package com.sun.samples.appserver;

import java.util.ArrayList;
import javax.management.MBeanServer;
import javax.management.MBeanServerFactory;
import javax.management.Notification;
import javax.management.ObjectName;

/**
 *
 * @author Bhavanishankar <bshankar@sun.com>
 *
 */

public class SelfManageJBIComps
 implements SelfManageJBICompsMBean, SelfManageJBICompsConstants {
 
 public synchronized void handleNotification(
 Notification notification,
 Object obj) {

 StringBuffer debugMessage = new StringBuffer
 ("\n\nSelfManageJBIComps :: \n");
 
 System.out.println("SelfManageJBIComps.handleNotification : " +
 notification.getClass().getName());
 
 /**
 * Allow the JBI framework to initialize itself properly.
 */
 if(firstInvocation) {
 firstInvocation = false;
 return;
 }
 
 /**
 * Step 1. Get the connection to the MBean server.
 */
 initMBeanConnection();
 
 /**
 * Step 2. Get the list of deployed service assemblies.
 */
 Object ret = invokeMBean(
 getDeploymentServiceMBeanName(),
 "getDeployedServiceAssemblies",
 new Object[]{},
 new String[]{});
 
 if(ret == null) {
 return;
 }
 String[] serviceAssemblies = (String[]) ret;
 
 /**
 * Step 3. For each service assembly which is in "Started" 
 * state, if the required component's state is not started 
 * then start the component.
 */
 
 for(String sa : serviceAssemblies) {
 debugMessage.append("\n\tProcessing ServiceAssembly " +
 sa + "...");
 /**
 * Step 3.1. Get the state of the service assembly.
 */
 ret = invokeMBean(
 getDeploymentServiceMBeanName(),
 "getState",
 new Object[] {sa},
 new String[] {"java.lang.String"});
 if(ret == null) {
 continue;
 }
 String saState = (String)ret;
 
 debugMessage.append("\n\tState of the ServiceAssembly is " +
 saState);
 
 /**
 * Step 3.2 If the state is "Started" then
 * get the list of Components for this service assembly.
 */
 if(!"Started".equalsIgnoreCase(saState)) {
 continue;
 }
 
 ret = invokeMBean(
 getDeploymentServiceMBeanName(),
 "getComponentsForDeployedServiceAssembly",
 new Object[] {sa},
 new String[] {"java.lang.String"});
 if(ret == null) {
 continue;
 }
 String[] jbiComps = (String[])ret;
 
 for(String jbiComp : jbiComps) {
 debugMessage.append("\n\n\t JBIComponent used " +
 "by " + sa + " is " + jbiComp);
 
 ret = invokeMBean(
 getAdminServiceMBeanName(),
 "getComponentByName",
 new Object[]{jbiComp},
 new String[]{"java.lang.String"});
 if(ret == null) {
 continue;
 }
 ObjectName compName = (ObjectName)ret;
 
 ret = invokeMBean(
 compName,
 "getCurrentState",
 new Object[]{},
 new String[]{});
 
 if(ret == null) {
 continue;
 }
 
 String componentState = (String) ret;
 debugMessage.append("\n\t State of the " + jbiComp +
 " is " + componentState);
 
 if(!"started".equalsIgnoreCase(componentState)) {
 debugMessage.append("\n\t Starting " + 
 jbiComp + "...");
 ret = invokeMBean(
 compName,
 "start",
 new Object[] {},
 new String[] {});
 debugMessage.append("\n\t Successfully started " +
 jbiComp);
 }
 }
 }
 System.out.println(debugMessage.toString());
 }
 
 private static MBeanServer mBeanServer;
 private static boolean firstInvocation = true;
 
 /**
 * Get the connection to the MBean server.
 */
 private synchronized void initMBeanConnection() {
 if(mBeanServer == null) {
 ArrayList<MBeanServer> mBeanServers =
 MBeanServerFactory.findMBeanServer(null);
 if(!mBeanServers.isEmpty()) {
 mBeanServer = mBeanServers.get(0);
 }
 if(mBeanServer == null) {
 System.err.println("Unable " +
 "to obtain connection to MBean server");
 }
 }
 }
 
 private Object invokeMBean(
 ObjectName mBeanName,
 String methodName,
 Object[] params,
 String[] signatures) {
 Object output = null;
 try {
 output = mBeanServer.invoke(mBeanName,
 methodName, params, signatures);
 } catch(Exception ex) {
 ex.printStackTrace();
 }
 return output;
 }
 
 private ObjectName getDeploymentServiceMBeanName() {
 ObjectName objName = null;
 try {
 objName = new ObjectName(DEPLOYMENT_SERVICE_MBEAN);
 } catch(Exception ex) {
 ex.printStackTrace();
 }
 return objName;
 }
 
 private ObjectName getAdminServiceMBeanName() {
 ObjectName objName = null;
 try {
 objName = new ObjectName(ADMIN_SERVICE_MBEAN);
 } catch(Exception ex) {
 ex.printStackTrace();
 }
 return objName;
 }
 
}