I don't know what I've done incorrectly, but I can't include JSTL. I have jstl-1.2.jar, but unfortunately I get exception:

org.apache.jasper.JasperException: The absolute uri: http://java.sun.com/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application
    at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:51)
    at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:409)
    at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:116)
    at org.apache.jasper.compiler.TagLibraryInfoImpl.generateTLDLocation(TagLibraryInfoImpl.java:315)
    at org.apache.jasper.compiler.TagLibraryInfoImpl.<init>(TagLibraryInfoImpl.java:148)
    at org.apache.jasper.compiler.Parser.parseTaglibDirective(Parser.java:429)
    at org.apache.jasper.compiler.Parser.parseDirective(Parser.java:492)
    at org.apache.jasper.compiler.Parser.parseElements(Parser.java:1439)
    at org.apache.jasper.compiler.Parser.parse(Parser.java:137)
    at org.apache.jasper.compiler.ParserController.doParse(ParserController.java:255)
    at org.apache.jasper.compiler.ParserController.parse(ParserController.java:103)
    at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:170)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:332)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:312)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:299)
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:586)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
    at java.lang.Thread.run(Thread.java:619)

I have:

pom.xml

<dependency>
  <groupId>javax.servlet</groupId>
  <artifactId>servlet-api</artifactId>
  <version>2.5</version>
  <scope>provided</scope>
</dependency>
<dependency>
  <groupId>javax.servlet.jsp</groupId>
  <artifactId>jsp-api</artifactId>
  <version>2.1</version>
  <scope>provided</scope>
</dependency>

<dependency>
  <groupId>taglibs</groupId>
  <artifactId>standard</artifactId>
  <version>1.1.2</version>
</dependency>
<dependency开发者_运维问答>
  <groupId>javax.servlet</groupId>
  <artifactId>jstl</artifactId>
  <version>1.2</version>
</dependency>

web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
  version="2.5">

index.jsp

<%@ taglib uri="http://java.sun.com/jstl/core" prefix="c" %>
<html> 
<head></head>
<body></body>
</html>

org.apache.jasper.JasperException: The absolute uri: http://java.sun.com/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application

That URI is for JSTL 1.0, but you're actually using JSTL 1.2 which uses URIs with an additional /jsp path (because JSTL, who invented EL expressions, was since version 1.1 integrated as part of JSP 2.0 (released way back in 2001!) in order to share/reuse the EL logic in plain JSP too).

So, fix the taglib URI accordingly based on JSTL 1.2 documentation:

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

Further you need to make absolutely sure that you do not throw multiple different versioned JSTL JAR files together into the runtime classpath. This is a pretty common mistake among Tomcat users. The problem with Tomcat is that it does not offer JSTL out the box and thus you have to manually install it. This is not necessary in normal Jakarta EE servers. See also What exactly is Java EE?

In your specific case, your pom.xml basically tells you that you have jstl-1.2.jar and standard-1.1.2.jar together. This is wrong. You're basically mixing JSTL 1.2 API+impl from Oracle with JSTL 1.1 impl from Apache. You should stick to only one JSTL implementation and the API version must match the impl version.

Installing JSTL on Tomcat 10.1.x

In case you're already on Tomcat 10.1.x (the second Jakartified version, with jakarta.* package instead of javax.* package, but the first version with the updated jakarta.tags.* namespace URNs instead of http://java.sun.com/jsp/jstl/* namespace URLs), use JSTL 3.0 via this sole dependency using the default Maven scope of compile (because Tomcat doesn't provide it out the box!):

<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>3.0.1</version>
</dependency>

Note that the API dependency is already transitively included via this impl dependency, so you do not need to explicitly declare it.

