早上好,我不知道如何解决该异常,我在 Eclipse 下使用 ApcheTomcat 7,每次运行我的 servlet 时都会抛出该异常,为了更清楚,这里是我的 servlet:
package servlets;
import java.util.*;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import dao.*;
@WebServlet("/AdminServlt")
public class AdminServlt extends HttpServlet {
private static final long serialVersionUID = 1L;
CarHome carDao;
public void init(ServletConfig config) throws ServletException{
carDao = new CarHome();
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
populateAdminView(request, response);
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
}
public void populateAdminView(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{
ArrayList productsList = (ArrayList) carDao.extractAdminAttributes();
HttpSession session = request.getSession(true);
session.setAttribute("product_list",productsList);
RequestDispatcher rd = request.getRequestDispatcher("Admin.jsp");
rd.forward(request, response);
}
}
这是CarHome.java
package dao;
import java.util.ArrayList;
import java.util.List;
import javax.naming.InitialContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.LockMode;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.*;
import entity.*;
public class CarHome {
private static final Log log = LogFactory.getLog(CarHome.class);
private final SessionFactory sessionFactory = getSessionFactory();
public List extractAdminAttributes() {
log.debug("Extracting car attributes for administrator view");
try {
ArrayList results = (ArrayList) sessionFactory
.getCurrentSession()
.createCriteria("pojo.Car")
.setProjection(
Projections.projectionList()
.add(Projections.property("carDesc"))
.add(Projections.property("price"))
.add(Projections.property("quantity")));
return results;
} catch (RuntimeException re) {
log.error("find by admin view failed");
throw re;
}
}
}
这是异常的堆栈跟踪
java.lang.ClassNotFoundException: org.hibernate.criterion.Projection
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1676)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1521)
servlets.AdminServlt.init(AdminServlt.java:31)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)