server/filter/TCPReader.java

/* 
 * i-scream central monitoring system
 * http://www.i-scream.org.uk
 * Copyright (C) 2000-2002 i-scream
 * 
 * This program 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.
 * 
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

//---PACKAGE DECLARATION---
package uk.org.iscream.cms.server.filter;

//---IMPORTS---
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.server.componentmanager.*;
import uk.org.iscream.cms.server.filter.*;
import java.net.Socket;
import java.net.ServerSocket;
import java.io.OutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import uk.org.iscream.cms.util.*;

/**
 * Reads TCP Heartbeats from the host applications.
 *
 * @author  $Author: tdb $
 * @version $Id: TCPReader.java,v 1.18 2002/05/21 16:47:17 tdb Exp $
 */
class TCPReader extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.18 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Constructs a new TCPReader
     *
     * @param queue A reference to our Queue
     * @param port The port that the TCPReader will listen on
     */
    public TCPReader(int port, Queue queue) {
        // set the Thread name
        setName("filter.TCPReader");
        
        _port = port;
        _queue = queue;
        _logger.write(toString(), Logger.SYSINIT, "started");
    }

    

//---PUBLIC METHODS---

    /**
     * The run() method is the main loop for this thread, and we
     * will remain in here until such a point as something goes
     * wrong with the listening. After initially setting up the
     * ServerSocket we go round a while loop receiving connections
     * and then passing them off to other processes to deal with.
     */
    public void run(){
        // setup an empty ACL defaulting to ALLOW
        ACL acl = new ACL(ACL.ALLOW);
        
        // Setup the ServerSocket so that clients can connect
        ServerSocket listenPort=null;
        try{
            listenPort = new ACLServerSocket(acl, _port);
        }
        catch(IOException e){
            _logger.write(toString(), Logger.FATAL, "Failed to setup ServerSocket: " + e);
            return;
        }
        
        // Log what machine/port we're listening on
        try{
            _logger.write(toString(), Logger.SYSMSG, "TCPReader listening on "
                                        +InetAddress.getLocalHost().getHostName()
                                        +"/"+InetAddress.getLocalHost().getHostAddress()
                                        +" port "+listenPort.getLocalPort());
        }
        catch(UnknownHostException e){
            _logger.write(toString(), Logger.SYSMSG, "TCPReader listening on UnknownHost "
                                        +"port "+listenPort.getLocalPort());
        }
        
        // We use this boolean so we can break out of the while loop if we want
        boolean run = true;
        
        // Loop round constantly until we decide to stop
        ConfigurationProxy cp = ConfigurationProxy.getInstance();
        String stringACL = "";
        String newStringACL = "";
        while(run){
            // get hold of the ACL in the configuration
            try {
                newStringACL = cp.getProperty("Filter." + FilterMain.NAME, "Filter.TCPACL");
            }
            catch(PropertyNotFoundException e) {
                // if we can't find it, we'll just use a null ACL
                newStringACL = "";
                _logger.write(toString(), Logger.WARNING, "No ACL found for TCPReader, using empty ACL instead: " + e);
            }
            // check to see if the ACL has changed
            if(!newStringACL.equals(stringACL)) {
                _logger.write(toString(), Logger.SYSMSG, "Reloading Access Control List");
                // clear the ACL
                acl.clear();
                // set the default to something sane
                acl.setDefaultMode(ACL.ALLOW);
                // add the new ACL (this may change the default)
                acl.add(newStringACL);
                stringACL = newStringACL;
            }
            Socket hostSocket=null;
            try{
                _logger.write(toString(), Logger.DEBUG, "Waiting for Connection");
                // This will block until a host connects - at which point we get a Socket
                hostSocket = listenPort.accept();
                _logger.write(toString(), Logger.DEBUG, "Connection accepted from: " + hostSocket.toString());
            }
            catch(IOException e){
                // Something went wrong with the ServerSocket, so we'll stop listening
                run=false;
            }
            // If we've stopped on the line above we won't want to try this !
            if(run){
                try {
                    // Setup the TCPReaderInit and start it
                    TCPReaderInit init = new TCPReaderInit(hostSocket, _queue);
                    // and start it
                    init.start();
                } catch (IOException e) {
                    _logger.write(toString(), Logger.ERROR, e.toString());
                }
            }
        }
        // Best log the fact that we're stopping
        _logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
    }

    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.org.iscream.cms.util.NameFormat class
     * to format the toString()
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return FormatName.getName(
            _name,
            getClass().getName(),
            REVISION);
    }

//---PRIVATE METHODS---

//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---
    
    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    private String _name = FilterMain.NAME;

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
     * The port on which the server should listen.
     */
    private int _port;
    
    /**
     * A reference to our Queue
     */
    private Queue _queue;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.19
Committed:	Wed Feb 5 16:43:47 2003 UTC (21 years, 3 months ago) by tdb
Branch:	MAIN
Changes since 1.18:	+4 -4 lines
Log Message:	Changed the server to use the external util package. Quite a minor change, but does affect a lot of files.
#	User	Rev	Content
1	tdb	1.17	/*
2			* i-scream central monitoring system
3	tdb	1.18	* http://www.i-scream.org.uk
4	tdb	1.17	* Copyright (C) 2000-2002 i-scream
5			*
6			* This program is free software; you can redistribute it and/or
7			* modify it under the terms of the GNU General Public License
8			* as published by the Free Software Foundation; either version 2
9			* of the License, or (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19			*/
20
21	tdb	1.1	//---PACKAGE DECLARATION---
22	tdb	1.12	package uk.org.iscream.cms.server.filter;
23	tdb	1.1
24			//---IMPORTS---
25	tdb	1.12	import uk.org.iscream.cms.server.core.*;
26			import uk.org.iscream.cms.server.componentmanager.*;
27			import uk.org.iscream.cms.server.filter.*;
28	tdb	1.1	import java.net.Socket;
29			import java.net.ServerSocket;
30			import java.io.OutputStream;
31			import java.io.IOException;
32			import java.net.InetAddress;
33			import java.net.UnknownHostException;
34	tdb	1.19	import uk.org.iscream.cms.util.*;
35	tdb	1.1
36			/**
37	tdb	1.8	* Reads TCP Heartbeats from the host applications.
38	tdb	1.1	*
39	tdb	1.13	* @author $Author: tdb $
40	tdb	1.19	* @version $Id: TCPReader.java,v 1.18 2002/05/21 16:47:17 tdb Exp $
41	tdb	1.1	*/
42			class TCPReader extends Thread {
43
44			//---FINAL ATTRIBUTES---
45
46			/**
47			* The current CVS revision of this class
48			*/
49	tdb	1.19	public final String REVISION = "$Revision: 1.18 $";
50	tdb	1.1
51			//---STATIC METHODS---
52
53			//---CONSTRUCTORS---
54
55	tdb	1.16	/**
56	tdb	1.8	* Constructs a new TCPReader
57	tdb	1.1	*
58	tdb	1.8	* @param queue A reference to our Queue
59	tdb	1.16	* @param port The port that the TCPReader will listen on
60			*/
61	tdb	1.6	public TCPReader(int port, Queue queue) {
62	tdb	1.10	// set the Thread name
63			setName("filter.TCPReader");
64
65	tdb	1.1	_port = port;
66	tdb	1.6	_queue = queue;
67	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "started");
68			}
69
70
71
72			//---PUBLIC METHODS---
73
74	tdb	1.16	/**
75			* The run() method is the main loop for this thread, and we
76			* will remain in here until such a point as something goes
77			* wrong with the listening. After initially setting up the
78			* ServerSocket we go round a while loop receiving connections
79			* and then passing them off to other processes to deal with.
80			*/
81	tdb	1.1	public void run(){
82	tdb	1.16	// setup an empty ACL defaulting to ALLOW
83			ACL acl = new ACL(ACL.ALLOW);
84
85			// Setup the ServerSocket so that clients can connect
86			ServerSocket listenPort=null;
87			try{
88			listenPort = new ACLServerSocket(acl, _port);
89	tdb	1.13	}
90	tdb	1.16	catch(IOException e){
91			_logger.write(toString(), Logger.FATAL, "Failed to setup ServerSocket: " + e);
92			return;
93	tdb	1.13	}
94	tdb	1.16
95			// Log what machine/port we're listening on
96	tdb	1.1	try{
97	tdb	1.16	_logger.write(toString(), Logger.SYSMSG, "TCPReader listening on "
98			+InetAddress.getLocalHost().getHostName()
