cms/conient/Configuration.java

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

//---IMPORTS---
import javax.swing.JOptionPane;
import java.util.Properties;
import java.io.*;

/**
 * Provides configuration details to Conient
 * This class is a Singleton class and
 *
 * @author  $Author: ajm4 $
 * @version $Id: Configuration.java,v 1.3 2001/02/04 23:45:10 ajm4 Exp $
 */
public class Configuration {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.3 $";
    
//---STATIC METHODS---

    /**
     * Creates and initialises a the Configuration
     * system for Conient.  This calls the private
     * constructor and ensures this class is a singleton.
     *
     * @param configFile the path to the file that this configuration should load
     */
    public static void initialise(String configFile) {
        _instance = new Configuration(configFile);
    }

    /**
     * Returns the singleton instance of this
     * class.
     * This will throw a runtime exception if it 
     * is called at the wrong time!
     *
     * @return the singleton instance
     */
    public static Configuration getInstance() {
        if (_instance == null) {
            throw new RuntimeException("Configuration class requested but HASN'T been initialised!");
        }
        return _instance;
    }

//---CONSTRUCTORS---

    /**
     * The private constructor, ensures that this is a singleton.
     * Simply reads in the local configuration from the file.
     * Then sets the current properties to be this configuration.
     * Later the system will obtain further configuration from the
     * server.
     *
     * @param configFile the path to the file that this configuration should load
     */
    private Configuration(String configFile) {
        try {
            _properties = readFileConfiguration(configFile);
        } catch (FileNotFoundException e) {
            JOptionPane.showMessageDialog(null, "Configuration file not found - " + configFile, "Configuration Error", JOptionPane.ERROR_MESSAGE);
            System.exit(1);
        } catch (IOException e) {
            JOptionPane.showMessageDialog(null, "Unable to read configuration file - " + e.getMessage(), "Configuration Error", JOptionPane.ERROR_MESSAGE);
            System.exit(1);
        }
    }

//---PUBLIC METHODS---

    /**
     * This routine asks the server for all configuration
     * options that are needed to be obtained from the
     * server.  It takes hooks to the I/O streams for the
     * control link socket in order that it can request
     * the attributes.  It is assumed that the connection 
     * has been negotiated to a stage that the server is
     * ready to server attributes.  Once this method returns
     * the calling class should tell the server that configuration
     * has terminated.
     *
     * @param in the input stream of the control link
     * @param out the output stream of the control link
     * @throws IOException if there is an error communicating
     */
    public void readServerConfiguration(BufferedReader in, PrintWriter out) throws IOException {
        String response = null;
        out.println("Host.UDPUpdateTime");
        out.flush();
        response = in.readLine();
        
        if (!response.equals("ERROR")) {
            _properties.setProperty("Host.UDPUpdateTime", response);
        }
        out.println("Host.TCPUpdateTime");
        out.flush();
        response = in.readLine();
        
        if (!response.equals("ERROR")) {
            _properties.setProperty("Host.TCPUpdateTime", response);
        }
    }
    
    /**
     * Tells the configuration class that it should
     * perform user re-configuration through displaying
     * a gui.  This passes control to a dialog to 
     * handle re-configuration.  Basically this is
     * the nicer alternative to hacking the config
     * file.
     * The ConientConfiguration class is responsible
     * for handling the re-configuration.
     */
    public void GUIReconfiguration() {
        //ConientConfiguration conf = new ConientConfiguration();
    }
//---PRIVATE METHODS---

    /**
     * Reads in the specified file and parses
     * its properties.
     *
     * @param configFile the path of the file to be read
     * @return the parsed properties
     */
    private Properties readFileConfiguration(String configFile) throws FileNotFoundException, IOException {
        File file = new File(configFile);
        Properties configHolder = new Properties();
        configHolder.load(new FileInputStream(file));
        return configHolder;
    }

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

    /**
     * A wrapper for java.util.Properties.getProperty
     * When given a key it returns the value of that key
     * ie, key = value
     *
     * @param key the key the value of which is wanted
     */
    public String getProperty(String key) {
        return _properties.getProperty(key); 
    }

//---ATTRIBUTES---

    /**
     * The current configuration in use
     */
    private Properties _properties = null;

