如何使用eclipse开发felix的OSGI插件

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1、官网下载http://felix.apache.org/downloads.cgi，
当前最新版本6.0.3
运行felix窗口有两种方式
(1) 可以直接下载发布版本
Felix Framework Distribution（org.apache.felix.main.distribution-6.0.3.zip）

解压后目录

进入项目目录，命令行下执行

java -jar ./bin/felix.jar

felix.jar 默认会在当前运行目录的 bundle 文件夹内加载启动所需的插件jar，config 目录下的 config.propeties 和 system.properties 里面加载环境变量，如果将其他目录作为启动根目录，该目录下不存在 felix 启动所需信息，启动就会有问题。项目第一次启动的时候会在启动目录下创建一个felix-cache的目录，用于存放框架运行过程产生的数据，当然该目录可以在启动的时候配置，使用 java -jar ./bin/felix.jar 即可。

(2) 源码导入eclipse运行
下载子项目Main（org.apache.felix.main-6.0.3-project.zip）

解压org.apache.felix.main-6.0.3-project.zip，进入目录，命令行下
运行mvn eclipse:eclipse工程文件，
再输入mvn package，打包编译
File->Import导入到eclipse

在eclipse的org.apache.felix.main.Main类右键运行Run As Java Application

常用命令

lb:查看已装插件包start:运行插件包stop:停止运行插件包install:安装插件包uninstall:删除插件包其它命令可以通过help查看

2、felix开发插件
参考是felix官方例子代码apache-felix-osgi-tutorial里的
apache-felix-tutorial-example-2
apache-felix-tutorial-example-2b
apache-felix-tutorial-example-3
这是一个检查输入单词(英文、中文....)是否正确的例子功能

先定义一个服务类：

package test.penngo.service; /** * 简单的定义了一个字典服务接口，该接口的功能只是简单的验证一个词是否正确。**/public interface DictionaryService{    /**            * 检查 单词是否存在    **/    public boolean checkWord(String word);}

英文词典插件包开发

package tutorial.example2;import java.util.Hashtable;import org.osgi.framework.BundleActivator;import org.osgi.framework.BundleContext;import test.penngo.service.DictionaryService;/** * 英文字典服务插件 **/public class Activator implements BundleActivator {        /**         * 服务启动         *          * @param context the framework context for the bundle.         **/        public void start(BundleContext context) {                Hashtable props = new Hashtable();                props.put("Language", "English");                context.registerService(DictionaryService.class.getName(), new DictionaryImpl(), props);        }        /**         * 服务停止         *          * @param context the framework context for the bundle.         **/        public void stop(BundleContext context) {                // NOTE: The service is automatically unregistered.        }        /**         * 英文词典服务实现         **/        private static class DictionaryImpl implements DictionaryService {                String[] m_dictionary = { "welcome", "to", "the", "osgi", "tutorial" };                /**                 * 英文单词检测                 **/                public boolean checkWord(String word) {                        word = word.toLowerCase();                        for (int i = 0; i < m_dictionary.length; i++) {                                if (m_dictionary[i].equals(word)) {                                        return true;                                }                        }                        return false;                }        }}

META-INF.MF

Manifest-Version: 1.0Bundle-ManifestVersion: 2Bundle-SymbolicName: EnglishBundle-Name: English dictionaryBundle-Description: A bundle that registers an English dictionary serviceBundle-Vendor: penngoBundle-Version: 1.0.0Bundle-Activator: tutorial.example2.ActivatorImport-Package: org.osgi.framework, test.penngo.service

英文词典插件打包导出，eclipse自带的export打包会有问题，本文使用fatjar工具打包，

中文词典插件包开发

package tutorial.example2b; import java.util.Hashtable;import org.osgi.framework.BundleActivator;import org.osgi.framework.BundleContext;import test.penngo.service.DictionaryService;/** * 中文词典包**/public class Activator implements BundleActivator{    public void start(BundleContext context)    {        Hashtable props = new Hashtable();        props.put("Language", "Chinese");        context.registerService(            DictionaryService.class.getName(), new DictionaryImpl(), props);    }     public void stop(BundleContext context)    {        // NOTE: The service is automatically unregistered.    }     /**            *  中文词典服务实现    **/    private static class DictionaryImpl implements DictionaryService    {        // The set of words contained in the dictionary.        String[] m_dictionary =            { "欢迎", "你好", "教程", "模块" };         public boolean checkWord(String word)        {            word = word.toLowerCase();            for (int i = 0; i < m_dictionary.length; i++)            {                if (m_dictionary[i].equals(word))                {                    return true;                }            }            return false;        }    }}

Manifest-Version: 1.0Bundle-ManifestVersion: 2Bundle-SymbolicName: ChineseBundle-Name: Chinese dictionaryBundle-Description: A bundle that registers a Chinese dictionary serviceBundle-Vendor: penngoBundle-Version: 1.1.0Bundle-Activator: tutorial.example2b.ActivatorImport-Package: org.osgi.framework, test.penngo.service

