osgi学习笔记（一）

最新推荐文章于 2022-03-18 15:03:37 发布

最新推荐文章于 2022-03-18 15:03:37 发布 · 135 阅读

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#OSGI #Servlet #IE #Eclipse #HTML

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本文详细介绍了一个简单的WebOSGI示例项目开发过程，包括使用Eclipse创建插件项目、配置MANIFEST.MF文件、编写Activator类和服务注册逻辑等关键步骤。

初步了解OSGI就被这种思想吸引了。谁叫我是普通人呢，只能一步一步的跟着前辈们学习。

开发工具：eclipse-jee-galileo-SR2-win32.zip

启动工具后找到Run Configurations，你会发现这么一个东西的存在。

执行run后你在Console发现了这么一个东西：

这是我第一次与之见面的印象。仿佛变得模糊了，难道是我功底不够深厚........
于是找了两本武功秘笈进行修炼。
OSGI实战.rar ,OSGI进阶.rar ,你别说还真有效果。秘笈上讲的登录设计很不错。

看了之后根据自己的理解先写上一个简单的WebOSGIDemo:

第一步：创建Plug-in Project工程：

点Next：

Finish。

第二步，打开MANIFEST.MF文件：

第三步，创建以下文件：

Activator类：

package org.forever.webosgi;

import java.util.ArrayList;
import java.util.List;

import org.forever.webosgi.action.AbstractAction;
import org.forever.webosgi.action.UserAction;
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceEvent;
import org.osgi.framework.ServiceListener;
import org.osgi.framework.ServiceReference;
import org.osgi.service.http.HttpService;

public class Activator implements BundleActivator, ServiceListener {
	private BundleContext bundleContext;
	private ServiceReference serviceRef;
	private List<AbstractAction> servletList = new ArrayList<AbstractAction>();
	
	public BundleContext getBundleContext() {
		return bundleContext;
	}

	public void setBundleContext(BundleContext bundleContext) {
		this.bundleContext = bundleContext;
	}

	public ServiceReference getServiceRef() {
		if (null == serviceRef) {
			synchronized (this) {
				if (null == serviceRef) {
					serviceRef = bundleContext.getServiceReference(HttpService.class.getName());
				} 
			}
		}
		return serviceRef;
	}
	
	public HttpService getService(){
		return (HttpService) bundleContext.getService(getServiceRef());
	}

	public void setServiceRef(ServiceReference serviceRef) {
		this.serviceRef = serviceRef;
	}

	@Override
	public void start(BundleContext bundleContext) throws Exception {
		System.out.println("************Activator.start()**************");
		this.bundleContext = bundleContext;
		UserAction userAction = new UserAction(this); 
		servletList.add(userAction);
	}

	@Override
	public void stop(BundleContext bundleContext) throws Exception {
		System.out.println("************Activator.stop()*****************");
		for (AbstractAction item : servletList) {
			item.unregisterServlet();
		}
	}

	@Override
	public void serviceChanged(ServiceEvent event) {
		System.out.println("Activator.serviceChanged()");
		System.out.println("event.getType()=" + event.getType());

	}

}

AbstractAction类：

package org.forever.webosgi.action;

import javax.servlet.http.HttpServlet;

import org.forever.webosgi.Activator;

public abstract class AbstractAction extends HttpServlet {

	private static final long serialVersionUID = -4607634443833513971L;
	protected Activator activator;

	protected AbstractAction(){
		
	}
	
	public AbstractAction(Activator activator) {
		this.activator = activator;
		registerServlet();
	}

	public Activator getActivator() {
		return activator;
	}

	public void setActivator(Activator activator) {
		this.activator = activator;
	}

	public abstract void registerServlet();

	public abstract void unregisterServlet();
}

UserAction类：

package org.forever.webosgi.action;

import java.io.IOException;

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

import org.forever.webosgi.Activator;
import org.osgi.service.http.HttpService;

public class UserAction extends AbstractAction {

	private static final long serialVersionUID = 605084525972358889L;
	
	public UserAction(Activator activator) {
		super(activator);
		
	}

	public void registerServlet() {
		HttpService http = activator.getService();
		try {
			http.registerServlet("/WebOSGI/user/login.action",this,null, null);
			http.registerResources("/WebOSGI/page/user", "org/forever/page/user", null);
			System.out.println("注册UserAction成功！");
		} catch (Exception e) {
			e.printStackTrace();
		} 
	}

	@Override
	public void unregisterServlet() {
		HttpService http = activator.getService();
		http.unregister("/WebOSGI/user/login.action");
		http.unregister("/WebOSGI/page/user");
		System.out.println("卸载UserActoin成功！");
	}

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		System.out.println("userName=" + req.getParameter("userName"));
		resp.sendRedirect("/WebOSGI/page/user/Login.html");
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		doGet(req, resp);
	}

	

}

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>登陆页面</title>
</head>
<body>
	<form action="/WebOSGI/user/login.action">
		userName:<input type="text" id="userName" name="userName"/><br/>
		<input type="submit" value="提交"/>
	</form>
</body>
</html>

第四步：

ok开发完毕：