Robin Hughes [http://community.jboss.org/people/rhinmass] created the discussion "Struggling with injecting singleton in 6.0" To view the discussion, visit: http://community.jboss.org/message/597183#597183 -------------------------------------------------------------- Hello, I am having trouble figuring out how to inject a singleton into another class - in this case a servlet.  My singleton looks like this: package com.robin.ejb import javax.ejb.Singleton; import javax.ejb.Startup; @Singleton @Startup public class HelloWorld {     public HelloWorld()     {         System.out.println("constructing HelloWorld");     }       public String sayHello() {         return "Hello World !!!";     } } My servlet looks like this: import ... import com.robin.ejb.HelloWorld; @WebServlet(name="helloServlet", urlPatterns={"/hello"},         initParams={ @WebInitParam(name="nameParam", value="world")}) public class HelloServlet extends HttpServlet {     private static final long serialVersionUID = 1L;     @Inject     private HelloWorld hw;     @Override     protected void doGet(HttpServletRequest request, HttpServletResponse response)             throws ServletException, IOException {         PrintWriter out = response.getWriter();         String nameParam = request.getParameter("nameParam");         if (nameParam == null)             nameParam = getServletConfig().getInitParameter("nameParam");         out.println("hello " + nameParam + " " + hw.sayHello());         out.flush();         out.close();     } } When I run this in JBoss AS 6.0.0.Final I get the following errors: 2011-04-01 10:23:43,299 ERROR [org.jboss.kernel.plugins.dependency.AbstractKernelController] (Thread-2) Error installing to Start: name=vfs:///C:/jboss/jboss-6.0.0.Final/server/rbh/deploy/myapp-0.0.1.ear_WeldBootstrapBean state=Create: org.jboss.weld.exceptions.DeploymentException: WELD-001409 Ambiguous dependencies for type [HelloWorld] with qualifiers [@Default] at injection point [[field] @Inject private com.robin.webapp.HelloServlet.hw]. Possible dependencies [[Session bean [class com.robin.ejb.HelloWorld with qualifiers [@Any @Default]; local interfaces are [HelloWorld], Session bean [class com.robin.ejb.HelloWorld with qualifiers [@Any @Default]; local interfaces are [HelloWorld]]]     at org.jboss.weld.bootstrap.Validator.validateInjectionPoint(Validator.java:309) [:6.0.0.Final]     at org.jboss.weld.bootstrap.Validator.validateBean(Validator.java:139) [:6.0.0.Final]     at org.jboss.weld.bootstrap.Validator.validateRIBean(Validator.java:162) [:6.0.0.Final]     at org.jboss.weld.bootstrap.Validator.validateBeans(Validator.java:377) [:6.0.0.Final]     at org.jboss.weld.bootstrap.Validator.validateDeployment(Validator.java:363) [:6.0.0.Final]     at org.jboss.weld.bootstrap.WeldBootstrap.validateBeans(WeldBootstrap.java:388) [:6.0.0.Final] -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/597183#597183] Start a new discussion in Beginner's Corner at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]