topologymanagerbean.java

Sun公司Dream项目

/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * http://www.opensource.org/licenses/cddl1.php
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * http://www.opensource.org/licenses/cddl1.php.  If 
 * applicable, add the following below this CDDL HEADER, 
 * with the fields enclosed by brackets "[]" replaced 
 * with your own identifying information: 
 * Portions Copyright [yyyy]
 * [name of copyright owner]
 */ 

/*
 * $(@)TopologyManagerBean.java $Revision: 1.1.1.1 $ $Date: 2006/03/15 13:12:10 $
 * 
 * Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
 */
/**
 *
 * @version: 1.0
 * @date: Jan 28, 2003
 * 
 * Modified: [e-mail]
 *
 */
package com.sun.sjc.idtv.vod.server.topologymanager;

import java.util.*;
import java.sql.*;
import javax.ejb.*;
import javax.sql.*;
import javax.naming.*;
import java.rmi.*;

import com.sun.sjc.idtv.vod.shared.data.*;

/**
 * Implementation bean for the <code>TopologyManager</code> interface, <code>TopologyManager</code>
 * defines all possible business methods for the bean.
 *
 * @see TopologyManager
 * @see TopologyManagerHome
 */
public class TopologyManagerBean implements SessionBean {

    private  javax.ejb.SessionContext m_ctx = null; 
    public static final int QUERYTIMEOUT = 60;
    private DataSource dataSource;
   
    /**
     * Sets the session context. Required by EJB spec.
     * @param ctx A SessionContext object.
     */
    public void setSessionContext(javax.ejb.SessionContext ctx) { 
        m_ctx = ctx; 
	try {
	    InitialContext ic = new InitialContext();
	    //dataSource = (DataSource) ic.lookup("java:comp/env/jdbc/vod");
	    dataSource = (DataSource) ic.lookup("jdbc/sample");
	} catch (Exception ex) {
	    throw new EJBException("Unable to connect to database. " +
				   ex.getMessage());
	}
    } 

    /**
     * Creates a bean. Required by EJB spec.
     * @exception throws CreateException.
     */
    public void ejbCreate() throws java.rmi.RemoteException, javax.ejb.CreateException { 
    } 

    /**
     * Removes the bean. Required by EJB spec.
     */
    public void ejbRemove() { 
    } 

    /**
     * Loads the state of the bean from secondary storage. Required by EJB spec.
     */
    public void ejbActivate() { 
    } 

    /**
     * Serializes the state of the bean to secondary storage. Required by EJB spec.
     */
    public void ejbPassivate() { 
    } 

    /**
     * Required by EJB spec.
     */
    public void TopologyManager() { 
    } 


    /**
     * Allocate QAM resources for a particular CPE
     * @param cpeId customer premise equiment id
     * @return qam ip, port, tsid, rf channel
     * @exception RemoteException, SQLException
     */
     
    public QamResource allocate(String cpeId) throws java.rmi.RemoteException, SQLException {

       // get db connection from pool
       Connection conn = dataSource.getConnection();

       // get the next free port from reliable dataset (no live cache)
       PreparedStatement stmt = conn.prepareStatement("SELECT * FROM qamresources WHERE free = ? ORDER BY qamport"); // FOR UPDATE

       stmt.setQueryTimeout(QUERYTIMEOUT);
       stmt.setInt(1, 1);
       ResultSet rs = stmt.executeQuery();
       QamResource resource = null;
       if (rs.next()) {
	   resource = new QamResource(cpeId, 
				      rs.getString(2),
				      rs.getString(3),
				      rs.getString(4),
				      rs.getString(5));
       }
       rs.close();
       stmt.close();

       if (resource != null) {
	   stmt = conn.prepareStatement("UPDATE qamresources SET cpeid = ?, free = ?, timest = ? WHERE qamip = ? AND qamport = ?");
	   
	   Timestamp now = new Timestamp(System.currentTimeMillis());
	   stmt.setQueryTimeout(QUERYTIMEOUT);
	   stmt.setString(1, cpeId);
	   stmt.setInt(2, 0);
	   stmt.setTimestamp(3, now);
	   stmt.setString(4, resource.getIP());
	   stmt.setString(5, resource.getPort());
	   stmt.executeUpdate();
	   stmt.close();
       }
       conn.close();

