通过Jetty搭建一个简单的Servlet运行环境

最近在做一些简单的Servlet开发的时候,感觉每次调试的时候都要发布到tomcat上很麻烦,把程序共享给同事也很麻烦,需要帮他设置本地的tomcat环境. 在网上找了找其他的Servlet运行环境,发现用Jetty可以很方便的实现嵌入式Web container.这里我记录一下通过Jetty搭建简单Servlet运行环境的过程,希望对有同样需要的朋友有所帮助.

整个环境的代码可以在https://github.com/mcai4gl2/jettysetup找到. 代码包括了IntelliJ的项目文件,如果需要eclipse项目文件,请在下载代码后运行 mvn eclipse:eclipse 来生成eclipse项目文件. (当然, 请在本地安装Maven).

• 设置Maven Dependency:

  <dependencies>
          <!-- jetty -->
          <dependency>
              <groupId>org.eclipse.jetty</groupId>
              <artifactId>jetty-server</artifactId>
              <version>${jetty.version}</version>
          </dependency>
          <dependency>
              <groupId>org.eclipse.jetty</groupId>
              <artifactId>jetty-servlet</artifactId>
              <version>${jetty.version}</version>
          </dependency>
          <!-- spring -->
          <dependency>
              <groupId>org.springframework</groupId>
              <artifactId>spring-webmvc</artifactId>
              <version>${spring.version}</version>
          </dependency>
          <!-- log4j -->
          <dependency>
              <groupId>log4j</groupId>
              <artifactId>log4j</artifactId>
              <version>1.2.17</version>
          </dependency>
          <!-- utils -->
          <dependency>
              <groupId>org.apache.commons</groupId>
              <artifactId>commons-io</artifactId>
              <version>1.3.2</version>
          </dependency>
      </dependencies>

• 设置servlet-context.xml:

  <?xml version="1.0" encoding="UTF-8"?>
  <beans:beans xmlns="http://www.springframework.org/schema/mvc"
               xmlns:beans="http://www.springframework.org/schema/beans"
               xmlns:context="http://www.springframework.org/schema/context"
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xsi:schemaLocation="
  http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
  http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">
  
      <interceptors>
          <interceptor>
              <mapping path="/*"/>
              <beans:bean class="weblog.examples.jettysetup.LoggingInterceptor"/>
          </interceptor>
      </interceptors>
  
      <context:annotation-config/>
  
      <context:component-scan base-package="weblog.examples.jettysetup.serlvet"/>
  </beans:beans>

• 一个简单的Main Class:

  public static void main(String[] args) throws Exception {
          try {
              DOMConfigurator.configure(Thread.currentThread().getContextClassLoader().getResource("log4j.xml"));
  
              Server server = new Server();
  
              SelectChannelConnector connector = new SelectChannelConnector();
              connector.setPort(7411);
              server.setConnectors(new Connector[] {connector});
  
              DispatcherServlet servlet = new DispatcherServlet();
              servlet.setContextConfigLocation("classpath:servlet-context.xml");
  
              ServletContextHandler context = new ServletContextHandler();
              context.setContextPath("/");
              context.addServlet(new ServletHolder("baseServlet", servlet), "/");
  
              HandlerCollection handlers = new HandlerCollection();
              handlers.setHandlers(new Handler[] { context, new DefaultHandler()});
              server.setHandler(handlers);
  
              XmlWebApplicationContext wctx = new XmlWebApplicationContext();
              wctx.setConfigLocation("");
              wctx.setServletContext(servlet.getServletContext());
              wctx.refresh();
  
              context.setAttribute(XmlWebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, wctx);
              server.start();
  
              log.info("Jetty embedded server started");
  
              log.info("Press any key to stop");
              System.in.read();
              log.info("Stopping Server");
              server.stop();
              log.info("Server stopped");
  
          } catch (Exception ex) {
              log.error("Failed to run Jetty Server", ex);
              throw ex;
          }
      }

在JettyLauncher运行后,我们可以访问http://localhost:7411/ping来查看Jetty是否成功运行. http://localhost:7411/ping将运行以下Spring MVC Servlet:

@Controller
public class TestServlet {

    private static Logger log = Logger.getLogger(TestServlet.class);

    @RequestMapping(value="/ping", method = RequestMethod.GET)
    public void ping(HttpServletResponse response) throws IOException {
        log.info("ping page is called");
        IOUtils.write("Embedded Jetty Server is Up and Running", response.getOutputStream());
    }
}

通过Jetty,我们可以很容易的在本地运行和调试Servlet,而生成好的Servlet我们可以直接发布到Tomcat. 这样,我们可以简化Servlet的开发和调试.