有没有办法在Undertow中使用Servlet API？

Question

我刚刚发现了Undertow是如何工作的,我对它的api感到惊讶:

Undertow server = Undertow.builder()
                .addHttpListener(8080, "localhost")
                .setHandler(new HttpHandler() {
                    @Override
                    public void handleRequest(final HttpServerExchange exchange) throws Exception {
                        exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, "text/plain");
                        exchange.getResponseSender().send("Hello World");
                    }
                }).build();
        server.start();

有没有办法以某种方式使用更方便的servlet api？

Undertow server = Undertow.builder()
                .addHttpListener(8080, "localhost")
                .setHandler(new HttpHandler() {
                    @Override
                    public void handleRequest(final HttpServletRequest request, final HttpServletResponse response) throws Exception {
                        // ...
                    }
                }).build();
        server.start();

我想要实现的是替换当前使用的Undertow使用servlet api的Jetty容器,但是在阅读了文档和源代码后,我似乎找不到这样做的方法.我没有使用.war文件只是一个嵌入式Jetty.有人有指针吗？

Answer 1

它在创建Servlet部署一节中有介绍.这是一个基于提供的文档的MCVE,你有正确的依赖关系,以及Servlet API.

package com.stackoverflow.q35269763;

import io.undertow.Handlers;
import io.undertow.Undertow;
import io.undertow.server.handlers.PathHandler;
import io.undertow.servlet.Servlets;
import io.undertow.servlet.api.DeploymentInfo;
import io.undertow.servlet.api.DeploymentManager;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class Test {

    public static void main(String... args) throws Exception {
        DeploymentInfo servletBuilder = Servlets.deployment().setClassLoader(Test.class.getClassLoader())
            .setDeploymentName("myapp").setContextPath("/myapp")
            .addServlets(Servlets.servlet("myservlet",
                new HttpServlet() {
                    @Override
                    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
                        response.getWriter().write("Hello World!");
                    }
                }.getClass()).addMapping("/myservlet"));
        DeploymentManager manager = Servlets.defaultContainer().addDeployment(servletBuilder);
        manager.deploy();
        PathHandler path = Handlers.path(Handlers.redirect("/myapp")).addPrefixPath("/myapp", manager.start());
        Undertow server = Undertow.builder().addHttpListener(8888, "localhost").setHandler(path).build();
        server.start();
    }

}

在copy'n'paste'n'running上面的代码之后,当你在你最喜欢的webbrowser中打开http:// localhost:8888/myapp/myservlet时,你会看到

你好,世界!