

The jstl taglibs must be on server classpath. You can add a classloader to current classloader chain before start the server. That's the principle used by start.jar when it start a jetty server.

ClassLoader currentClassLoader = Thread.currentThread().getContextClassLoader();
URL urlTaglibs = new File(PATH_TO_TAGLIBS).toURI().toURL();
URLClassLoader newClassLoader = new URLClassLoader(new URL[]{urlTaglibs},currentClassLoader);
Thread.currentThread().setContextClassLoader(newClassLoader);

server.start();

You should also add it to java start command line argument.

Solution 3

jstl-1.2.jar

standard-1.1.2.jar

This collides. Remove the standard-1.1.2.jar. You should use standard-1.1.2.jar only with jstl-1.1.2.jar. Since JSTL 1.2 the standard JAR has been merged into JSTL JAR, resulting in a single jstl-1.2.jar file.

Solution 4

@Drew Thanks Drew. It works.I had been googling for this and end up here.What my mistake was : I was using

                 <dependency>
                    <groupId>javax.servlet</groupId>
                    <artifactId>jstl</artifactId>
                     <version>1.1.2</version>
                     <scope>provided</scope>
                </dependency>

I changed it from above to

           <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
             <version>1.2</version>
             <scope>provided</scope>
        </dependency>

and it got working. Also I was using jstls dependency which I removed.

Solution 5

I got the same problem on Jetty 7, I solved it by enabling Jetty to search for TLD:

I did it by setting an attribute on the context:

Server server = new Server(80);  
WebAppContext context = new WebAppContext("pig-1.0-SNAPSHOT.war","/");
context.setAttribute("org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern", 
    ".*/.*jsp-api-[^/]*\\.jar$|.*/.*jsp-[^/]*\\.jar$|.*/.*taglibs[^/]*\\.jar$");
server.addHandler(context);
server.start();

Refer to http://wiki.eclipse.org/Jetty/Howto/Configure_JSP#Using_JSTL_Taglibs_for_Jetty_7.x_and_8.x for further details.

On my project (using maven), I have standard TLDs are on the JAR "org.apache.taglibs.standard.glassfish-1.2.0.v2011120803.jar" and theoretically it would be enough to use as value for ContainerIncludeJarPattern the following pattern:

".*/org\\.apache\\.taglibs\\.standard\\.glassfish-1\\.2\\.0\\.v201112081803\\.jar"

It actually works and it is a confirmation of where do jetty found the tag libs, but I've preferred to leave the previous pattern which I found on the wiki.eclipse.org page linked above.

It may be required to extend the pattern if you want to include custom tag libs.

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23,720

Author by

Admin

Updated on April 07, 2020

Comments

Admin about 4 years
I am writing a web application that runs within an embedded Jetty instance.

When I attempt to execute a JSTL statement, I receive the following exception:

org.apache.jasper.JasperException: /index.jsp(1,63) PWC6188: 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

I have the following jars on the classpath
- ant-1.6.5.jar
- ant-1.7.1.jar
- ant-launcher-1.7.1.jar
- core-3.1.1.jar
- jetty-6.1.22.jar
- jetty-util-6.1.22.jar
- jsp-2.1-6.1.14.jar
- jsp-api-2.1.jar
- jstl-1.2.jar
- servlet-api-2.5-20081211.jar
- servlet-api-2.5-6.1.14.jar
- standard-1.1.2.jar
My web.xml looks like this:
```
<?xml version="1.0" encoding="ISO-8859-1"?>  
    <web-app xmlns="http://java.sun.com/xml/ns/j2ee"  
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee h77p://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"  
    version="2.4">  
    <display-name>test</display-name>  
</web-app>
```
My code looks like this:
```
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>  
<html>  
    <body>  
        <h2>Hello World!</h2>  
        <%= new java.util.Date() %><br/>  
        ${1+2}<br/>  
        <c:out var="${5+9}"/><br/>  
    </body>  
</html>
```
I started my embedded Jetty server like this:
```
Server server = new Server(80);  
WebAppContext context = new WebAppContext("pig-1.0-SNAPSHOT.war","/");
server.addHandler(context);
server.start();
```
I spent the past two days experimenting with various combinations of jar files, web.xml configurations, and tag library declarations, but to no avail.

How can I get an embedded Jetty server up and running with full JSTL support?