I created a j2ee web app and converted to maven project, but I have this error
javax.servlet.ServletException: java.lang.ClassNotFoundException: com.mysql.cj.jbdc.Driver.
I've tried all solutions : maven dependecy, paste the jar file manually in web app lib, paste the jar file manually in Tom cat lib , added the path on build path but still havin the same problem.
I am using Eclipse
Any help please thank a lot.
the conn class
public class DbCon {
private static Connection connection = null;
public static Connection getConnection() throws ClassNotFoundException, SQLException {
if(connection==null) {
Class.forName("com.mysql.cj.jbdc.Driver");
connection = DriverManager.getConnection("jbdc:mysql://localhost:3306/ecommerce_cart","root","");
System.out.print("connected");
}
return connection;
}
}
I call in index.jsp
<%# page import="cn.techtutorial.connection.DbCon" %>
<!DOCTYPE html>
<html>
<head>
<%# include file="includes/head.jsp" %>
<title>Shopping Cart Home</title>
</head>
<body>
<%# include file="includes/navbar.jsp" %>
<% out.print(DbCon.getConnection()); %>
<%# include file="includes/footer.jsp" %>
</body>
</html>
But it gives me this error:
javax.servlet.ServletException: java.lang.ClassNotFoundException: com.mysql.cj.jbdc.Driver.
Please help guys thanks
Related
I'm a beginner in spring programming. (i'm not good in english)
I have a problem that I can not get value from the controller.
My previous jsp worked fine, but I did not work with this project about a week then back to work, and i founded all jsp that I created after can not get value from the controller. But my previous jsp page worked fine.
I have seen on the same question and they said the error focus on version in web.xml but I dont have this error because the previous page jsp is still work fine.
Web.xml
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"
JSP file
<%# page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%#taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<%# page isELIgnored="false" %>
</head>
<body> <h1>${check}</h1> </body> </html>
Controller
#Controller
public class SingleController {
#RequestMapping(value="/single", method=RequestMethod.GET)
public ModelAndView single() {
ModelAndView mav = new ModelAndView();
mav.setViewName("single");
mav.addObject("check", "123");
return mav;
}
}
Current I have 1 bug when I run 1 project of Spring
1- Create class common: BlogMvcApplication.java
package blog;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class BlogMvcApplication {
public static void main(String[] args) {
SpringApplication.run(BlogMvcApplication.class, args);
}
}
2- Create class control: HomeController.java
package blog.controllers;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
#Controller
public class HomeController {
#RequestMapping("/")
public String index() {
return "index";
}
}
3- view: index.html
<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8" />
<title>Blog</title>
</head>
<body>
<h1>Welcome to Spring MVC</h1>
Now is: <b th:text="${execInfo.now.time}"></b>
</body>
</html>
Error when access http://localhost:8080 is :
2017-03-02 00:55:41.931 ERROR 1068 --- [nio-8080-exec-1] org.thymeleaf.TemplateEngine : [THYMELEAF][http-nio-8080-exec-1] Exception processing template "index": Error resolving template "index", template might not exist or might not be accessible by any of the configured Template Resolvers
2017-03-02 00:55:41.958 ERROR 1068 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.thymeleaf.exceptions.TemplateInputException: Error resolving template "index", template might not exist or might not be accessible by any of the configured Template Resolvers] with root cause
org.thymeleaf.exceptions.TemplateInputException: Error resolving template "index", template might not exist or might not be accessible by any of the configured Template Resolvers
at org.thymeleaf.TemplateRepository.getTemplate(TemplateRepository.java:246) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1104) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1060) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1011) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
I think error because duplicate port 8080 when start
Please helpme fix bug this
Thanks!
I don't think this error cause by duplication on port. If it is the issue then you cannot start your application and will see message like this: ".... port 8080 failed to start".
It seen like your index.html cannot be found at default location:/src/main/resources/templates/index.html when thymeleaf engine try to parse your requested template.
Hope it helps.
I am new to Spring MVC. I have basic Rest Controller and JSP. I want to be able to access the URL in the request mapping annotations from the JSP. I noticed that mvcUrl in Spring MVC 4.1 allows you to do that. But I run into an error when I try this:
When I open localhost/test.jsp. I see this in the browser:
org.apache.jasper.JasperException: javax.el.ELException: Problems calling function 's:mvcUrl'
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:556)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:477)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
.....
java.lang.IllegalArgumentException: Cannot lookup handler method mappings without WebApplicationContext
org.springframework.util.Assert.notNull(Assert.java:115)
org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder.getRequestMappingInfoHandlerMapping(MvcUriComponentsBuilder.java:521)
org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder.fromMappingName(MvcUriComponentsBuilder.java:330)
org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder.fromMappingName(MvcUriComponentsBuilder.java:313)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
....
Here is some sample code that I used
#RestController
#RequestMapping("/foo")
public class FooRestController {
#RequestMapping(value = "/hello", method = RequestMethod.GET)
public String hello() {
return "hello";
}
}
JSP File - test.jsp
<%# page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%# taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%# taglib uri="http://www.springframework.org/tags" prefix="s" %>
Link to Hello
What could be setup wrong?
When I hit localhost/foo/hello I do get back a json string "hello". Doesn't that mean the dispatcher servlet is working fine and the WebApplicationContext is actually setup properly?
