mmservlet.java

mobile to system control

/*
 *   This file is part of MobiMon.
 *
 *   MobiMon is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   MobiMon is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.

 *   You should have received a copy of the GNU General Public License
 *   along with MobiMon; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
/*
 * MMServlet.java
 *
 * Created on February 1, 2003, 5:53 PM
 */

package mobimon.servlet;

import java.net.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.management.*;
import javax.management.monitor.*;
import com.sun.jdmk.comm.ConnectorAddress;
import com.sun.jdmk.comm.HeartBeatNotification;
import com.sun.jdmk.comm.RmiConnectorAddress;
import com.sun.jdmk.comm.RmiConnectorClient;
import com.sun.jdmk.ServiceName;
import mobimon.common.*;

/**
 *
 * @author  jan
 * @version
 */
public class MMServlet extends HttpServlet implements NotificationListener {
    
    private ResourceBundle servletResources;
    
    private Hashtable hostConnections = new Hashtable();
    
    private static String SERVLET_RESOURCE_FILE = "mobimon.servlet.MMServlet";
    
    private int reconnectMaxRetries = 5;
    
    private Object lock;
    
    /** Initializes the servlet.
     */
    public void init(ServletConfig config) throws ServletException {
        super.init(config);
        lock = new Object();
        readProperties();
        if (servletResources != null) {
            log("Properties read");
            String hosts = servletResources.getString("mobimon.hosts");
            StringTokenizer st = new StringTokenizer(hosts);
            while (st.hasMoreTokens()) {
                String host = st.nextToken();
                RmiConnectorClient rcc = new RmiConnectorClient();
                RmiConnectorAddress address = new RmiConnectorAddress
                (host, ServiceName.RMI_CONNECTOR_PORT,
                ServiceName.RMI_CONNECTOR_SERVER);
                try {
                    log("Trying connection to " + host);
                    rcc.connect(address) ; // CONNECTION
                    rcc.addHeartBeatNotificationListener(this, null, null);
                    subscribeToMonitorNotifications(rcc);
                    hostConnections.put(host, rcc);
                    log("Connected to " + host);
                } catch (Exception e) {
                    log("Unable to connect to host " + host);
                }
            }
        }
    }
    
    /** Destroys the servlet.
     */
    public void destroy() {
        for (Enumeration e = hostConnections.elements(); e.hasMoreElements();) {
            RmiConnectorClient rcc = (RmiConnectorClient)e.nextElement();
            try {
                rcc.disconnect();
            } catch (Exception ex) {}
        }
    }
    
    /** Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     */
    protected void processRequest(HttpServletRequest request,
    HttpServletResponse response) throws ServletException, java.io.IOException {
        response.setContentType("text/plain");
        ServletOutputStream sos = response.getOutputStream();
        byte[] barr = null;
        int pageNo = 0;
        
        String whatNext = request.getParameter("nodes");
        if (whatNext != null) {
            barr = listNodes();
        } else {
            whatNext = request.getParameter("host");
            if (whatNext != null) {
                String hostName = whatNext;
                whatNext = request.getParameter("domain");
                if (whatNext != null) {
                    String domain = whatNext;
                    barr = listMBeans(hostName, domain);
                } else {
                    whatNext = request.getParameter("mbean");
                    if (whatNext != null) {
                        String mBeanName = whatNext;
                        whatNext = request.getParameter("action");
                        if (whatNext != null) {
                            String action = whatNext;
                            whatNext = request.getParameter("desc");
                            if (whatNext != null) {
                                if (whatNext.equals("a")) {
                                    barr =
                                    getDescription(hostName, mBeanName, action);
                                } else if (whatNext.equals("p")) {
                                    barr =
                                    getParameters(hostName, mBeanName, action);
                                }
                            } else {
                                Object o = performAction
                                (hostName, mBeanName, action, request);
                                if (o instanceof Page) {
                                    Page p = (Page)o;
                                    barr = p.getPageContents();
                                    pageNo = p.getPageNo();
                                } else {
                                    barr = (byte[])o;
                                }
                            }
                        } else {
                            barr = listActions(hostName, mBeanName);
                        }
                    } else {
                        barr = listDomains(hostName);
                    }
                }
            } else {
                barr = "Unrecognized request".getBytes();
            }
        }
        if (barr != null) {
            response.setContentLength(barr.length);
            response.setIntHeader("Page", pageNo);
            sos.write(barr);
        }
        
        sos.close();
    }
    
    /** Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, java.io.IOException {
        processRequest(request, response);
    }
    
    /** Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, java.io.IOException {
        processRequest(request, response);
    }
    
    /** Returns a short description of the servlet.
     */
    public String getServletInfo() {
        return "MobiMon Servlet";
    }
    
    private byte[] listNodes() {
        StringBuffer sb = new StringBuffer();
        for (Enumeration e = hostConnections.keys(); e.hasMoreElements();) {
            sb.append((String)e.nextElement()).append("\n");
        }
        return sb.toString().getBytes();
    }
    
    private byte[] listMBeans(String host, String domain) {
        StringBuffer sb = new StringBuffer();
        RmiConnectorClient connectorClient = null;
        try {
            connectorClient = connect(host);
            Set s = connectorClient.queryNames(new ObjectName(domain + ":*"),
            null);
            Iterator it = s.iterator();
            while (it.hasNext()) {
                ObjectName mBeanName = (ObjectName)it.next();
                String name = mBeanName.getKeyPropertyListString();
                sb.append(name).append("\n");
            }
        } catch (Exception e) {
            log(e.getClass().getName(), e);
            sb.append("Exception occured: ").append(e.getMessage());
        }
        return sb.toString().getBytes();
    }
    