Non-Maven users can achieve the same by dropping the following two physical files in /WEB-INF/lib folder of the web application project (do absolutely not drop standard*.jar or any loose .tld files in there! remove them if necessary).

jakarta.servlet.jsp.jstl-3.0.1.jar (this is the JSTL 3.0.1 impl of EE4J)
jakarta.servlet.jsp.jstl-api-3.0.0.jar (this is the JSTL 3.0 API)

As said, the namespace URIs have been changed to become URNs instead of URLs. JSTL core is since JSTL version 3.0 available via an easier to remember namespace URI in URN format:

<%@ taglib prefix="c" uri="jakarta.tags.core" %>

Installing JSTL on Tomcat 10.0.x

In case you're on Tomcat 10.0.x (the first Jakartified version, with jakarta.* package instead of javax.* package), use JSTL 2.0 via this sole dependency using the default Maven scope of compile (because Tomcat doesn't provide it out the box!):

<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>2.0.0</version>
</dependency>

Note that the API dependency is already transitively included via this impl dependency, so you do not need to explicitly declare it.

jakarta.servlet.jsp.jstl-2.0.0.jar (this is the JSTL 2.0 impl of EE4J)
jakarta.servlet.jsp.jstl-api-2.0.0.jar (this is the JSTL 2.0 API)

Installing JSTL on Tomcat 9-

In case you're not on Tomcat 10 yet, but still on Tomcat 9 or older, use JSTL 1.2 via this sole dependency (this is compatible with Tomcat 9 / 8 / 7 / 6 / 5 but not older) using the default Maven scope of compile (because Tomcat doesn't provide it out the box!):

<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>1.2.6</version>
</dependency>

Note that the API dependency is already transitively included via this impl dependency, so you do not need to explicitly declare it.

jakarta.servlet.jsp.jstl-1.2.6.jar (this is the JSTL 1.2 impl of EE4J)
jakarta.servlet.jsp.jstl-api-1.2.7.jar (this is the JSTL 1.2 API)

Installing JSTL on normal JEE server

In case you're actually using a normal Jakarta EE server such as WildFly, Payara, TomEE, GlassFish, WebSphere, OpenLiberty, WebLogic, etc instead of a barebones servletcontainer such as Tomcat, Jetty, Undertow, etc, then you do not need to explicitly install JSTL at all. Normal Jakarta EE servers already provide JSTL out the box. In other words, you don't need to add JSTL to pom.xml nor to drop any JAR/TLD files in webapp. Solely the provided scoped Jakarta EE coordinate is sufficient:

<dependency>
    <groupId>jakarta.platform</groupId>
    <artifactId>jakarta.jakartaee-api</artifactId>
    <version><!-- 10.0.0, 9.1.0, 9.0.0, 8.0.0, etc depending on your server --></version>
    <scope>provided</scope>
</dependency>

Make sure web.xml version is right

Further you should also make sure that your web.xml is declared conform at least Servlet 2.4 and thus not as Servlet 2.3 or older. Otherwise EL expressions inside JSTL tags would in turn fail to work. Pick the highest version matching your target container and make sure that you don't have a <!DOCTYPE> anywhere in your web.xml as that would otherwise still trigger Servlet 2.3 modus. Here's a Servlet 6.0 (Tomcat 10.1.x) compatible example:

<?xml version="1.0" encoding="UTF-8"?>
<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">

    <!-- Config here. -->

</web-app>

And here's a Servlet 5.0 (Tomcat 10.0.x) compatible example:

<?xml version="1.0" encoding="UTF-8"?>
<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_5_0.xsd"
    version="5.0">

    <!-- Config here. -->

</web-app>

And here's a Servlet 4.0 (Tomcat 9) compatible example:

<?xml version="1.0" encoding="UTF-8"?>
<web-app
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
    version="4.0">

    <!-- Config here. -->

</web-app>

An answer for the year 2021

The question is still very popular, but all the answers are seriously outdated. All Java EE components were split off into various Jakarta projects and JSTL is no different. So here are the correct Maven dependencies as of today:

<dependency>
    <groupId>jakarta.servlet.jsp.jstl</groupId>
    <artifactId>jakarta.servlet.jsp.jstl-api</artifactId>
    <version>1.2.7</version>
</dependency>
<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>1.2.6</version>
</dependency>

Yes, the versions and groupIds do not match, but that's a quirk of the project's current state.