       System.out.println("TopologyManager.allocate: reserving resource fpr cpeid " + cpeId + ": " + resource);
       return resource;
    }

    /**
     * Free QAM resources for a particular CPE
     * @param cpeId customer premise equiment id
     * @return true if ok, false if an exception occured
     * @exception RemoteException
     */
     
    public boolean release(String cpeId) throws java.rmi.RemoteException, SQLException {

	boolean status = true;

       // get db connection from pool
       Connection conn = dataSource.getConnection();

       // free the resource allocated to this cpeid
       PreparedStatement stmt = conn.prepareStatement("UPDATE qamresources SET cpeid = NULL, free = ?, timest = NULL WHERE cpeId = ?");
	   
       stmt.setQueryTimeout(QUERYTIMEOUT);
       stmt.setBoolean(1, true);
       stmt.setString(2, cpeId);
       stmt.executeUpdate();
       stmt.close();
       conn.close();

       System.out.println("TopologyManager.release: releasing resource for " + cpeId);
       return status;
    }

    /* TODO: merge allocateIpResource and allocate together to return a
     * ResourceObject instead of multiple different objects. */

    /**
     * 
     * Allocate IP resource for a particular CPE
     * @param cpeId (customer premise equipment id)
     * @return IPResource: server ip
     * @exception RemoteException
     */
    public IpResource allocateIpResource(String cpeId, String serverIp) throws RemoteException, SQLException {
       
       // get db connection from pool
       Connection conn = dataSource.getConnection();

       // get the next free port from reliable dataset (no live cache)
       PreparedStatement stmt = conn.prepareStatement("SELECT * FROM ipresourcesvod WHERE free = ? AND serverip = ? ORDER BY slotnum"); // FOR UPDATE

       stmt.setQueryTimeout(QUERYTIMEOUT);
       stmt.setInt(1, 1);
       stmt.setString(2,serverIp);
       ResultSet rs = stmt.executeQuery();
       IpResource ipResource = null;
       String slotnum = null;
       System.out.println("allocateIpResource: cpeId="+cpeId+" serverIp="+serverIp);
       if (rs.next()) {
	       ipResource = new IpResource(cpeId, serverIp);
           slotnum = rs.getString(1);
       }
       rs.close();
       stmt.close();

       if (ipResource != null) {
	   stmt = conn.prepareStatement("UPDATE ipresourcesvod SET cpeid = ?, free = ?, timest = ? WHERE slotnum = ? AND serverip = ?");
	   
	   Timestamp now = new Timestamp(System.currentTimeMillis());
	   stmt.setQueryTimeout(QUERYTIMEOUT);
	   stmt.setString(1, cpeId);
	   stmt.setInt(2, 0);
	   stmt.setTimestamp(3, now);
	   stmt.setString(4, slotnum);
       stmt.setString(5, serverIp);
	   stmt.executeUpdate();
	   stmt.close();
       }
       conn.close();

       System.out.println("TopologyManager.allocate: reserving ipresource for cpeid " + cpeId + ": " + ipResource);
       return ipResource;
    }
          
    /**
     * 
     * Releasing IP resource for a particular CPE
     * @param cpeId (customer premise equipment id)
     * @return boolean
     * @exception RemoteException
     */
    public boolean releaseIpResource(String cpeId) throws RemoteException, SQLException {
            
	   boolean status = true;

       // get db connection from pool
       Connection conn = dataSource.getConnection();

       // free the resource allocated to this cpeid
       PreparedStatement stmt = conn.prepareStatement("UPDATE ipresourcesvod SET cpeid = NULL, free = ?, timest = NULL WHERE cpeId = ?");
	   
       stmt.setQueryTimeout(QUERYTIMEOUT);
       stmt.setInt(1, 1);
       stmt.setString(2, cpeId);
       stmt.executeUpdate();
       stmt.close();
       conn.close();

       System.out.println("TopologyManager.release: releasing resource for " + cpeId);
       return status;
    }

}