core/loggers/SimpleSwingLogger.java

//---PACKAGE DECLARATION---
package uk.ac.ukc.iscream.core.loggers;

//---IMPORTS---
import uk.ac.ukc.iscream.util.*;
import uk.ac.ukc.iscream.core.*;
import java.util.Date;
import java.text.DateFormat;
import java.util.Locale;
import javax.swing.*;
import javax.swing.border.*;
import java.awt.Color;

/**
 * The SimpleSwingLogger is an implementation of the LoggerImpl defined
 * in the associated interface. It's only purpose is to simply print
 * all the logging information it receives to a window frame.
 *
 * All very simple really...
 *
 * This class does have the problem that if too many messages are
 * entered into the text area, then it will fill the memory of
 * the JVM.  This MAY have been fixed by adding the setRows(int)
 * in the write(string) method, however the Java API does not
 * specify if this enforces the max rows, but I THINK it does.
 *
 * @author  $Author: ajm4 $
 * @version $Id: SimpleSwingLogger.java,v 1.4 2000/11/29 21:27:25 ajm4 Exp $
 */
public class SimpleSwingLogger extends JFrame implements LoggerImpl {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.4 $";
    
    private final int width = 700;
    private final int height = 400;
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Creates a new Simple Swing Logger.
     */
    public SimpleSwingLogger() {
        _verbosityLevel = Integer.parseInt(System.getProperty("uk.ac.ukc.iscream.Verbosity"));
        _maxMessages = Integer.parseInt(System.getProperty("uk.ac.ukc.iscream.LoggerClass.SimpleSwingLogger.maxMessages"));
        System.out.println(this.toString() + ": opening window");

        // set up the Frame
        setTitle("I-Scream Logger");
        setSize(width, height);
        getContentPane().setBackground(Color.white);
        setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
        Box box = Box.createVerticalBox();

        // create the i-scream logo at the top
        JLabel iscream = new JLabel(new ImageIcon("./uk/ac/ukc/iscream/core/loggers/i-scream.gif"));
        JLabel comment = new JLabel("   I-Scream System Logging Console");
        comment.setForeground( new Color(0, 0, 102));
        iscream.setBackground(Color.white);
        comment.setBackground(Color.white);
        Box header = Box.createHorizontalBox();
        header.add(comment);
        header.add(Box.createHorizontalGlue());
        header.add(iscream);

        // set up the text area
        _textArea.setEditable(false);
        JScrollPane text = new JScrollPane(_textArea);
        text.setBorder(new TitledBorder(new LineBorder(new Color(0, 0, 102)), " Messages "));
        text.setBackground(Color.white);

        // build the frame
        box.add(header);
        box.add(text);
        getContentPane().add(box);

        // show the window
        show();
        write(toString(), Logger.SYSINIT, "started");
        write(toString(), Logger.SYSMSG, "using verbosity " + _verbosityLevel);
    }

//---PUBLIC METHODS---

    /**
     * The write() method takes a message, formats it using the
     * formatLogLine() method, and then outputs it to the screen
     * using the text area. The source is usually the
     * calling object, referenced by `this'. The method has been
     * made synchronized to avoid it being called by two different
     * objects and the output ending up merged on the screen.
     * 
     * @param source A string representation of the calling object.
     * @param verbosity the verbosity of this message
     * @param message The text to be logged.
     */   
    public synchronized void write(String source, int verbosity, String message) {
        if (verbosity <= _verbosityLevel) {
            String line = formatLogLine(source, message);
            _textArea.insert(line + "\n",0);
            _textArea.setRows(_maxMessages);
        }
    }
       
    /**
     * 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.FormatName 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---

    /**
     * This method generates a nicely formatted line for the log,
     * including the date/time and the source of the message. The date
     * and time are formatted using the DateFormat class, and the source
     * class is formatted using the toString() method found in every
     * source file. This is then prepended to the message and returned.
     * 
     * @param source A string representation of the calling object.
     * @param message The message to be logged.
     * @return The string to be written to the log.
     */
    private String formatLogLine(String source, String message){
        String date = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.MEDIUM).format(new Date());
        return "[" + date + "] " + source + ": " + message;
    }

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

//---ATTRIBUTES---

    /**
     * A text area to write log messages to
     */
    private JTextArea _textArea = new JTextArea();


    /**
     * The verbosity level of this instance
     */
    private int _verbosityLevel;
    
    /**
     * The maximum number of messages that can
     * be displayed before bottom items are removed.
     * This is needed to fix the memory overload problem
     * that was seen when the GUI got too full!
     */
    private int _maxMessages;
    
    /**
     * 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 = Core.NAME;
    