The most possible solutions for 2022

1 - Missing Libarires: download the library jstl/1.2 and Java Servlet API » 4.0.1

2 - Add these libraries to your project and also into the tomcat/lib folder.

3 - Add: <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> first line of the page.

4 - if you are using maven add the following into pom.xml file :

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>servlet-api</artifactId>
    <version>2.5</version>
    <scope>provided</scope>
</dependency>
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>

I have mentioned that the Maven dependency in the pom.xml is wrong. It should be

    <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

Just had similar problem in Eclipse fixed with:

rightclick on project->Properties->Deployment Assembly->add Maven Dependencies

something kicked it out before, while I was editing my pom.xml

I had all needed jar files, taglib uri and web.xml was ok

I had disabled MAVEN and Spring tools completely. And I had to add the following jar's for making my environment work right.

spring-aop-4.0.3.RELEASE.jar
spring-beans-4.0.3.RELEASE.jar (tough to find this fix, other org.springframework<3.versions> just did not work.
spring-context-4.0.3.RELEASE.jar
spring-core-4.0.3.RELEASE.jar
spring-expression-4.0.3.RELEASE.jar
spring-web-4.0.3.RELEASE.jar
spring-webmvc-4.0.3.RELEASE.jar
jstl-1.2.jar

The worst of all was jstl-api-1.2.jar and javax-servlet.jsp.jst-api-1.2.1.jar. They just did not work.

jstl-1.2.jar worked well.

If you use Spring boot, consider to remove server.tomcat.additional-tld-skip-patterns=*.jar from Application.properties if there is any

All of the answers in this question helped me but I thought I'd add some additional information for posterity.

It turned out that I had a test dependency on gwt-test-utils which brought in the gwt-dev package. Unfortunately gwt-dev contains a full copy of Jetty, JSP, JSTL, etc. which was ahead of the proper packages on the classpath. So even though I had proper dependencies on the JSTL 1.2 it would loading the 1.0 version internal to gwt-dev. Grumble.

The solution for me was to not run with test scope so I don't pick up the gwt-test-utils package at runtime. Removing the gwt-dev package from the classpath in some other manner would also have fixed the problem.

If using Tomcat 10:

Download

jakarta.servlet.jsp.jstl-2.0.0.jar

jakarta.servlet.jsp.jstl-api-2.0.0.jar

Place in /WEB-INF/lib folder.

Don't forget to restart Tomcat!

This workedfor me

    <groupId>jstl</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>

I had the same issue , I am using eclipse, just in case others experience the same issue:
In eclipse double click the tomcat server,
stop the server
untick the "server modules without publishing"
start the server.

How to install JSTL? The absolute uri: http://java.sun.com/jstl/core cannot be resolved

Resolved same problem in Netbeans 12.3 and Tomcat 9.0:

1.Write in pom.xml:

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

2.Add jstl-1.2.jar in project.

3.Install manually artifact(Choose jstl-1.2.jar - downloaded from the Internet )

2023 version Nothing else worked for me except adding the below to pom.xml: PS: I do realize that version 2.0.0 of jakarta.servlet.jsp.jstl contains some vulnerability, please use caution.

<!-- https://mvnrepository.com/artifact/jakarta.servlet.jsp.jstl/jakarta.servlet.jsp.jstl-api -->
        <dependency>
            <groupId>jakarta.servlet.jsp.jstl</groupId>
            <artifactId>jakarta.servlet.jsp.jstl-api</artifactId>
            <version>2.0.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.glassfish.web/jakarta.servlet.jsp.jstl -->
        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>jakarta.servlet.jsp.jstl</artifactId>
            <version>2.0.0</version>
        </dependency>

Resolved similar problem in IBM RAD 7.5 by selecting: