server/filtermanager/HostInit.java

//---PACKAGE DECLARATION---
package uk.ac.ukc.iscream.filtermanager;

//---IMPORTS---
import uk.ac.ukc.iscream.core.*;
import uk.ac.ukc.iscream.filter.*;
import uk.ac.ukc.iscream.util.*;
import uk.ac.ukc.iscream.componentmanager.*;
import java.net.*;
import java.io.*;
import java.util.*;

/**
 * Handles setting up a host.
 * This class provides a host with appropriate configuration
 * and a reference to a Filter to which it should pass data.
 *
 * @author  $Author: tdb1 $
 * @version $Id: HostInit.java,v 1.25 2001/03/13 02:19:47 tdb1 Exp $
 */
class HostInit extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.25 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Construct a new HostInit.
     *
     * @param socket The socket to which the host is connected
     */
    public HostInit(Socket socket) throws IOException {
        // set the Thread name
        setName("filtermanager.HostInit");
        
        _socket = socket;
        // setup reader & writer
        _socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
        _socketOut = new PrintWriter(_socket.getOutputStream(), true);
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---

    /**
     * Main method in this class, which handles communicating with
     * the host to determine it's setup.
     */
    public void run() {
        // get a hook on the config proxy
        ConfigurationProxy cp = ConfigurationProxy.getInstance();
        // this is our config name
        String configName = "Host." + _socket.getInetAddress().getHostName().toLowerCase();
        try {
            // try for STARTCONFIG
            getInBound("STARTCONFIG");
            _socketOut.println("OK");
            
            // try for LASTMODIFIED
            getInBound("LASTMODIFIED");
            _socketOut.println(cp.getLastModified(configName));
            
            // try for FILELIST
            getInBound("FILELIST");
            _socketOut.println(cp.getFileList(configName));
            
            // try for FQDN
            getInBound("FQDN");
            _socketOut.println(_socket.getInetAddress().getHostName().toLowerCase());
            
            // get properties
            String reqProperty = getInBound();
            while(!reqProperty.equals("ENDCONFIG")) {
                // get the property
                try {
                    String returnedProperty = cp.getProperty(configName, "Host."+reqProperty);
                    _socketOut.println(returnedProperty);
                } catch (PropertyNotFoundException e) {
                    _socketOut.println("ERROR");
                }
                // get the next request
                reqProperty = _socketIn.readLine();
            }
            _logger.write(toString(), Logger.SYSMSG, "configured host");
            _socketOut.println("OK");
            
            // get filter reference
            getInBound("FILTER");
                // send info
                String filterList = cp.getProperty(configName, "Host.filter");
                Filter filterRef = null;
                String filter = null;
                StringTokenizer st = new StringTokenizer(filterList, ";");
            while (filterRef==null && st.hasMoreTokens()) {
                filter = st.nextToken();
                _logger.write(toString(), Logger.DEBUG, " looking for filter- " + filter);
                try {
                    filterRef = FilterHelper.narrow(ReferenceManager.getInstance().getCORBARef("iscream.Filter." + filter));
                } catch (ComponentCORBAException e) {
                    _logger.write(toString(), Logger.DEBUG, " unable to find filter- " + filter);
                }
            }
                
                // hopefully we found a filter
            if(filterRef != null) {
                _logger.write(toString(), Logger.DEBUG, " found filter- " + filter);
                // tell the host about it...
                    _socketOut.println(filterRef.getHostName() + ";"
                                     + filterRef.getUDPPort() + ";"
                                     + filterRef.getTCPPort());
                }
                else {
                    // ...or throw a wobbly (and tell the host!)
                    _socketOut.println("ERROR");
                    throw new IOException("unable to find filter for host");
                }
            
            // confirm ok with END
            getInBound("END");
            _socketOut.println("OK");
            
        } catch (Exception e) {
            _logger.write(toString(), Logger.ERROR, "ERROR - " + e);
        }
        
        // Disconnect streams & socket
        try {
            _socketIn.close();
            _socketOut.close();
            _socket.close();
        } catch (IOException e) {
            _logger.write(toString(), Logger.ERROR, "exception on socket close");
        }
        _logger.write(toString(), Logger.SYSMSG, "finished");
    }
    
    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.ac.ukc.iscream.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---

    private String getInBound(String expected) throws IOException {
        // grab the input
        String inBound = getInBound();
        // check if it's what we're expecting
        if(!inBound.equals(expected)) {
            throw new IOException("protocol error - expected:"+expected+" got:" + inBound);
        }
        // it should be ok then
        return inBound;
    }
    
    private String getInBound() throws IOException {
        // grab the input
        String inBound = _socketIn.readLine();
        // check for null's, likely disconnection
        if(inBound == null) {
            throw new IOException("got null from host, maybe it died");
        }
        // it's a valid message it seems
        return inBound;
    }

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

//---ATTRIBUTES---

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
     * A reference to the Configuration Manager the system is using
     */
    private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
    
    /**
     * 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 = FilterManager.NAME;
    
    /** 
     * The socket this class uses
     */
    private Socket _socket;

    /**
     * Used for the input stream of this socket
     */
    private BufferedReader _socketIn;
    
    /**
     * Used for the output stream of this socket
     */
    private PrintWriter _socketOut;

//---STATIC ATTRIBUTES---

}
Revision:	1.26
Committed:	Tue Mar 13 13:40:26 2001 UTC (23 years, 2 months ago) by tdb
Branch:	MAIN
Changes since 1.25:	+90 -117 lines
Log Message:	Added support for the ConfigurationProxy. Also made the HostInit more "safe", with checking for null's from the host.
#	User	Rev	Content
1	tdb	1.1	//---PACKAGE DECLARATION---
2	tdb	1.9	package uk.ac.ukc.iscream.filtermanager;
3	tdb	1.1
4			//---IMPORTS---
5			import uk.ac.ukc.iscream.core.*;
6	tdb	1.7	import uk.ac.ukc.iscream.filter.*;
7	tdb	1.11	import uk.ac.ukc.iscream.util.*;
8	tdb	1.14	import uk.ac.ukc.iscream.componentmanager.*;
9	tdb	1.18	import java.net.*;
10	tdb	1.1	import java.io.*;
11	tdb	1.22	import java.util.*;
12	tdb	1.1
13			/**
14	tdb	1.11	* Handles setting up a host.
15	ajm	1.12	* This class provides a host with appropriate configuration
16			* and a reference to a Filter to which it should pass data.
17	tdb	1.1	*
18	tdb	1.15	* @author $Author: tdb1 $
19	tdb	1.26	* @version $Id: HostInit.java,v 1.25 2001/03/13 02:19:47 tdb1 Exp $
20	tdb	1.1	*/
21			class HostInit extends Thread {
22
23			//---FINAL ATTRIBUTES---
24
25			/**
26			* The current CVS revision of this class
27			*/
28	tdb	1.26	public final String REVISION = "$Revision: 1.25 $";
29	tdb	1.1
30			//---STATIC METHODS---
31
32			//---CONSTRUCTORS---
33
34	tdb	1.15	/**
35			* Construct a new HostInit.
36			*
37			* @param socket The socket to which the host is connected
38			*/
39	tdb	1.11	public HostInit(Socket socket) throws IOException {
40	tdb	1.25	// set the Thread name
41			setName("filtermanager.HostInit");
42
43	tdb	1.1	_socket = socket;
44	tdb	1.15	// setup reader & writer
45	tdb	1.1	_socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
46	tdb	1.16	_socketOut = new PrintWriter(_socket.getOutputStream(), true);
47	tdb	1.11	_logger.write(toString(), Logger.SYSINIT, "created");
48	tdb	1.1	}
49
50			//---PUBLIC METHODS---
51
52	tdb	1.15	/**
53			* Main method in this class, which handles communicating with
54			* the host to determine it's setup.
55			*/
56	tdb	1.1	public void run() {
57	tdb	1.26	// get a hook on the config proxy
58			ConfigurationProxy cp = ConfigurationProxy.getInstance();
59			// this is our config name
60			String configName = "Host." + _socket.getInetAddress().getHostName().toLowerCase();
61	tdb	1.1	try {
62	tdb	1.26	// try for STARTCONFIG
63			getInBound("STARTCONFIG");
64			_socketOut.println("OK");
65
66			// try for LASTMODIFIED
67			getInBound("LASTMODIFIED");
68			_socketOut.println(cp.getLastModified(configName));
69
70			// try for FILELIST
71			getInBound("FILELIST");
72			_socketOut.println(cp.getFileList(configName));
73
74			// try for FQDN
75			getInBound("FQDN");
76			_socketOut.println(_socket.getInetAddress().getHostName().toLowerCase());
77
78			// get properties
79			String reqProperty = getInBound();
80			while(!reqProperty.equals("ENDCONFIG")) {
81			// get the property
82			try {
83			String returnedProperty = cp.getProperty(configName, "Host."+reqProperty);
84			_socketOut.println(returnedProperty);
85			} catch (PropertyNotFoundException e) {
86	tdb	1.2	_socketOut.println("ERROR");
87	tdb	1.4	}
88	tdb	1.26	// get the next request
89			reqProperty = _socketIn.readLine();
90			}
91			_logger.write(toString(), Logger.SYSMSG, "configured host");
92			_socketOut.println("OK");
93
94			// get filter reference
95			getInBound("FILTER");
96			// send info
97			String filterList = cp.getProperty(configName, "Host.filter");
