Windows Server 2008 R2, 64 Апач Мавен 2.2.1 Версия Java: 1.6.0_26 JAVA_HOME: C:\Program Files\Java\jdk1.6.0_26 Томкэт 7.0 Компиляция проекта с Java 1.6
Я пытаюсь использовать плагин tomcat7-maven-plugin для запуска сервера разработки tomcat, используя цель tomcat7:run. Когда я пытаюсь найти index.jsp для сервера, я получаю:
HTTP Status 500 - java.lang.LinkageError: loader constraint violation: loader (instance of org/apache/jasper/servlet/JasperLoader) previously initiated loading for a different type with name "javax/servlet/http/HttpServletRequest"
type Exception report
message java.lang.LinkageError: loader constraint violation: loader (instance of org/apache/jasper/servlet/JasperLoader) previously initiated loading for a different type with name "javax/servlet/http/HttpServletRequest"
description The server encountered an internal error (java.lang.LinkageError: loader constraint violation: loader (instance of org/apache/jasper/servlet/JasperLoader) previously initiated loading for a different type with name "javax/servlet/http/HttpServletRequest") that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: java.lang.LinkageError: loader constraint violation: loader (instance of org/apache/jasper/servlet/JasperLoader) previously initiated loading for a different type with name "javax/servlet/http/HttpServletRequest"
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:343)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
root cause
java.lang.LinkageError: loader constraint violation: loader (instance of org/apache/jasper/servlet/JasperLoader) previously initiated loading for a different type with name "javax/servlet/http/HttpServletRequest"
java.lang.Class.getDeclaredMethods0(Native Method)
java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
java.lang.Class.getDeclaredMethods(Class.java:1791)
org.apache.catalina.util.Introspection.getDeclaredMethods(Introspection.java:108)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:172)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
Я успешно использовал tomcat7:deploy для развертывания того же кода в локальном экземпляре службы tomcat Windows. Когда я обращаюсь к локальному экземпляру сервера, ошибок нет.
Мой код зависит от javax.servlet.http.HttpServlet через эту зависимость maven:
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
Учитывая ошибку, которую я получаю, я почти уверен, что для этой зависимости существует конфликт загрузки классов. Чего я не могу понять, так это как/почему/где возник конфликт; то есть, где конфликтующие банки, и как/почему это происходит, когда я пытаюсь запустить с помощью tomcat7: run, но не когда я запускаю «автономно», используя мой локальный экземпляр tomcat.
pom:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.moring.gloak</groupId>
<artifactId>gloak-registration</artifactId>
<packaging>war</packaging>
<version>1.0.0-SNAPSHOT</version>
<name>gloak-registration Maven Webapp</name>
<build>
<finalName>gloak-registration</finalName>
<plugins>
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.0-SNAPSHOT</version>
<configuration>
<server>local_tomcat</server>
<url>http://localhost:9280/manager/text</url>
<update>true</update>
<port>9280</port>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.5.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>people.apache.snapshots</id>
<url>http://repository.apache.org/content/groups/snapshots-group/</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
</dependencies>
</project>
проект web.xml
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<servlet>
<servlet-name>registrationServlet</servlet-name>
<servlet-class>com.moring.gloak.web.register.RegistrationServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>registrationServlet</servlet-name>
<url-pattern>/register</url-pattern>
</servlet-mapping>
</web-app>
объявление веб-приложения tomcat web.xml из maven target dir:
<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_3_0.xsd"
version="3.0">
фактический код сервлета:
package com.moring.gloak.web.register;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
public final class RegistrationServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.getRequestDispatcher("index.jsp").forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
Map<String, String> messages = new HashMap<String, String>();
request.setAttribute("messages", messages);
// Get and validate name.
String serviceName = request.getParameter("serviceName");
if (serviceName == null || serviceName.trim().isEmpty()) {
messages.put("name", "Please enter service name");
} else if (!serviceName.matches("\\p{Alnum}+")) {
messages.put("name", "Please enter alphanumeric characters only");
}
if (messages.isEmpty()) {
messages.put("success", String.format("Service name is %s", serviceName));
}
request.getRequestDispatcher("index.jsp").forward(request, response);
}
}