    private byte[] listActions(String host, String mbean) {
        StringBuffer sb = new StringBuffer();
        RmiConnectorClient connectorClient = null;
        try {
            connectorClient = connect(host);
            ObjectName mBeanName = new ObjectName(mbean);
            MBeanInfo mbi = connectorClient.getMBeanInfo(mBeanName);
            MBeanAttributeInfo[] mai = mbi.getAttributes();
            for (int i = 0; i < mai.length; i++) {
                if (mai[i].isReadable()) {
                    if (mai[i].getType().equals("boolean")) {
                        sb.append(mai[i].isIs() ? "is" : "get");
                    } else {
                        sb.append("get");
                    }
                }
                sb.append(mai[i].getName()).append("\n");
                if (mai[i].isWritable()) {
                    sb.append("set").append(mai[i].getName()).append("\n");
                }
            }
            MBeanOperationInfo[] moi = mbi.getOperations();
            for (int i = 0; i < moi.length; i++) {
                sb.append(moi[i].getName()).append("\n");
            }
        } catch (Exception e) {
            log(e.getClass().getName(), e);
            sb.append("Exception occured: ").append(e.getMessage());
        }
        return sb.toString().getBytes();
    }
    
    private Object performAction(String host, String mbean, String action,
    HttpServletRequest request) {
        Object o = null;
        byte[] barr = null;
        RmiConnectorClient connectorClient = null;
        try {
            connectorClient = connect(host);
            ObjectName mBeanName = new ObjectName(mbean);
            log("Performing action " + action);
            boolean getterAction = false;
            boolean setterAction = false;
            String attrName = null;
            if (action.startsWith("get") || action.startsWith("set")
            || action.startsWith("is")) {
                attrName = action.startsWith("is")
                ? action.substring(2) : action.substring(3);
                MBeanInfo mbi = connectorClient.getMBeanInfo(mBeanName);
                MBeanAttributeInfo[] mai = mbi.getAttributes();
                for (int i = 0; i < mai.length; i++) {
                    if (mai[i].getName().equals(attrName)) {
                        getterAction = (action.startsWith("get")
                        || action.startsWith("is"));
                        setterAction = action.startsWith("set");
                        break;
                    }
                }
            }
            if (getterAction) {
                if (request.getHeader("Page") != null) {
                    int pageNo = request.getIntHeader("Page");
                    if (pageNo != 0) {
                        o = invokePageOperation
                        (connectorClient, mBeanName, action, pageNo);
                    } else {
                        o = getMBeanAttribute
                        (connectorClient, mBeanName, attrName);
                    }
                } else {
                    o = getMBeanAttribute(connectorClient, mBeanName, attrName);
                }
            } else if (setterAction) {
                String value = request.getParameter(attrName);
                if ((value == null) || (value.length() < 1)) {
                    barr = ("No attribute value specified for action "
                    + action).getBytes();
                } else {
                    barr = setMBeanAttribute
                    (connectorClient, mBeanName, attrName, value);
                }
            } else {
                o = invokeMBeanOperation
                (connectorClient, mBeanName, action, request);
            }
        } catch (Exception e) {
            log(e.getClass().getName(), e);
            barr = ("Exception occured: " + e.getMessage()).getBytes();
        }
        if (barr != null) o = barr;
        return o;
    }
    
    private Object getMBeanAttribute(RmiConnectorClient connectorClient,
    ObjectName mBeanName, String attrName) {
        try {
            Object o = connectorClient.getAttribute(mBeanName, attrName);
            if (o instanceof Page) return o;
            return convertReturnValue(o, "");
        } catch (Exception e) {
            log(e.getClass().getName(), e);
            return("Exception occured: " + e.getMessage()).getBytes();
        }
    }
    
    private byte[] setMBeanAttribute(RmiConnectorClient connectorClient,
    ObjectName mBeanName, String attrName, String value) {
        try {
            MBeanInfo mbi = connectorClient.getMBeanInfo(mBeanName);
            MBeanAttributeInfo[] mai = mbi.getAttributes();
            for (int i = 0; i < mai.length; i++) {
                if (mai[i].getName().equals(attrName)) {
                    String type = mai[i].getType();
                    try {
                        Attribute a =
                        new Attribute(attrName, convertValue(value, type));
                        connectorClient.setAttribute(mBeanName, a);
                        return ("Attribute " + attrName + " set").getBytes();
                    } catch (MMParameterException mpe) {
                        return
                        ((attrName + ": " + mpe.getMessage()).getBytes());
                    }
                }
            }
            return("Attribute " + attrName + " not found").getBytes();
        } catch (Exception e) {
            log(e.getClass().getName(), e);
            return("Exception occured: " + e.getMessage()).getBytes();
        }
    }
    
    private Object invokeMBeanOperation(RmiConnectorClient connectorClient,
    ObjectName mBeanName, String action, HttpServletRequest request) {
        try {
            MBeanInfo mbi = connectorClient.getMBeanInfo(mBeanName);
            MBeanOperationInfo moi[] = mbi.getOperations();
            for (int i = 0; i < moi.length; i++) {
                if (moi[i].getName().equals(action)) {
                    String retType = moi[i].getReturnType();
                    Object retVal;
                    MBeanParameterInfo mpi[] = moi[i].getSignature();
                    if (mpi.length > 0) {