使用Maven Jetty插件

尽管很长一段时间以来我一直在使用Maven，但直到最近我才使用过Jetty插件。为了能够测试REST客户端，我创建了一个Servlet，向我显示了所有传入的参数和带有传入请求的标头。为了在容器中运行servlet，我决定尝试使用Maven Jetty插件。所以首先我使用特定的Maven原型创建一个Web应用程序：

mvn archetype:generate -DgroupId=net.pascalalma -DartifactId=rest-service -Dversion=1.0.0-SNAPSHOT -DarchetypeArtifactId=maven-archetype-webapp

这将导致完整的项目和以下日志记录：

[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] >>> maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom >>>
[INFO] 
[INFO] <<< maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom <<<
[INFO] 
[INFO] --- maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
Downloading: http://artifactory.redstream.nl/repo/org/apache/maven/archetypes/maven-archetype-webapp/1.0/maven-archetype-webapp-1.0.jar
Downloaded: http://artifactory.redstream.nl/repo/org/apache/maven/archetypes/maven-archetype-webapp/1.0/maven-archetype-webapp-1.0.jar (4 KB at 5.2 KB/sec)
Downloading: http://artifactory.redstream.nl/repo/org/apache/maven/archetypes/maven-archetype-webapp/1.0/maven-archetype-webapp-1.0.pom
Downloaded: http://artifactory.redstream.nl/repo/org/apache/maven/archetypes/maven-archetype-webapp/1.0/maven-archetype-webapp-1.0.pom (533 B at 1.1 KB/sec)
[INFO] Using property: groupId = net.pascalalma
[INFO] Using property: artifactId = rest-service
[INFO] Using property: version = 1.0.0-SNAPSHOT
[INFO] Using property: package = net.pascalalma
Confirm properties configuration:
groupId: net.pascalalma
artifactId: rest-service
version: 1.0.0-SNAPSHOT
package: net.pascalalmaY: : Y
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Old (1.x) Archetype: maven-archetype-webapp:1.0
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: net.pascalalma
[INFO] Parameter: packageName, Value: net.pascalalma
[INFO] Parameter: package, Value: net.pascalalma
[INFO] Parameter: artifactId, Value: rest-service
[INFO] Parameter: basedir, Value: /Users/pascal/projects
[INFO] Parameter: version, Value: 1.0.0-SNAPSHOT
[INFO] project created from Old (1.x) Archetype in dir: /Users/pascal/projects/rest-service
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 13.057s
[INFO] Finished at: Sun Feb 03 17:13:33 CET 2013
[INFO] Final Memory: 7M/81M
[INFO] ------------------------------------------------------------------------
MacBook-Air-van-Pascal:projects pascal$

接下来，我将servlet代码添加到项目中：

package net.pascalalma.servlets;import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/**** @author pascal*/
public class TestRestServlet extends HttpServlet {public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {PrintWriter out = response.getWriter();out.println('GET method called');out.println('parameters:\n ' + parameters(request));out.println('headers:\n ' + headers(request));}public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {PrintWriter out = response.getWriter();out.println('POST method called');out.println('parameters: ' + parameters(request));out.println('headers: ' + headers(request));}public void doDelete(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {PrintWriter out = response.getWriter();out.println('Delete method called');}private String parameters(HttpServletRequest request) {StringBuilder builder = new StringBuilder();for (Enumeration e = request.getParameterNames(); e.hasMoreElements();) {String name = (String) e.nextElement();builder.append('|' + name + '->' + request.getParameter(name)+'\n');}return builder.toString();}private String headers(HttpServletRequest request) {StringBuilder builder = new StringBuilder();for (Enumeration e = request.getHeaderNames(); e.hasMoreElements();) {String name = (String) e.nextElement();builder.append('|' + name + '->' + request.getHeader(name)+'\n');}return builder.toString();}
}

并在“ web.xml”中配置servlet。顺便说一下，生成的“ web.xml”无法显示在我的Netbeans版本（v7.2.1）中。我收到消息：

Web应用程序版本不受支持。将web.xml升级到2.4或更高版本，或使用以前的NetBeans版本

为了解决这个问题，我修改了web.xml，使其从以下命名空间声明开始：

<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' id='WebApp_ID' version='2.5'>

接下来，将servlet添加到修改后的“ web.xml”中：

<?xml version='1.0' encoding='UTF-8'?>
...<display-name>Archetype Created Web Application</display-name><servlet><servlet-name>TestRestServlet</servlet-name><servlet-class>net.pascalalma.servlets.TestRestServlet</servlet-class></servlet><servlet-mapping><servlet-name>TestRestServlet</servlet-name><url-pattern>/TestRestServlet</url-pattern></servlet-mapping>
...

现在一切准备就绪，可以测试servlet。正如我之前所说的，我将为此使用Jetty插件。要将插件添加到项目中，只需将以下内容放入“ pom.xml”中：

<plugins><plugin><groupId>org.mortbay.jetty</groupId><artifactId>jetty-maven-plugin</artifactId><configuration><scanIntervalSeconds>10</scanIntervalSeconds><contextPath>/</contextPath><scanIntervalSeconds>10</scanIntervalSeconds><stopKey>STOP</stopKey><stopPort>8005</stopPort><port>8080</port></configuration></plugin>
</plugins>

现在，我可以在终端中运行命令“ mvn jetty：run”，以使容器运行servlet。日志应该以以下内容结尾：

....
2013-02-19 09:54:53.044:INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:8080
[INFO] Started Jetty Server
[INFO] Starting scanner at interval of 10 seconds.</code>

现在，如果您打开浏览器并转到该URL'http：// localhost：8080 / TestRestServlet？bla = true＆＃8217 ; 您将看到servlet的运行并输出到浏览器：

GET method called
parameters:
|bla->true

headers:
|DNT->1
|Host->localhost:8080
|Accept->text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
|Accept-Charset->ISO-8859-1,utf-8;q=0.7,*;q=0.3
|Accept-Language->en-US,en;q=0.8
|User-Agent->Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_5) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.57 Safari/537.17
|Connection->keep-alive
|Cache-Control->max-age=0
|Accept-Encoding->gzip,deflate,sdch

注意事项：如您所见，在插件配置中，为方便起见，我添加了一些额外的参数。因此，容器将每隔10秒检查一次servlet中的更改，因此我不必在每次更改servlet之后重新启动Jetty容器。要停止容器，您现在可以在另一个终端会话中输入命令'mvn jetty：stop -DstopPort = 8005 -DstopKey = STOP'。顺便说一句，请确保将插件命名为“ jetty-maven-plugin”，而不是“ maven-jetty-plugin”，因为那样您将使用该插件的旧版本，而该插件不会使用配置参数（是的，非常令我感到困惑和沮丧）。

参考：在The Pragmatic Integrator博客上使用我们JCG合作伙伴 Pascal Alma的Maven Jetty插件。