99			+"/"+InetAddress.getLocalHost().getHostAddress()
100			+" port "+listenPort.getLocalPort());
101	tdb	1.1	}
102	tdb	1.16	catch(UnknownHostException e){
103			_logger.write(toString(), Logger.SYSMSG, "TCPReader listening on UnknownHost "
104			+"port "+listenPort.getLocalPort());
105	tdb	1.1	}
106	tdb	1.13
107	tdb	1.16	// We use this boolean so we can break out of the while loop if we want
108	tdb	1.13	boolean run = true;
109	tdb	1.16
110			// Loop round constantly until we decide to stop
111			ConfigurationProxy cp = ConfigurationProxy.getInstance();
112			String stringACL = "";
113			String newStringACL = "";
114	tdb	1.1	while(run){
115	tdb	1.16	// get hold of the ACL in the configuration
116			try {
117			newStringACL = cp.getProperty("Filter." + FilterMain.NAME, "Filter.TCPACL");
118			}
119			catch(PropertyNotFoundException e) {
120			// if we can't find it, we'll just use a null ACL
121			newStringACL = "";
122			_logger.write(toString(), Logger.WARNING, "No ACL found for TCPReader, using empty ACL instead: " + e);
123			}
124			// check to see if the ACL has changed
125			if(!newStringACL.equals(stringACL)) {
126			_logger.write(toString(), Logger.SYSMSG, "Reloading Access Control List");
127			// clear the ACL
128			acl.clear();
129			// set the default to something sane
130			acl.setDefaultMode(ACL.ALLOW);
131			// add the new ACL (this may change the default)
132			acl.add(newStringACL);
133			stringACL = newStringACL;
134			}
135			Socket hostSocket=null;
136	tdb	1.1	try{
137	tdb	1.9	_logger.write(toString(), Logger.DEBUG, "Waiting for Connection");
138	tdb	1.16	// This will block until a host connects - at which point we get a Socket
139	tdb	1.1	hostSocket = listenPort.accept();
140	tdb	1.9	_logger.write(toString(), Logger.DEBUG, "Connection accepted from: " + hostSocket.toString());
141	tdb	1.1	}
142			catch(IOException e){
143	tdb	1.16	// Something went wrong with the ServerSocket, so we'll stop listening
144	tdb	1.1	run=false;
145			}
146	tdb	1.16	// If we've stopped on the line above we won't want to try this !
147	tdb	1.1	if(run){
148	tdb	1.16	try {
149			// Setup the TCPReaderInit and start it
150	tdb	1.6	TCPReaderInit init = new TCPReaderInit(hostSocket, _queue);
151	tdb	1.16	// and start it
152	tdb	1.1	init.start();
153			} catch (IOException e) {
154			_logger.write(toString(), Logger.ERROR, e.toString());
155			}
156			}
157			}
158	tdb	1.16	// Best log the fact that we're stopping
159	tdb	1.1	_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
160			}
161
162			/**
163			* Overrides the {@link java.lang.Object#toString() Object.toString()}
164			* method to provide clean logging (every class should have this).
165			*
166	tdb	1.19	* This uses the uk.org.iscream.cms.util.NameFormat class
167	ajm	1.5	* to format the toString()
168			*
169	tdb	1.1	* @return the name of this class and its CVS revision
170			*/
171			public String toString() {
172	ajm	1.5	return FormatName.getName(
173			_name,
174			getClass().getName(),
175			REVISION);
176	tdb	1.1	}
177
178			//---PRIVATE METHODS---
179
180			//---ACCESSOR/MUTATOR METHODS---
181
182			//---ATTRIBUTES---
183
184			/**
185	ajm	1.5	* This is the friendly identifier of the
186			* component this class is running in.
187			* eg, a Filter may be called "filter1",
188			* If this class does not have an owning
189			* component, a name from the configuration
190			* can be placed here. This name could also
191			* be changed to null for utility classes.
192			*/
193			private String _name = FilterMain.NAME;
194
195			/**
196			* This holds a reference to the
197			* system logger that is being used.
198	tdb	1.1	*/
199	ajm	1.5	private Logger _logger = ReferenceManager.getInstance().getLogger();
200	tdb	1.1
201			/**
202	tdb	1.16	* The port on which the server should listen.
203			*/
204	tdb	1.1	private int _port;
205
206	tdb	1.8	/**
207			* A reference to our Queue
208			*/
209	tdb	1.6	private Queue _queue;
210	tdb	1.1
211			//---STATIC ATTRIBUTES---
212
213			}