Example of using the Administration API to get cluster members, hostnames, and bootstrap port address information

The following code is an example of using the Administration API to get cluster members, host names, and bootstrap port address information:

package com.ibm.mdm.jmxtest;

import java.io.File;
import java.io.FileWriter;
import java.io.StringBufferInputStream;
import java.util.Properties;
import java.util.Set;
import java.util.Vector;

import javax.management.ObjectName;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;

/*
 * You can import the following classes from the 
 * com.ibm.ws.runtime_6.1.0.jar available with 
 * the IBM Software Development Platform.
 * 
 *  The these classes are documented here:
 *  http://publib.boulder.ibm.com/infocenter/wasinfo/v7r0/index.jsp?_
	* topic=/com.ibm.websphere.javadoc.doc/web/mbeanDocs/index.html
 */
import com.ibm.websphere.management.AdminClient;
import com.ibm.websphere.management.AdminClientFactory;
import com.ibm.websphere.management.wlm.ClusterMemberData;
import com.ibm.ws.exception.WsException;


public class JMXClientClass {
	
	private AdminClient adminClient = null;

	public void connectToWAS() throws WsException {
		
        java.util.Properties props = new java.util.Properties();
        props.setProperty(AdminClient.CONNECTOR_TYPE, AdminClient.CONNECTOR_TYPE_SOAP);
        props.setProperty(AdminClient.CONNECTOR_HOST, "suse3");
        props.setProperty(AdminClient.CONNECTOR_PORT, "8879");

		adminClient = AdminClientFactory.createAdminClient(props);
		
	}
	
	public void getClusterMemberBootStraps() {
		
        try {
        	
        	/*
        	 * This method will write the bootstrap port numbers and servers 
        	 * for the cluster on which MDM is running to file. This file 
        	 * can be retrieved and updated each time a client application 
        	 * accesses MDM.  With this approach, the client application can 
        	 * have a continuously updated list of cluster members it can 
        	 * access when retrieving the EJB Home interface for MDM
        	 */
			File file = new File("C:/MDM/output/MDMCluster.txt");
			FileWriter fileWriter = new  FileWriter(file);

			/*
			 * We must build an XML Document containing the topology for Cell and 
			 * Cluster in which MDM is installed.  Here is a function we've written 
			 * to do that.
			 * We'll use this XML document to get the host and node information.
			 */
			Document DOM = getTargetTreeMBean();

			
        	/*
        	 * First we must establish a connection to MBean server on the 
        	 * WAS deployment manager
        	 */
			if (adminClient == null) {
				this.connectToWAS();
			}

			/*
   			 * The Various MBeans are documented here:
   			 * http://publib.boulder.ibm.com/infocenter/wasinfo/v7r0/index.jsp?
										topic=/com.ibm.websphere.javadoc.doc/web/mbeanDocs/index.html
   			 * The first task is to query the MBean server and to find the 
   			 * MBean for our Cluster.  Our hypothetical cluster is named "c1".
   			 * The WAS API (i.e. adminClient) will return a SET of clusters 
   			 * matching our search criteria.  Most likely it will be a set of one.
   			 */
			ObjectName clusterQueryName = new ObjectName("WebSphere:*,type=Cluster,name=c1");
			Set<ObjectName> clusters = adminClient.queryNames(clusterQueryName, null);
			
			String memberName = null;
			String nodeName = null;
			String hostName = null;
			int bootStrapPortNum = 0;
			String outputString = null;
			
			
			for (ObjectName objCluster : clusters) {  // We iterate through the set of clusters
				System.out.println(objCluster.getCanonicalName());
				ClusterMemberData[] obj = (ClusterMemberData[])adminClient
								.invoke(objCluster, "getClusterMembers", null, null);
				/*
				 *  For details on this API method please see:
				 *  http://publib.boulder.ibm.com/infocenter/wasinfo/v7r0/index.jsp?topic=/com.ibm.websphere.javadoc.doc/web/mbeanDocs/index.html
				 *  				 */
				// We are going to store a vector of the nodes in which each cluster member resides
				Vector<String> nodes = new Vector<String>();   
				 
				
				for (int i = 0; i < obj.length; i++) {
					memberName = obj[i].memberName;
					nodeName = obj[i].nodeName;
					hostName = getHostNameforNode(nodeName, DOM);
					if (!nodes.contains(nodeName)) {  
						// Storing node name in the vector of node names
						nodes.add(nodeName);
					}
					/*
					 * Having got the Server names and node names of the cluster members, we can now
					 * make another call to the WAS API (i.e. adminClient) to retrieve the Object 
					 * Request Brokers for each.  Each ORB has a property called "bootStrapPort".  
					 * We'll retrieve that property as the bootstrap port number we are seeking
					 */
					String orbQuery = 
						String.format("WebSphere:*,type=ORB,j2eeType=RMI_IIOPResource,J2EEServer=%1$s,node=%2$s", 
										memberName, nodeName);
					Set<ObjectName> orbSet = adminClient.queryNames(new ObjectName(orbQuery),null);
					bootStrapPortNum = 0;
					for (ObjectName orbObj : orbSet) {
						bootStrapPortNum = (Integer)adminClient.getAttribute(orbObj, "bootstrapPort");
						outputString = String.format("Node=%1$s,Server=%2$s,BootStrap=%3$s,HostName=%4$s", 
								nodeName, memberName, bootStrapPortNum, hostName) + "\n";
						fileWriter.write(outputString);
					}
				}	
				
