在Jetty中部署简单的Web应用程序时遇到问题

Question

I am using Jetty to write a simple server.

SimpleServer.java:

public class SimpleServer {

    public static void main(String[] args) throws Exception {
        Server server = new Server(8080);
        server.setHandler(new ServerHandler());
        server.start();
        server.join();
    }   

}

ServerHandler.java:

public class ServerHandler extends AbstractHandler {

    public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

        response.setContentType("text/html; charset=utf-8");
        response.setStatus(HttpServletResponse.SC_OK);
        baseRequest.setHandled(true);
        response.getWriter().println("<h1>Hello World</h1>");
    }
}

I use maven to package the files up into a war file and then throw them in the jetty/webapps directory. I have the war file named root.war, so that means the context is at localhost:8080/. But when I access it, I get the following error in the browser:

HTTP ERROR 503

Problem accessing /. Reason:

    Service Unavailable

In the console, I get a java.lang.reflect.InvocationTargetException . This project works and runs in IntelliJ. It's only when I put it in the jetty/webapps folder that I get errors.

Answer 1

Your example codebase is written using the Jetty Handler API.

A WAR file expects the Servlet API , not the Jetty Handler API.

If you want to continue using the Jetty Handler API, then you'll be staying with embedded-jetty and doing everything without a WAR file.

If you want a WAR file, then you'll have to not use the Jetty Handler API.

Migrate your code to using the Servlet API, and add a reference to it in your Web Descriptor ( WEB-INF/web.xml ). That will produce a proper WAR file that can be deployed.

public class ServerServlet extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    {
        response.setContentType("text/html; charset=utf-8");
        response.setStatus(HttpServletResponse.SC_OK);
        response.getWriter().println("<h1>Hello World</h1>");
    }
}

Note: You can optionally, you can use the Servlet API Annotations instead of the WEB-INF/web.xml , but know that you'll want your ${jetty.base} instance directory configured to have the annotations module enabled.