Management and Monitoring Programming Examples

One example demonstrates the use of an MBean server to manage and monitor a node in a distributed system, and the other example acts as the managed node.

JMX Manager Node Example

package quickstart;

import java.util.Set;
import javax.management.ObjectName;
import org.apache.geode.cache.Cache;
import org.apache.geode.cache.CacheFactory;
import org.apache.geode.distributed.DistributedMember;
import org.apache.geode.management.ManagementService;
import org.apache.geode.management.RegionMXBean;

/**
 * Example of a JMX Manager Node. It first creates a cache. 
 * Then for each member of Distributed System it retrieves RegionMXBean and uses its data.
 *   
 * @author GemStone Systems, Inc.
 * 
 * @since 7.0
 */
public class ManagerNode {

  /**
   * @param args
   */
  public static final String EXAMPLE_REGION_NAME = "exampleRegion";

  public static void main(String[] args) throws Exception {

    //Set waiting period for federation in milliseconds
    final int JMX_WAIT_PERIOD_FOR_FEDERATION_UPDATE = 2500;


    System.out
        .println("Connecting to the distributed system and creating the cache.");

    // Create the cache which causes the cache-xml-file to be parsed
    Cache cache = new CacheFactory()
                  .set("name", "ManagerNode")
                  .set("statistic-sampling-enabled", "true")
                  .set("jmx-manager-start","true")
                  .set("jmx-manager","true")      
                  .set("jmx-manager-port","2576")
                  .set("cache-xml-file", "xml/Managed-node.xml").create(); 

    // Retrieve service
    System.out.println("Retrieving service ...");

    //ManagementService.getManagementService() will create a service in case not already created
    //ManagementService.getExistingManagementService() will return existing one, otherwise null.
    ManagementService service = ManagementService.getManagementService(cache);
    System.out.println("Retrieved service ");


    //Retrieve distributed system members
    System.out.println("Retrieving distributed members ...");
    Set<DistributedMember> dsMembers = cache.getDistributedSystem()
        .getAllOtherMembers();    
    System.out.println("Retrieved " +dsMembers.size()+ " distributed members ");


    //Sleep is needed for federation data to get published
    System.out.println("Retrieving RegionMXBean for members in DS ...");

    try {
      Thread.sleep(JMX_WAIT_PERIOD_FOR_FEDERATION_UPDATE);
    } catch (Exception e) {

    }

    for (DistributedMember dsMember : dsMembers) {
      System.out.println("Retrieved RegionMXBean for member "+ dsMember.getId());    

      //Get region member bean name using region path. 
      ObjectName regionMBeanName = service.getRegionMBeanName(dsMember, "/"
          + EXAMPLE_REGION_NAME);
      System.out.println("regionMBeanName " + regionMBeanName);

      //Get Region MBean Proxy
      RegionMXBean regionMXBean = service.getMBeanInstance(regionMBeanName,
          RegionMXBean.class);

      // Validate regionMXbean
      if(regionMXBean != null){        
        System.out.println("Entry count in " + EXAMPLE_REGION_NAME + " is =" + regionMXBean.getEntryCount());
      }else{
        System.out.println("Retrieved RegionMXBean is null.");        
      }
    }

    // Close the cache and disconnect from GemFire distributed system
    System.out.println("Closing the cache and disconnecting.");
    cache.close();


    //Complete Managed Node by pressing enter in managed node console
    System.out.println("");
    System.out.println("Press enter in Managed Node");

  }
}

GemFire Managed Node Example

package quickstart;

import java.io.BufferedReader;
import java.io.InputStreamReader;

import org.apache.geode.cache.Cache;
import org.apache.geode.cache.CacheFactory;
import org.apache.geode.cache.Region;
import org.apache.geode.management.ManagementService;
import org.apache.geode.management.RegionMXBean;

/**
 * In this example of Managed Node. 
 * 1. It creates a cache and adds entries in it.
 * 2. From ManagementService it retrieves service. 
 * 3. From service gets Region Mbean.
 *  
 * 
 * @author GemStone Systems, Inc.
 * 
 * @since 7.0
 */

public class ManagedNode {

  /**
   * @param args
   */
  public static final String EXAMPLE_REGION_NAME = "exampleRegion";

  public static void main(String[] args) throws Exception {

    //Set waiting period for federation in milliseconds
    final int JMX_WAIT_PERIOD_FOR_FEDERATION_UPDATE = 2500;

    System.out
        .println("Connecting to the distributed system and creating the cache.");

    // Create the cache which causes the cache-xml-file to be parsed
    System.out.println("Creating cache using Mbean.xml");
    Cache cache = new CacheFactory().set("name", "ManagedNode")
                      .set("log-level", "fine")
                      .set("statistic-sampling-enabled", "true")                      
                      .set("cache-xml-file", "xml/Managed-node.xml").create();

    System.out.println("Created cache using Mbean.xml");

    // Create one sample region
    Region<Object, Object> region = cache.getRegion("/" + EXAMPLE_REGION_NAME);

    // Add some entries to region
    if (region != null) {
      System.out.println("Adding key and value to region in member "
          + cache.getDistributedSystem().getDistributedMember().getId());
      for (int count = 0; count < 10; count++) {
        String key = "key" + count;
        String value = "value" + count;
        region.put(key, value);
      }
    }

    System.out.println("Retrieving service using cache ...");

    // Retrieve service in this node
    ManagementService service = ManagementService
        .getExistingManagementService(cache);
    System.out.println("Retrieved service.");

    System.out.println("Retrieving RegionMXBean for " + EXAMPLE_REGION_NAME);   

    try{
      Thread.sleep(JMX_WAIT_PERIOD_FOR_FEDERATION_UPDATE);
    }catch(Exception e){

    }

    RegionMXBean regionBean = service.getLocalRegionMBean("/"
        + EXAMPLE_REGION_NAME);



    if (regionBean != null) {
      System.out.println("Retrieved RegionMXBean for " + EXAMPLE_REGION_NAME);
      System.out.println("Entry count for " + EXAMPLE_REGION_NAME + " is="
          + regionBean.getEntryCount());

      System.out.println("Start Manager Node and wait till it completes");

    } else {
      System.out.println("Could not retriev RegionMXBean for "
          + EXAMPLE_REGION_NAME);
    }

    // Wait till user input, after manager node completes
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(
        System.in));
    bufferedReader.readLine();

    // Close the cache and disconnect
    System.out.println("Closing the cache and disconnecting.");
    cache.close();
  }

}