cms/conient/Configuration.java

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

//---IMPORTS---
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 1.1 2001/01/30 02:13:34 ajm4 Exp $
 */
public class Configuration {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.1 $";
    
//---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) {
            // should show a box!
            System.err.println("ERROR{configuration}: file not found - " + e.getMessage());
        } catch (IOException e) {
            // should show a box!
            System.err.println("ERROR{configuration}: i/o error - " + e.getMessage());
        }
    }

//---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:	1.2
Committed:	Sat Feb 3 19:17:38 2001 UTC (23 years, 3 months ago) by ajm
Branch:	MAIN
Changes since 1.1:	+22 -7 lines
Log Message:	ConnectionHandler can now ask this class to obtain a configuaration over the control link.
#	User	Rev	Content
1	ajm	1.1	//---PACKAGE DECLARATION---
2			package uk.ac.ukc.iscream.conient;
3
4			//---IMPORTS---
5			import java.util.Properties;
6	ajm	1.2	import java.io.*;
7	ajm	1.1
8			/**
9			* Provides configuration details to Conient
10			* This class is a Singleton class and
11			*
12	ajm	1.2	* @author $Author: ajm4 $
13			* @version $Id: Configuration.java,v 1.1 2001/01/30 02:13:34 ajm4 Exp $
14	ajm	1.1	*/
15			public class Configuration {
16
17			//---FINAL ATTRIBUTES---
18
19			/**
20			* The current CVS revision of this class
21			*/
22	ajm	1.2	public static final String REVISION = "$Revision: 1.1 $";
23	ajm	1.1
24			//---STATIC METHODS---
25
26			/**
27			* Creates and initialises a the Configuration
28			* system for Conient. This calls the private
29			* constructor and ensures this class is a singleton.
30			*
31			* @param configFile the path to the file that this configuration should load
32			*/
33			public static void initialise(String configFile) {
34			_instance = new Configuration(configFile);
35			}
36
37			/**
38			* Returns the singleton instance of this
39			* class.
40			* This will throw a runtime exception if it
41			* is called at the wrong time!
42			*
43			* @return the singleton instance
44			*/
45			public static Configuration getInstance() {
46			if (_instance == null) {
47			throw new RuntimeException("Configuration class requested but HASN'T been initialised!");
48			}
49			return _instance;
50			}
51
52			//---CONSTRUCTORS---
53
54			/**
55			* The private constructor, ensures that this is a singleton.
56			* Simply reads in the local configuration from the file.
57			* Then sets the current properties to be this configuration.
58			* Later the system will obtain further configuration from the
59			* server.
60			*
61			* @param configFile the path to the file that this configuration should load
62			*/
63			private Configuration(String configFile) {
64			try {
65			_properties = readFileConfiguration(configFile);
66			} catch (FileNotFoundException e) {
67			// should show a box!
68			System.err.println("ERROR{configuration}: file not found - " + e.getMessage());
69			} catch (IOException e) {
70			// should show a box!
71			System.err.println("ERROR{configuration}: i/o error - " + e.getMessage());
72			}
73			}
74
75			//---PUBLIC METHODS---
76
77	ajm	1.2	public void readServerConfiguration(BufferedReader in, PrintWriter out) throws IOException {
78			String response = null;
79			out.println("Host.UDPUpdateTime");
80			out.flush();
81			response = in.readLine();
82
83			if (!response.equals("ERROR")) {
84			_properties.setProperty("Host.UDPUpdateTime", response);
85			}
86			out.println("Host.TCPUpdateTime");
87			out.flush();
88			response = in.readLine();
89
90			if (!response.equals("ERROR")) {
91			_properties.setProperty("Host.TCPUpdateTime", response);
92			}
93			}
94
95	ajm	1.1	//---PRIVATE METHODS---
96
97			/**
98			* Reads in the specified file and parses
99			* its properties.
100			*
101			* @param configFile the path of the file to be read
102			* @return the parsed properties
103			*/
104			private Properties readFileConfiguration(String configFile) throws FileNotFoundException, IOException {
105			File file = new File(configFile);
106			Properties configHolder = new Properties();
107			configHolder.load(new FileInputStream(file));
108			return configHolder;
109			}
110
111			//---ACCESSOR/MUTATOR METHODS---
112
113			/**
114			* A wrapper for java.util.Properties.getProperty
115			* When given a key it returns the value of that key
116			* ie, key = value
117			*
118			* @param key the key the value of which is wanted
119			*/
120			public String getProperty(String key) {
121			return _properties.getProperty(key);
122			}
123
124			//---ATTRIBUTES---
125
126			/**
127			* The current configuration in use
128			*/
129			private Properties _properties = null;
130
131			//---STATIC ATTRIBUTES---
132
133			/**
134			* The reference to the singleton instance of this class
135			*/
136			private static Configuration _instance = null;
137			}