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 1.2 2001/02/03 19:17:38 ajm4 Exp $
 */
public class Configuration {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.2 $";
    
//---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---

    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);
        }
    }
    
//---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:	1.3
Committed:	Sun Feb 4 23:45:10 2001 UTC (23 years, 4 months ago) by ajm
Branch:	MAIN
Changes since 1.2:	+7 -6 lines
Log Message:	now shows an error in a window rather than just on the console....
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.ac.ukc.iscream.conient;
3
4	//---IMPORTS---
5	import javax.swing.JOptionPane;
6	import java.util.Properties;
7	import java.io.*;
8
9	/**
10	* Provides configuration details to Conient
11	* This class is a Singleton class and
12	*
13	* @author $Author: ajm4 $
14	* @version $Id: Configuration.java,v 1.2 2001/02/03 19:17:38 ajm4 Exp $
15	*/
16	public class Configuration {
17
18	//---FINAL ATTRIBUTES---
19
20	/**
21	* The current CVS revision of this class
22	*/
23	public static final String REVISION = "$Revision: 1.2 $";
24
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	JOptionPane.showMessageDialog(null, "Configuration file not found - " + configFile, "Configuration Error", JOptionPane.ERROR_MESSAGE);
69	System.exit(1);
70	} catch (IOException e) {
71	JOptionPane.showMessageDialog(null, "Unable to read configuration file - " + e.getMessage(), "Configuration Error", JOptionPane.ERROR_MESSAGE);
72	System.exit(1);
73	}
74	}
75
76	//---PUBLIC METHODS---
77
78	public void readServerConfiguration(BufferedReader in, PrintWriter out) throws IOException {
79	String response = null;
80	out.println("Host.UDPUpdateTime");
81	out.flush();
82	response = in.readLine();
83
84	if (!response.equals("ERROR")) {
85	_properties.setProperty("Host.UDPUpdateTime", response);
86	}
87	out.println("Host.TCPUpdateTime");
88	out.flush();
89	response = in.readLine();
90
91	if (!response.equals("ERROR")) {
92	_properties.setProperty("Host.TCPUpdateTime", response);
93	}
94	}
95
96	//---PRIVATE METHODS---
97
98	/**
99	* Reads in the specified file and parses
100	* its properties.
101	*
102	* @param configFile the path of the file to be read
103	* @return the parsed properties
104	*/
105	private Properties readFileConfiguration(String configFile) throws FileNotFoundException, IOException {
106	File file = new File(configFile);
107	Properties configHolder = new Properties();
108	configHolder.load(new FileInputStream(file));
109	return configHolder;
110	}
111
112	//---ACCESSOR/MUTATOR METHODS---
113
114	/**
115	* A wrapper for java.util.Properties.getProperty
116	* When given a key it returns the value of that key
117	* ie, key = value
118	*
119	* @param key the key the value of which is wanted
120	*/
121	public String getProperty(String key) {
122	return _properties.getProperty(key);
123	}
124
125	//---ATTRIBUTES---
126
127	/**
128	* The current configuration in use
129	*/
130	private Properties _properties = null;
131
132	//---STATIC ATTRIBUTES---
133
134	/**
135	* The reference to the singleton instance of this class
136	*/
137	private static Configuration _instance = null;
138	}