The problem here is: you only defined controller handler for /foo/hello, but not for /test.jsp . Try adding a new controller:
#Controller
#RequestMapping("/")
public class GeneralController {
...
#RequestMapping(value = "/test.jsp", method = RequestMethod.GET)
public String hello() {
return "test"; // put the view name here. You won't need ".jsp" because it would be automatically added by the view resolver in the configuration below
}
}
and make sure similar code exists in your configuration, so that the system know where to look for your view
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/[Your_JSP_FOLDER]"/>
<property name="suffix" value=".jsp"/>
</bean>
This not a problem with your configuration file as you are using
#RestController annotaion in your controller which is a convenience annotation that is itself annotated with #Controller and #ResponseBody . as you may know annotating your class with #ResponseBody will return you back the json response from the method of the coltroller which is the expected behavior in this case.
If you want to get the jsp file what you should have used is
1.use #Controller instead of #RestController
2.Assuming you have configured view resolver with prefix and suffix for jsp page and return test string from the method because your jsp file name says it's name is test .
Hope this answer your question.
I don't think this is a configuration issue we have also faced similar kind of issues the only solution was to use modelandview instead of returning the view as string in the controller
I'm following a tutorial about spring and I'm supposed to set a variable in a controller in order to be printed within the jsp rendering the request. The code is as follows:
#Controller
public class HelloController {
#RequestMapping(value="/hello.htm")
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String now = (new Date()).toString();
return new ModelAndView("WEB-INF/views/hello.jsp", "now", now);
}
}
Then, the hello.jsp code is as follows:
<%# page session="true"%>
<%# taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%# taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
<html>
<body>
<p>Greetings, it is now <c:out value="${now}" /></p>
</body>
</html>
I am expected to get an html showing this:
Greetings, it is now Mon Fri Dec 06 00:39:35 CET 2013
But all I get is:
Greetings, it is now ${now}
I've checked everything twice (or even more!) but everything seems to be as the tutorial says but there must be something missing, I hope...
What's wrong with my code?
This is an E xpression L anguage issue. Your ${} is not being resolved. This can happen for a number of reasons. One, and the most likely, is that your web.xml is declaring Servlet 2.3 and under. You'll have to specify 2.4+. Now, obviously, your Servlet container must also support that higher version.
Change this - the pad a library is bad:
<!-- %# taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>-->
<%# taglib prefix="c" uri="http://java.sun.com/jstl/core" %>
<%# taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
I tried to run the following lines.
<%=application.getInitParameter("tagline")%>
<br />
<%=config.getInitParameter("admincontact")%>
${initParam.tagline}
<br />
${pageContext.servletConfig.initParameter("admincontact")}
And my web.xml is
<servlet>
<jsp-file>/index.jsp</jsp-file>
<init-param>
<param-name>admincontact</param-name>
<param-value>8939302763</param-value>
</init-param>
</servlet>
<context-param>
<param-name>tagline</param-name>
<param-value>Each one Plant one</param-value>
I get a exception at
${pageContext.servletConfig.initParameter("admincontact")}
and null value for
<%=config.getInitParameter("admincontact")%>.
Regards,
John
There is an FAQ on JavaRanch about this.
It states the following;
How to access servlet init parameters using EL?
You cannot use the following syntax to access servlet init parameters:
${pageContext.servletConfig.initParameter.name}
You cannot get Servlet init parameters using this technique. The
getInitParameter(java.lang.String name) does not fit in this case,
because it requires some arguments.
According to the JavaBean spec, the property has getter & setter
methods in the form
public type1 getXXX() -- WITH NO ARGUMENTS.
public void setXXX(type1)
Now consider the pageContext as bean Object. The
PageContext class has methods like getServletConfig(), getRequest(),
getSession() etc. You can access these like pageContext.page,
pageContext.request etc in EL.
ServletContext object has a couple of methods like getMajorVersion(),
getMinorVersion() with no args. so we can access these methods
treating it as properties to sevletContext bean as
pageContext.servletContext.majorVersion and
pageContext.servletContext.minorVersion.
If you want to access Servlet init parameters using EL, then it is
better to create a Map of the init parameters for the servlet and
place it in the request as a scoped variable -- let's say
initParameters. You would then be able to obtain any param by name
with ${requestScope.initParameters.name}.
NOTE:
We can access context init parameters with ${initParam.name}
In addition to Mr Moose's answer, I have found this solution that uses EL defining a custom tag.
It worked in my case.
Here the link
Basically you have to create a Java class like this:
package example.customTags;
import javax.servlet.jsp.JspPage;
public class MyFunctions {
public static String getJspInitParameter(JspPage page, String param){
return page.getServletConfig().getInitParameter(param);
}
}
Create a tld file like this (my filepath is WEB-INF/myTags/customTags.tld):
<taglib>
<tlib-version>1.0</tlib-version>
<jsp-version>2.0</jsp-version>
<short-name>Functions</short-name>
<function>
<name>getJspInitParameter</name>
<function-class>example.customTags.MyFunctions</function-class>
<function-signature>
java.lang.String getJspInitParameter(javax.servlet.jsp.JspPage, java.lang.String)
</function-signature>
</function>
</taglib>
And use it in your JSP like this:
<%# page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%# taglib prefix="my" uri="../WEB-INF/myTags/customTags.tld"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Example</title>
</head>
<body>
<c:out value="${my:getJspInitParameter(pageContext.page, 'admincontact')}"/>
</body>
</html>