Java Guice with servlets Exception in thread "main" java.lang.NoClassDefFoundError: com/google/inject/internal/util/$Preconditions

Question

I'm trying to configure Guice with Google App Engine, but I get this problem when I start the server (with "gradle appengineRun"):

Exception in thread "main" java.lang.NoClassDefFoundError: com/google/inject/internal/util/$Preconditions
    at com.google.inject.servlet.ServletModule.configure(ServletModule.java:44)
    at com.google.inject.AbstractModule.configure(AbstractModule.java:62)
    at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:340)
    at com.google.inject.spi.Elements.getElements(Elements.java:110)
    at com.google.inject.internal.InjectorShell$Builder.build(InjectorShell.java:138)
    at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:104)
    at com.google.inject.Guice.createInjector(Guice.java:96)
    at com.google.inject.Guice.createInjector(Guice.java:73)
    at com.google.inject.Guice.createInjector(Guice.java:62)
    at MyGuiceServletConfig.getInjector(MyGuiceServletConfig.java:17)
    at com.google.inject.servlet.GuiceServletContextListener.contextInitialized(GuiceServletContextListener.java:45)
    at org.eclipse.jetty.server.handler.ContextHandler.callContextInitialized(ContextHandler.java:843)
    at org.eclipse.jetty.servlet.ServletContextHandler.callContextInitialized(ServletContextHandler.java:533)
    at org.eclipse.jetty.server.handler.ContextHandler.startContext(ContextHandler.java:816)
    at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:345)
    at org.eclipse.jetty.webapp.WebAppContext.startWebapp(WebAppContext.java:1406)
    at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1368)
    at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:778)
    at org.eclipse.jetty.servlet.ServletContextHandler.doStart(ServletContextHandler.java:262)
    at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:522)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:131)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:105)
    at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:61)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:131)
    at org.eclipse.jetty.server.Server.start(Server.java:422)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:105)
    at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:61)
    at org.eclipse.jetty.server.Server.doStart(Server.java:389)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at com.google.appengine.tools.development.jetty9.JettyContainerService.startContainer(JettyContainerService.java:346)
    at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:284)
    at com.google.appengine.tools.development.AutomaticInstanceHolder.startUp(AutomaticInstanceHolder.java:26)
    at com.google.appengine.tools.development.AbstractModule.startup(AbstractModule.java:87)
    at com.google.appengine.tools.development.Modules.startup(Modules.java:105)
    at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:274)
    at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
    at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:219)
    at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:217)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:217)
    at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:368)
    at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:47)
    at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:223)
    at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:214)
Caused by: java.lang.ClassNotFoundException: com.google.inject.internal.util.$Preconditions
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(IsolatedAppClassLoader.java:196)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 46 more

Project structure:

ProjectStructure

The server and the Infrastructure part contains only some DAO and Factory elements

web.xml:

<?xml version="1.0" encoding="utf-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
     version="2.5">
<!--<servlet>-->
    <!--<servlet-name>hello</servlet-name>-->
    <!--<servlet-class>Main</servlet-class>-->
<!--&lt;!&ndash;</servlet>&ndash;&gt;-->
<!--<servlet-mapping>-->
    <!--<servlet-name>hello</servlet-name>-->
    <!--<url-pattern>/data</url-pattern>-->
<!--</servlet-mapping>-->
<listener>
    <listener-class>
        MyContextListener
    </listener-class>

</listener>
<listener>
    <listener-class>MyGuiceServletConfig</listener-class>
</listener>
</web-app>

The MyContextListener is supposed to load up the database with some initial data, and that works correctly, but I don't know if I can use it with MyGuiceServletConfig.

MyGuiceServletConfig.java:

import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Provides;
import com.google.inject.name.Named;
import com.google.inject.name.Names;
import com.google.inject.servlet.GuiceServletContextListener;
import com.google.inject.servlet.RequestScoped;
import com.google.inject.servlet.ServletModule;
import edu.ubb.cs.idde.DAO.EmployeeDAOHibernatePersistence;
import edu.ubb.cs.idde.DAO.EmployeesDAO;
import edu.ubb.cs.idde.Employees.Employee;

public class MyGuiceServletConfig extends GuiceServletContextListener {

@Override
protected Injector getInjector() {
    return Guice.createInjector(new ServletModule(){

        @Override
        protected void configureServlets(){
            serve("/data").with(Main.class);
            bind(EmployeesDAO.class).annotatedWith(Names.named("HibernatePersistence")).to(EmployeeDAOHibernatePersistence.class);
        }

    });

}

}

Main.java:

import com.google.gson.Gson;
import com.google.inject.Inject;
import com.google.inject.name.Named;
import edu.ubb.cs.idde.DAO.EmployeeDAOHibernatePersistence;
import edu.ubb.cs.idde.DAO.EmployeesDAO;
import edu.ubb.cs.idde.DAO.EmployeesDAOHibernate;
import edu.ubb.cs.idde.Employees.Employee;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.inject.Singleton;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Singleton
public class Main extends HttpServlet {
EmployeesDAO empl;

@Inject
Main(EmployeesDAO employeesDAO)
{
    this.empl = new EmployeeDAOHibernatePersistence();
}


@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    PrintWriter out = resp.getWriter();
    Gson gson = new Gson();
    List<Object> list = empl.readAllEmployees();
    out.println(gson.toJson(list));
}

@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) 
throws ServletException, IOException {
    PrintWriter out = resp.getWriter();
    Gson gson = new Gson();
//        int ID = 
Integer.parseInt(String.valueOf(req.getParameterValues("ID")));
    String first = String.valueOf(req.getParameterValues("First"));
    String last = String.valueOf(req.getParameterValues("Last"));
    int age = 
Integer.parseInt(String.valueOf(req.getParameterValues("Age")));
    empl.createEmployee(new Employee(first,last,age));
    out.println("OK");
}

@Override
protected void doPut(HttpServletRequest req, HttpServletResponse resp) 
throws ServletException, IOException {
    PrintWriter out = resp.getWriter();
    Gson gson = new Gson();
    int ID = Integer.parseInt(String.valueOf(req.getParameterValues("ID")));
    String first = String.valueOf(req.getParameterValues("First"));
    String last = String.valueOf(req.getParameterValues("Last"));
    int age = 
Integer.parseInt(String.valueOf(req.getParameterValues("Last")));
    empl.updateEmployee(new Employee(first,last,age));
    out.println("OK");
}

@Override
protected void doDelete(HttpServletRequest req, HttpServletResponse resp) 
throws ServletException, IOException {
    PrintWriter out = resp.getWriter();
    Gson gson = new Gson();
    int ID = Integer.parseInt(String.valueOf(req.getParameterValues("ID")));
    String first = String.valueOf(req.getParameterValues("First"));
    String last = String.valueOf(req.getParameterValues("Last"));
    int age = 
Integer.parseInt(String.valueOf(req.getParameterValues("Last")));
    empl.deleteEmployee(new Employee(first,last,age));
    out.println("OK");
}

}

score 0 · Answer 1 · answered Feb 13 '18 at 11:18

Based on other similar situations, it seems you are using an outdated version of Guice, or at least an extension of Guice which is not version-consistent with the rest of the library.

Make sure you use the same version for the Guice library and its extensions (the most recent one is 4.1).

Anyway, whenever you deploy the app, follow the steps described here.

Java Guice with servlets Exception in thread "main" java.lang.NoClassDefFoundError: com/google/inject/internal/util/$Preconditions

1 Answers1