以下的demo引入装饰器模式对Service进行日志的扩展

demo:

Provider

student-manage/Activator.java

package com.demo.service;import java.util.Dictionary;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;import com.demo.service.impl.StudentManage;public class Activator implements BundleActivator {public void start(BundleContext context) throws Exception {System.out.println("register service start...");Dictionary<String, String> prop=new Hashtable<String, String>();prop.put("action", "student_action");context.registerService(IStudentManage.class.getName(), new StudentManage(), prop);System.out.println("register service end...");}public void stop(BundleContext context) throws Exception {}}

Consumer

student-action/Activator.java

package com.demo.action;import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;import com.demo.action.log.LogStudentManager;
import com.demo.action.tracker.StudentManagerTracker;
import com.demo.service.IStudentManage;public class Activator implements BundleActivator{StudentManagerTracker managerTracker ;public void start(BundleContext context) throws Exception {System.out.println("action start begin...");managerTracker=new StudentManagerTracker(context);//开启managerTracker.open();//获取服务IStudentManage service=(IStudentManage)managerTracker.getService();service.add();System.out.println("action start end...");}public void stop(BundleContext context) throws Exception {//关闭managerTracker.close();}}

student-action/StudentManagerTracker.java

package com.demo.action.tracker;import org.omg.PortableInterceptor.INACTIVE;
import org.osgi.framework.BundleContext;
import org.osgi.framework.Filter;
import org.osgi.framework.ServiceReference;
import org.osgi.util.tracker.ServiceTracker;
import org.osgi.util.tracker.ServiceTrackerCustomizer;import com.demo.action.log.LogStudentManager;
import com.demo.service.IStudentManage;public class StudentManagerTracker extends ServiceTracker {public StudentManagerTracker(BundleContext context) {super(context, IStudentManage.class.getName(), null);}@Overridepublic Object addingService(ServiceReference reference) {IStudentManage manage=new LogStudentManager(context, reference);return manage;}@Overridepublic void open() {super.open();}}

student-action/LogStudentManager.java

package com.demo.action.log;import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;import com.demo.service.IStudentManage;public class LogStudentManager implements IStudentManage {IStudentManage studentManage;BundleContext context;ServiceReference reference;public LogStudentManager(BundleContext context, ServiceReference reference) {this.context = context;this.reference = reference;}public void add() {studentManage=(IStudentManage) context.getService(reference);System.out.println("log start...");studentManage.add();System.out.println("log end...");}}

结果: