使用Jetty作为开发容器（非部署容器）

1. 说明：依旧使用tomcat作为容器，Jetty在这里只作为开发时测试方便，所以采取工具类形式，而非下载Jetty容器包配置方式。

2. 为什么要用Jetty？

此处用Jetty只是方便测试，运行个main方法即可启动Jetty容器，然后就可以调用接口和访问jsp等页面。无需启动tomcat，个人认为Jetty启动速度远快于tomcat。所以方便测试，更改代码只需要重新运行main方法即可。（Jetty自带热部署）

3. 如何使用？

• pom.xml定义如下

      
          org.eclipse.jetty.aggregate
          jetty-all-server
          8.1.18.v20150929
      
      
          org.eclipse.jetty
          jetty-jsp
          8.1.18.v20150929
      

• 工具类

package test.bshf.clinic.util;

import org.eclipse.jetty.jmx.MBeanContainer;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.util.Scanner;
import org.eclipse.jetty.webapp.WebAppContext;

import javax.management.MBeanServer;
import java.io.File;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.net.DatagramSocket;
import java.net.ServerSocket;
import java.util.ArrayList;
import java.util.List;


public class JettyServerStarter {
    private int           port;
    private String        context;
    private String        webappPath;
    private int           scanIntervalSeconds;
    private boolean       jmxEnabled;
    private Server        server;
    private WebAppContext webapp;

    public JettyServerStarter(String webappPath, int port, String context) {
        this(webappPath, port, context, 0, false);
    }

    public JettyServerStarter(String webappPath, int port, String context, int scanIntervalSeconds, boolean jmxEnabled) {
        this.webappPath = webappPath;
        this.port = port;
        this.context = context;
        this.scanIntervalSeconds = scanIntervalSeconds;
        this.jmxEnabled = jmxEnabled;
        validateConfig();
    }

    private void validateConfig() {
        if (port < 0 || port > 65536) {
            throw new IllegalArgumentException("Invalid port of web server: " + port);
        }
        if (context == null) {
            throw new IllegalStateException("Invalid context of web server: " + context);
        }
        if (webappPath == null) {
            throw new IllegalStateException("Invalid context of web server: " + webappPath);
        }
    }

    public void start() {
        if (server == null || server.isStopped()) {
            try {
                doStart();
            } catch (Throwable e) {
                e.printStackTrace();
                System.err.println("System.exit() ......");
                System.exit(1);
            }
        } else {
            throw new RuntimeException("Jetty Server already started.");
        }
    }

    private void doStart() throws Throwable {
        if (!portAvailable(port)) {
            throw new IllegalStateException("port: " + port + " already in use!");
        }

        System.setProperty("org.eclipse.jetty.util.URI.charset", "UTF-8");
        System.setProperty("org.eclipse.jetty.util.log.class", "org.eclipse.jetty.util.log.Slf4jLog");
        System.setProperty("org.eclipse.jetty.server.Request.maxFormContentSize", "20000000");

        server = new Server(port);
        server.setHandler(getHandler());

        if (jmxEnabled) {
            MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
            MBeanContainer mBeanContainer = new MBeanContainer(mBeanServer);
            server.addBean(mBeanContainer);
        }

        if (scanIntervalSeconds > 0) {
            startFileWatchScanner();
        }

        long ts = System.currentTimeMillis();
        server.start();

        ts = System.currentTimeMillis() - ts;
        System.err.println("Jetty Server started: " + String.format("%.2f sec", ts / 1000d));

        server.join();
    }
    
    
    protected Handler getHandler(){
        webapp = new WebAppContext(webappPath, context);
        return webapp;
    }

    private void startFileWatchScanner() throws Exception {
        List scanList = new ArrayList();
        scanList.add(new File(webappPath, "WEB-INF"));

        Scanner scanner = new Scanner();
        scanner.setReportExistingFilesOnStartup(false);
        scanner.setScanInterval(scanIntervalSeconds);
        scanner.setScanDirs(scanList);
        scanner.addListener(new Scanner.BulkListener() {

            @SuppressWarnings("rawtypes")
            public void filesChanged(List changes) {
                try {
                    System.err.println("Loading changes ......");
                    webapp.stop();
                    webapp.start();
                    System.err.println("Loading complete.\n");
                } catch (Exception e) {
                    System.err.println("Error reconfiguring/restarting webapp after change in watched files");
                    e.printStackTrace();
                }
            }
        });
        System.err.println("Starting scanner at interval of " + scanIntervalSeconds + " seconds.");
        scanner.start();
    }

    private static boolean portAvailable(int port) {
        if (port <= 0) {
            throw new IllegalArgumentException("Invalid start port: " + port);
        }

        ServerSocket ss = null;
        DatagramSocket ds = null;
        try {
            ss = new ServerSocket(port);
            ss.setReuseAddress(true);
            ds = new DatagramSocket(port);
            ds.setReuseAddress(true);
            return true;
        } catch (IOException e) {
        } finally {
            if (ds != null) {
                ds.close();
            }
            if (ss != null) try {
                ss.close();
            } catch (IOException e) {
            }
        }
        return false;
    }
}

• 主方法

package test.bshf.clinic.demo;

import test.bshf.clinic.util.JettyServerStarter;

/**
 * 启动jetty容器
 * 
 */
public class JettyStarterTest {

    public static void main(String[] args) {
        String webapp = "src/main/webapp";

        new JettyServerStarter(webapp, 8012, "/clinic-demo").start();
    }
}

解释说明：

pom和工具类直接复制粘贴

主方法

• String webapp = "src/main/webapp";： 是当前web项目的webapp这层目录结构（因为里面包含了class和页面等）

• new JettyServerStarter(webapp, 8012, "/clinic-demo").start(); new 一个Jetty容器，第一个参数是webapp地址，第二个参数是端口号(自定义)，第三个参数是当前web项目名称。

• 访问路径：http://localhost:8012(自定义Jetty的端口)/clinic-demo

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