自己实现的listener监听器

///定时器TimerTask


web.xml中配置自己写的也可以
<listener>
         <listener-class>com.certusnet.nfv.mano.vim.usage_history.rest.Usage_historyListener</listener-class>
    </listener>


//Usage_historyListener.java

package com.certusnet.nfv.mano.vim.usage_history.rest;

import java.util.Timer;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import com.certusnet.nfv.mano.vim.usage_history.rsclient.IUsage_historyRsClient;

public class Usage_historyListener implements ServletContextListener {

public  static IUsage_historyRsClient usage_historyRsClient;

Timer timer = new Timer();

@Override
public void contextInitialized(ServletContextEvent event) {
// TODO Auto-generated method stub
WebApplicationContext rwp = WebApplicationContextUtils.getRequiredWebApplicationContext(event.getServletContext());
    usage_historyRsClient = (IUsage_historyRsClient) rwp.getBean("usage_historyRsClient");
timer.schedule(new Usage_history_Timer(), 0, 40*1000); 
}
   
@Override
public void contextDestroyed(ServletContextEvent event) {
// TODO Auto-generated method stub
timer.cancel();
}

    public static void main(String[] args) { 
   Timer timer = new Timer(); 
   timer.schedule(new Usage_history_Timer(), 0, 40*1000); 
}

   
}







//Usage_history_Timer.java
package com.certusnet.nfv.mano.vim.usage_history.rest;

import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedList;
import java.util.TimerTask;
import net.sf.json.JSONObject;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import com.certusnet.nfv.mano.exception.ManoException;
import com.certusnet.nfv.mano.vim.ExceptionCode;
import com.certusnet.nfv.mano.vim.HttpsUtil;
import com.certusnet.nfv.mano.vim.usage_history.rsclient.IUsage_historyRsClient;

public class Usage_history_Timer extends TimerTask {
private static Logger logger = Logger.getLogger(Usage_history_Timer.class);
public static LinkedList<JSONObject> vcpus_queue = new LinkedList<JSONObject>();
public static LinkedList<JSONObject> memory_queue = new LinkedList<JSONObject>();
public static LinkedList<JSONObject> disk_queue = new LinkedList<JSONObject>();
@Autowired
private  IUsage_historyRsClient usage_historyRsClient;

public  void findUsage_history_timer() {
try {
if (usage_historyRsClient == null) {
usage_historyRsClient = Usage_historyListener.usage_historyRsClient;
}

String returnStr = usage_historyRsClient.findUsage_history();

// String url = "https://172.16.25.163/" + "/usage_api/get_hypervisor_statistics";
//     String returnStr = new String(HttpsUtil.getMethod(url));
   
logger.info("usage_historyRsClient=" + returnStr);

returnStr = returnStr.replace("null", "\"\"");

JSONObject jsonObj = JSONObject.fromObject(returnStr);
float vcpus_used = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("vcpus_used");
float vcpus = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("vcpus");
float vcpus_usage_temp = vcpus_used / vcpus;
BigDecimal vcpus_usage_big = new BigDecimal(vcpus_usage_temp); 
float vcpus_usage = vcpus_usage_big.setScale(4, BigDecimal.ROUND_HALF_UP).floatValue(); 

float memory_mb_used = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("memory_mb_used");
float memory_mb = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("memory_mb");
float memory_usage_temp = memory_mb_used / memory_mb;
BigDecimal memory_usage_big = new BigDecimal(memory_usage_temp); 
float memory_usage = memory_usage_big.setScale(4, BigDecimal.ROUND_HALF_UP).floatValue(); 

float local_gb_used = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("local_gb_used");
float local_gb = jsonObj.getJSONObject("history_usage").getJSONObject("hypervisor_statistics").getInt("local_gb");
float disk_usage_temp = local_gb_used / local_gb;
BigDecimal disk_usage_big = new BigDecimal(disk_usage_temp); 
float disk_usage = disk_usage_big.setScale(4, BigDecimal.ROUND_HALF_UP).floatValue(); 

if (!"200".equalsIgnoreCase(jsonObj.getString("retCode")))
throw new ManoException(ExceptionCode.FIND_Usage_History_FAILED);


    Date date = new Date();
    SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
   
           JSONObject vcpusObject = new JSONObject(); 
           vcpusObject.put("y", vcpus_usage);
           vcpusObject.put("x", df.format(date));
            vcpus_queue.addLast(vcpusObject);
       if (vcpus_queue.size() > 15) {
       vcpus_queue.removeFirst();
       }
      
           JSONObject memoryObject = new JSONObject(); 
           memoryObject.put("y", memory_usage);
           memoryObject.put("x", df.format(date));
           memory_queue.addLast(memoryObject);
       if (memory_queue.size() > 15) {
       memory_queue.removeFirst();
       }
      
           JSONObject diskObject = new JSONObject(); 
           diskObject.put("y", disk_usage);
           diskObject.put("x", df.format(date));
            disk_queue.addLast(diskObject);
       if (disk_queue.size() > 15) {
       disk_queue.removeFirst();
       }
            System.out.println("vcpus_queue = " + vcpus_queue);
            System.out.println("memory_queue = " + memory_queue);
            System.out.println("disk_queue = " + disk_queue);
} catch (ManoException ex) {
throw ex;
}  catch (Exception ex) {
throw new ManoException(ExceptionCode.FIND_Usage_History_FAILED, ex);
}
}

@Override
public void run() {
// TODO Auto-generated method stub
findUsage_history_timer();

}

   
}