//---STATIC ATTRIBUTES---

    /**
     * The reference to the singleton instance of this class
     */
    private static Configuration _instance = null;
}
Revision:	1.4
Committed:	Fri Feb 16 16:24:08 2001 UTC (23 years, 3 months ago) by ajm
Branch:	MAIN
Changes since 1.3:	+30 -2 lines
Log Message:	An extra bit of javadoc, and now has the start of support for GUI config
#	User	Rev	Content
1	ajm	1.1	//---PACKAGE DECLARATION---
2			package uk.ac.ukc.iscream.conient;
3
4			//---IMPORTS---
5	ajm	1.3	import javax.swing.JOptionPane;
6	ajm	1.1	import java.util.Properties;
7	ajm	1.2	import java.io.*;
8	ajm	1.1
9			/**
10			* Provides configuration details to Conient
11			* This class is a Singleton class and
12			*
13	ajm	1.2	* @author $Author: ajm4 $
14	ajm	1.4	* @version $Id: Configuration.java,v 1.3 2001/02/04 23:45:10 ajm4 Exp $
15	ajm	1.1	*/
16			public class Configuration {
17
18			//---FINAL ATTRIBUTES---
19
20			/**
21			* The current CVS revision of this class
22			*/
23	ajm	1.4	public static final String REVISION = "$Revision: 1.3 $";
24	ajm	1.1
25			//---STATIC METHODS---
26
27			/**
28			* Creates and initialises a the Configuration
29			* system for Conient. This calls the private
30			* constructor and ensures this class is a singleton.
31			*
32			* @param configFile the path to the file that this configuration should load
33			*/
34			public static void initialise(String configFile) {
35			_instance = new Configuration(configFile);
36			}
37
38			/**
39			* Returns the singleton instance of this
40			* class.
41			* This will throw a runtime exception if it
42			* is called at the wrong time!
43			*
44			* @return the singleton instance
45			*/
46			public static Configuration getInstance() {
47			if (_instance == null) {
48			throw new RuntimeException("Configuration class requested but HASN'T been initialised!");
49			}
50			return _instance;
51			}
52
53			//---CONSTRUCTORS---
54
55			/**
56			* The private constructor, ensures that this is a singleton.
57			* Simply reads in the local configuration from the file.
58			* Then sets the current properties to be this configuration.
59			* Later the system will obtain further configuration from the
60			* server.
61			*
62			* @param configFile the path to the file that this configuration should load
63			*/
64			private Configuration(String configFile) {
65			try {
66			_properties = readFileConfiguration(configFile);
67			} catch (FileNotFoundException e) {
68	ajm	1.3	JOptionPane.showMessageDialog(null, "Configuration file not found - " + configFile, "Configuration Error", JOptionPane.ERROR_MESSAGE);
69			System.exit(1);
70	ajm	1.1	} catch (IOException e) {
71	ajm	1.3	JOptionPane.showMessageDialog(null, "Unable to read configuration file - " + e.getMessage(), "Configuration Error", JOptionPane.ERROR_MESSAGE);
72			System.exit(1);
73	ajm	1.1	}
74			}
75
76			//---PUBLIC METHODS---
77
78	ajm	1.4	/**
79			* This routine asks the server for all configuration
80			* options that are needed to be obtained from the
81			* server. It takes hooks to the I/O streams for the
82			* control link socket in order that it can request
83			* the attributes. It is assumed that the connection
84			* has been negotiated to a stage that the server is
85			* ready to server attributes. Once this method returns
86			* the calling class should tell the server that configuration
87			* has terminated.
88			*
89			* @param in the input stream of the control link
90			* @param out the output stream of the control link
91			* @throws IOException if there is an error communicating
92			*/
93	ajm	1.2	public void readServerConfiguration(BufferedReader in, PrintWriter out) throws IOException {
94			String response = null;
95			out.println("Host.UDPUpdateTime");
96			out.flush();
97			response = in.readLine();
98
99			if (!response.equals("ERROR")) {
100			_properties.setProperty("Host.UDPUpdateTime", response);
101			}
102			out.println("Host.TCPUpdateTime");
103			out.flush();
104			response = in.readLine();
105
106			if (!response.equals("ERROR")) {
107			_properties.setProperty("Host.TCPUpdateTime", response);
108			}
109			}
110
111	ajm	1.4	/**
112			* Tells the configuration class that it should
113			* perform user re-configuration through displaying
114			* a gui. This passes control to a dialog to
115			* handle re-configuration. Basically this is
116			* the nicer alternative to hacking the config
117			* file.
118			* The ConientConfiguration class is responsible
119			* for handling the re-configuration.
120			*/
121			public void GUIReconfiguration() {
122			//ConientConfiguration conf = new ConientConfiguration();
123			}
124	ajm	1.1	//---PRIVATE METHODS---
125
126			/**
127			* Reads in the specified file and parses
128			* its properties.
129			*
130			* @param configFile the path of the file to be read
131			* @return the parsed properties
132			*/
133			private Properties readFileConfiguration(String configFile) throws FileNotFoundException, IOException {
134			File file = new File(configFile);
135			Properties configHolder = new Properties();
136			configHolder.load(new FileInputStream(file));
137			return configHolder;
138			}
139
140			//---ACCESSOR/MUTATOR METHODS---
141
142			/**
143			* A wrapper for java.util.Properties.getProperty
144			* When given a key it returns the value of that key
145			* ie, key = value
146			*
147			* @param key the key the value of which is wanted
148			*/
149			public String getProperty(String key) {
150			return _properties.getProperty(key);
151			}
152
153			//---ATTRIBUTES---
154
155			/**
156			* The current configuration in use
157			*/
158			private Properties _properties = null;
159
160			//---STATIC ATTRIBUTES---
161
162			/**
163			* The reference to the singleton instance of this class
164			*/
165			private static Configuration _instance = null;
166			}