插件打包

客户端调用词典开发，也是作为一个felix插件

package tutorial.example3;import java.io.BufferedReader;import java.io.InputStreamReader;import java.io.IOException;import org.osgi.framework.BundleActivator;import org.osgi.framework.BundleContext;import org.osgi.framework.ServiceReference;import test.penngo.service.DictionaryService; /** * 此客户端在启动时，接收控制台输入，检查输入的单词是否正确，并且打印初相应的检测结果，  * 注意：当我们没有输入任何信息的时候，单词检测便会结束，如果需要重新进入单词检测程序，我们需要重新启动插件。**/public class Activator implements BundleActivator{     public void start(BundleContext context) throws Exception    {        // 获取所有词典插件        ServiceReference[] refs = context.getServiceReferences(            DictionaryService.class.getName(), "(Language=*)");                if (refs != null)        {                System.out.println("=======当前可用词典插件:" + refs.length);            try            {                System.out.println("Enter a blank line to exit.");                BufferedReader in = new BufferedReader(new InputStreamReader(System.in));                String word = "";                while (true)                {                    System.out.print("Enter word: ");                    word = in.readLine();                    if (word.length() == 0)                    {                        break;                    }                     boolean isCorrect = false;                    for(ServiceReference service:refs) {                            DictionaryService dictionary =                                (DictionaryService) context.getService(service);                            if (dictionary.checkWord(word))                            {                                    isCorrect = true;                                System.out.println("Correct.");                            }                                              }                    if(isCorrect == false)                    {                        System.out.println("Incorrect.");                    }                }            } catch (IOException ex) {                     ex.printStackTrace();            }        }        else        {            System.out.println("Couldn't find any dictionary service...");        }    }     /**     * Implements BundleActivator.stop(). Does nothing since     * the framework will automatically unget any used services.     * @param context the framework context for the bundle.    **/    public void stop(BundleContext context)    {        // NOTE: The service is automatically released.    }}

Manifest-Version: 1.0Bundle-ManifestVersion: 2Bundle-SymbolicName: clientBundle-Name: Dictionary clientBundle-Description: A bundle that uses the dictionary service if it finds it at startupBundle-Vendor: penngoBundle-Version: 1.3.0Bundle-Activator: tutorial.example3.ActivatorExport-Package: test.penngo.serviceImport-Package: org.osgi.framework#//注意：test.penngo.service这个包与tutorial.example3打在同一个jar中，如果example3.jar更新，其它依赖test.penngo.service的也需要更新或重启felix.

安装插件
把上边生成的插件包example2.jar,example2b.jar,example3.jar入到org.apache.felix.main-6.0.3项目的plugins文件夹中
安装和运行效果：

通过插件方式开发，后期继续扩展增加其它语言词典（日语，俄语，韩语），不需要重启服务，也不影响已存在的语言词典功能（英文、中文）。

3、开发http服务插件

package test.penngo.http.example;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 TestServlet extends HttpServlet {        @Override        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {                resp.getWriter().write("hello penngo");        }}

package test.penngo.http.example;import org.osgi.framework.BundleActivator;import org.osgi.framework.BundleContext;import org.osgi.framework.ServiceReference;import org.osgi.service.http.HttpService;import org.osgi.util.tracker.ServiceTracker;public class Activator implements BundleActivator {        private ServiceTracker httpTracker;        public void start(BundleContext context) throws Exception {                httpTracker = new ServiceTracker(context, HttpService.class.getName(), null) {                        public void removedService(ServiceReference reference, Object service) {                                // HTTP service is no longer available, unregister our servlet...                                try {                                        ((HttpService) service).unregister("/hello");                                } catch (IllegalArgumentException exception) {                                        // Ignore; servlet registration probably failed earlier on...                                }                        }                        public Object addingService(ServiceReference reference) {                                // HTTP service is available, register our servlet...                                HttpService httpService = (HttpService) this.context.getService(reference);                                try {                                        httpService.registerServlet("/hello", new TestServlet(), null, null);                                } catch (Exception exception) {                                        exception.printStackTrace();                                }                                return httpService;                        }                };                // start tracking all HTTP services...                httpTracker.open();        }        public void stop(BundleContext context) throws Exception {                // stop tracking all HTTP services...                httpTracker.close();        }}

#MANIFEST.MFManifest-Version: 1.0Bundle-ManifestVersion: 2Bundle-SymbolicName: helloBundle-Name: hello penngoBundle-Description: Http Hello WorldBundle-Vendor: penngoBundle-Version: 1.0.0Bundle-Activator: test.penngo.http.example.ActivatorImport-Package: org.osgi.framework, org.osgi.service.http, org.osgi.util.tracker, javax.servlet.http, javax.servlet

注意htpp插件包依赖:

org.apache.felix.http.base-4.0.6.jar,org.apache.felix.http.bridge-4.0.8.jar,org.apache.felix.http.jetty-4.0.10.jar,org.apache.felix.http.servlet-api-1.1.2.jar,org.apache.felix.http.whiteboard-4.0.0.jar

需要先安装上边的插件包，才能正常在felix中运行http功能。
安装运行效果

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感谢各位的阅读，以上就是"如何使用eclipse开发felix的OSGI插件"的内容了，经过本文的学习后，相信大家对如何使用eclipse开发felix的OSGI插件这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是，小编将为大家推送更多相关知识点的文章，欢迎关注！