98			Filter filterRef = null;
99			String filter = null;
100			StringTokenizer st = new StringTokenizer(filterList, ";");
101			while (filterRef==null && st.hasMoreTokens()) {
102			filter = st.nextToken();
103			_logger.write(toString(), Logger.DEBUG, " looking for filter- " + filter);
104			try {
105			filterRef = FilterHelper.narrow(ReferenceManager.getInstance().getCORBARef("iscream.Filter." + filter));
106			} catch (ComponentCORBAException e) {
107			_logger.write(toString(), Logger.DEBUG, " unable to find filter- " + filter);
108	tdb	1.7	}
109	tdb	1.1	}
110	tdb	1.26
111			// hopefully we found a filter
112			if(filterRef != null) {
113			_logger.write(toString(), Logger.DEBUG, " found filter- " + filter);
114			// tell the host about it...
115			_socketOut.println(filterRef.getHostName() + ";"
116			+ filterRef.getUDPPort() + ";"
117			+ filterRef.getTCPPort());
118			}
119			else {
120			// ...or throw a wobbly (and tell the host!)
121			_socketOut.println("ERROR");
122			throw new IOException("unable to find filter for host");
123			}
124
125			// confirm ok with END
126			getInBound("END");
127			_socketOut.println("OK");
128	tdb	1.1
129			} catch (Exception e) {
130	tdb	1.17	_logger.write(toString(), Logger.ERROR, "ERROR - " + e);
131	tdb	1.1	}
132
133			// Disconnect streams & socket
134			try {
135			_socketIn.close();
136			_socketOut.close();
137			_socket.close();
138			} catch (IOException e) {
139	tdb	1.11	_logger.write(toString(), Logger.ERROR, "exception on socket close");
140	tdb	1.1	}
141	tdb	1.11	_logger.write(toString(), Logger.SYSMSG, "finished");
142	tdb	1.1	}
143
144			/**
145			* Overrides the {@link java.lang.Object#toString() Object.toString()}
146			* method to provide clean logging (every class should have this).
147			*
148	ajm	1.12	* This uses the uk.ac.ukc.iscream.util.NameFormat class
149			* to format the toString()
150			*
151	tdb	1.1	* @return the name of this class and its CVS revision
152			*/
153			public String toString() {
154	ajm	1.12	return FormatName.getName(
155			_name,
156	ajm	1.13	getClass().getName(),
157	ajm	1.12	REVISION);
158	tdb	1.1	}
159
160			//---PRIVATE METHODS---
161	tdb	1.26
162			private String getInBound(String expected) throws IOException {
163			// grab the input
164			String inBound = getInBound();
165			// check if it's what we're expecting
166			if(!inBound.equals(expected)) {
167			throw new IOException("protocol error - expected:"+expected+" got:" + inBound);
168			}
169			// it should be ok then
170			return inBound;
171			}
172
173			private String getInBound() throws IOException {
174			// grab the input
175			String inBound = _socketIn.readLine();
176			// check for null's, likely disconnection
177			if(inBound == null) {
178			throw new IOException("got null from host, maybe it died");
179			}
180			// it's a valid message it seems
181			return inBound;
182			}
183	tdb	1.1
184			//---ACCESSOR/MUTATOR METHODS---
185
186			//---ATTRIBUTES---
187
188	tdb	1.11	/**
189	ajm	1.12	* This holds a reference to the
190			* system logger that is being used.
191	tdb	1.11	*/
192	ajm	1.12	private Logger _logger = ReferenceManager.getInstance().getLogger();
193	tdb	1.11
194			/**
195			* A reference to the Configuration Manager the system is using
196			*/
197	ajm	1.12	private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
198
199			/**
200			* This is the friendly identifier of the
201			* component this class is running in.
202			* eg, a Filter may be called "filter1",
203			* If this class does not have an owning
204			* component, a name from the configuration
205			* can be placed here. This name could also
206			* be changed to null for utility classes.
207			*/
208			private String _name = FilterManager.NAME;
209
210			/**
211			* The socket this class uses
212			*/
213			private Socket _socket;
214
215			/**
216			* Used for the input stream of this socket
217			*/
218			private BufferedReader _socketIn;
219	tdb	1.11
220	ajm	1.12	/**
221			* Used for the output stream of this socket
222			*/
223			private PrintWriter _socketOut;
224	tdb	1.11
225	tdb	1.1	//---STATIC ATTRIBUTES---
226
227			}