				/*
				 * Now get all the bootstrap port numbers for the nodeagents
				 */
				for (String strNodeName : nodes) {
					String orbQuery = 
						String.format("WebSphere:*,type=ORB,j2eeType=RMI_IIOPResource,J2EEServer=%1$s,node=%2$s", 
								"nodeagent", strNodeName);
					hostName = getHostNameforNode(strNodeName, DOM);
					Set<ObjectName> orbSet = adminClient.queryNames(new ObjectName(orbQuery), null);
					for (ObjectName orbObj : orbSet) {
						bootStrapPortNum = (Integer)adminClient.getAttribute(orbObj, "bootstrapPort");
						outputString = String.format("Node=%1$s,BootStrap=%2$s,HostName=%3$s", 
										strNodeName, bootStrapPortNum, hostName) + "\n";
						fileWriter.write(outputString);
					}
				}
				fileWriter.flush();
				fileWriter.close();
				
			}
			
		
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} 
		
	}
	
	private String getHostNameforNode(String nodeName, Document DOM) {
		// TODO Auto-generated method stub

		String xPathQuery = 
				String.format("//node[@name='%1$s']/property[@name='hostName']/@value", nodeName);
		String hostNameforNode = JMXClientClass.executeXPATHQuery(DOM, xPathQuery);
		
		return hostNameforNode;
	}

	public Document getTargetTreeMBean() {
		
		Document DOM = null;
		try {
			if (adminClient == null) {
				this.connectToWAS();
			}
			
			ObjectName endPointMgr = new ObjectName("WebSphere:*,type=TargetTreeMbean,process=dmgr");
			Set<ObjectName> endPointMgrSet = adminClient.queryNames(endPointMgr, null);
			int i = 0;
			for (ObjectName objName : endPointMgrSet) {
				System.out.println(objName.getCanonicalName());
				
				DOM = JMXClientClass.getDOMFromString(
					(String)adminClient.invoke(objName, "getTargetTree", null, null));
				break;
			}
			
		} catch (Exception e) {
			e.printStackTrace();
		}
		return DOM;
	}
	
	@SuppressWarnings("deprecation")
	public Document getDOMFromString(String theRequest) throws Exception {
		
		StringBufferInputStream sb = new StringBufferInputStream(theRequest);
		DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
		DocumentBuilder db = dbf.newDocumentBuilder();
		Document dom = db.parse(sb);
		
		return dom;
		
	}
	
	public String executeXPATHQuery(Document DOM, String xPathQuery) {
		
		String nodeValues = "";
		try {
			XPathFactory factory = XPathFactory.newInstance();
			XPath xpath = factory.newXPath();
			XPathExpression expr;
			expr = xpath.compile(xPathQuery);
			Object result = expr.evaluate(DOM, XPathConstants.NODESET);
			NodeList nodes = (NodeList) result;
			for (int j = 0; j < nodes.getLength(); j++) {
				if (nodeValues.length() > 0) {
					nodeValues = nodeValues + ",";
				}
			    nodeValues = nodeValues + nodes.item(j).getNodeValue();
			}
		} catch (XPathExpressionException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return nodeValues;
		
	}
	
}

In the above example code, the method called getTargetTreeMBean() invokes the TargetTreeMBean on the WebSphere® Application Server Admin API. This MBean will return an XML document that looks like this:

-<cellGroup name="target">
  <!-- cell section -->
 -<cell name="SUSE3Cell01">
    <property name="isWebSphere" value="true" />
	<property name="arfmMode" value="Automatic" />
	<property name="magicN" value="-1" />
	<property name="magicNMode" value="false" />
	<property name="boostCPUThreshold" value="90" />
	<property name="profilerPeriod" value="60000" />
	<property name="profilerHalfLife" value="600000" />
	<property name="useODRs" value="true" />
	<property name="useProcessCPU" value="true" />
	<property name="useOverhead" value="false" />
	<property name="cp.enableAdminAuthorizationCache" value="true" />
	<!-- node section -->
   -<node name="SUSE3Node01">
      <property name="isWebSphere" value="true" />
	  <property name="isXD" value="false" />
	  <property name="hostName" value="SUSE3.site" />
	  <!-- server section -->
	 -<server name="server2">
	    <property name="id" priority="1" value="1910069938" />
		<property name="type" priority="1" value="APPLICATION_SERVER" />
		<property name="state" priority="1" value="STARTED" />
		<property name="ODR" priority="1" value="false" />
		<property name="reachable" value="true" />
		<property name="weight" priority="1" value="2" />
		<property name="staticweight" priority="1" value="2" />
		<property name="threadPoolMin" priority="1" value="20" />
		<property name="threadPoolMax" priority="1" value="20" />

This document contains all the information related to Cell (whose name happens to be SUSE3Cell01) containing our cluster. Our code will search through this XML document looking for the host name attribute for each Node that contains the cluster member. The following code snippet (taken from the method getHostNameforNode() ) illustrates this:

String xPathQuery = 
				String.format("//node[@name='%1$s']/property[@name='hostName']/@value", nodeName);
		String hostNameforNode = JMXClientClass.executeXPATHQuery(DOM, xPathQuery);

Where %1$s represents the node name containing one of our cluster members. This sample program writes the cluster information to a text file. An example of the output of such a text file is:

Node=SUSE3Node01,Server=server1,BootStrap=2809,HostName=SUSE3.site
Node=SUSE3Node02,Server=server3,BootStrap=2812,HostName=suse3.site
Node=SUSE3Node01,BootStrap=2810,HostName=SUSE3.site
Node=SUSE3Node02,BootStrap=2813,HostName=suse3.site