//---STATIC ATTRIBUTES---
    
}
Revision:	1.5
Committed:	Tue Dec 12 18:28:54 2000 UTC (23 years, 5 months ago) by ajm
Branch:	MAIN
Changes since 1.4:	+42 -10 lines
Log Message:	brought inline with new standards also hopefully fixed memory leak on the Text area. read class comment for more details
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.ac.ukc.iscream.core.loggers;
3
4	//---IMPORTS---
5	import uk.ac.ukc.iscream.util.*;
6	import uk.ac.ukc.iscream.core.*;
7	import java.util.Date;
8	import java.text.DateFormat;
9	import java.util.Locale;
10	import javax.swing.*;
11	import javax.swing.border.*;
12	import java.awt.Color;
13
14	/**
15	* The SimpleSwingLogger is an implementation of the LoggerImpl defined
16	* in the associated interface. It's only purpose is to simply print
17	* all the logging information it receives to a window frame.
18	*
19	* All very simple really...
20	*
21	* This class does have the problem that if too many messages are
22	* entered into the text area, then it will fill the memory of
23	* the JVM. This MAY have been fixed by adding the setRows(int)
24	* in the write(string) method, however the Java API does not
25	* specify if this enforces the max rows, but I THINK it does.
26	*
27	* @author $Author: ajm4 $
28	* @version $Id: SimpleSwingLogger.java,v 1.4 2000/11/29 21:27:25 ajm4 Exp $
29	*/
30	public class SimpleSwingLogger extends JFrame implements LoggerImpl {
31
32	//---FINAL ATTRIBUTES---
33
34	/**
35	* The current CVS revision of this class
36	*/
37	public final String REVISION = "$Revision: 1.4 $";
38
39	private final int width = 700;
40	private final int height = 400;
41
42	//---STATIC METHODS---
43
44	//---CONSTRUCTORS---
45
46	/**
47	* Creates a new Simple Swing Logger.
48	*/
49	public SimpleSwingLogger() {
50	_verbosityLevel = Integer.parseInt(System.getProperty("uk.ac.ukc.iscream.Verbosity"));
51	_maxMessages = Integer.parseInt(System.getProperty("uk.ac.ukc.iscream.LoggerClass.SimpleSwingLogger.maxMessages"));
52	System.out.println(this.toString() + ": opening window");
53
54	// set up the Frame
55	setTitle("I-Scream Logger");
56	setSize(width, height);
57	getContentPane().setBackground(Color.white);
58	setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
59	Box box = Box.createVerticalBox();
60
61	// create the i-scream logo at the top
62	JLabel iscream = new JLabel(new ImageIcon("./uk/ac/ukc/iscream/core/loggers/i-scream.gif"));
63	JLabel comment = new JLabel(" I-Scream System Logging Console");
64	comment.setForeground( new Color(0, 0, 102));
65	iscream.setBackground(Color.white);
66	comment.setBackground(Color.white);
67	Box header = Box.createHorizontalBox();
68	header.add(comment);
69	header.add(Box.createHorizontalGlue());
70	header.add(iscream);
71
72	// set up the text area
73	_textArea.setEditable(false);
74	JScrollPane text = new JScrollPane(_textArea);
75	text.setBorder(new TitledBorder(new LineBorder(new Color(0, 0, 102)), " Messages "));
76	text.setBackground(Color.white);
77
78	// build the frame
79	box.add(header);
80	box.add(text);
81	getContentPane().add(box);
82
83	// show the window
84	show();
85	write(toString(), Logger.SYSINIT, "started");
86	write(toString(), Logger.SYSMSG, "using verbosity " + _verbosityLevel);
87	}
88
89	//---PUBLIC METHODS---
90
91	/**
92	* The write() method takes a message, formats it using the
93	* formatLogLine() method, and then outputs it to the screen
94	* using the text area. The source is usually the
95	* calling object, referenced by `this'. The method has been
96	* made synchronized to avoid it being called by two different
97	* objects and the output ending up merged on the screen.
98	*
99	* @param source A string representation of the calling object.
100	* @param verbosity the verbosity of this message
101	* @param message The text to be logged.
102	*/
103	public synchronized void write(String source, int verbosity, String message) {
104	if (verbosity <= _verbosityLevel) {
105	String line = formatLogLine(source, message);
106	_textArea.insert(line + "\n",0);
107	_textArea.setRows(_maxMessages);
108	}
109	}
110
111	/**
112	* Overrides the {@link java.lang.Object#toString() Object.toString()}
113	* method to provide clean logging (every class should have this).
114	*
115	* This uses the uk.ac.ukc.iscream.util.FormatName class
116	* to format the toString()
117	*
118	* @return the name of this class and its CVS revision
119	*/
120	public String toString() {
121	return FormatName.getName(
122	_name,
123	getClass().getName(),
124	REVISION);
125	}
126
127	//---PRIVATE METHODS---
128
129	/**
130	* This method generates a nicely formatted line for the log,
131	* including the date/time and the source of the message. The date
132	* and time are formatted using the DateFormat class, and the source
133	* class is formatted using the toString() method found in every
134	* source file. This is then prepended to the message and returned.
135	*
136	* @param source A string representation of the calling object.
137	* @param message The message to be logged.
138	* @return The string to be written to the log.
139	*/
140	private String formatLogLine(String source, String message){
141	String date = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.MEDIUM).format(new Date());
142	return "[" + date + "] " + source + ": " + message;
143	}
144
145	//---ACCESSOR/MUTATOR METHODS---
146
147	//---ATTRIBUTES---
148
149	/**
150	* A text area to write log messages to
151	*/
152	private JTextArea _textArea = new JTextArea();
153
154
155	/**
156	* The verbosity level of this instance
157	*/
158	private int _verbosityLevel;
159
160	/**
161	* The maximum number of messages that can
162	* be displayed before bottom items are removed.
163	* This is needed to fix the memory overload problem
164	* that was seen when the GUI got too full!
165	*/
166	private int _maxMessages;
167
168	/**
169	* This is the friendly identifier of the
170	* component this class is running in.
171	* eg, a Filter may be called "filter1",
172	* If this class does not have an owning
173	* component, a name from the configuration
174	* can be placed here. This name could also
175	* be changed to null for utility classes.
176	*/
177	private String _name = Core.NAME;
178
179	//---STATIC ATTRIBUTES---
180
181	}