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Design issue: Debugging information"></td></tr><tr><td bgcolor="ffffff" width="15">&nbsp;</td><td bgcolor="ffffff" width="12">&nbsp;</td><td valign="top" align="left" bgcolor="ffffff" width="*"><p><br x="7"><table cellspacing="0" cellpadding="0" border="0"><tr><td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>A little text goes a long way</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr>    page 2 of 2</nobr></font></td></tr></table><br x="7"><br x="7"></p><font size="2" face="Verdana, Arial, Helvetica"><p>

If you supply the source with your library, a user <i>might</i> consider using a debugger, but you shouldn't count on that.

</p><p>

A better way to counter this inevitable problem is to add debugging <code style="font-family: Courier New, Courier, monospace; font-size: 12">println()</code> statements to your code to force each piece of the code to report on what it is doing.  Watching this information can often help the user know where something is going wrong.

</p><p>

The following example demonstrates this technique. The user's code can install a <code style="font-family: Courier New, Courier, monospace; font-size: 12">PrintStream</code> object by calling the static method <code style="font-family: Courier New, Courier, monospace; font-size: 12">Server.setDebugStream()</code>.  Once implemented, the debug information will be sent to the provided stream.

</p><p>

<pre><code style="font-family: Courier New, Courier, monospace; font-size: 12">
  // set this to a print stream if you want debug info
  // sent to it; otherwise, leave it null
  static private PrintStream debugStream;

  // call this to send the debugging output somewhere
  static public void setDebugStream( PrintStream ps ) {
    debugStream = ps;
  }
</code></pre>

</p><p>

You can then sprinkle your library with calls to the <code style="font-family: Courier New, Courier, monospace; font-size: 12">debug()</code> method:

</p><p>

<pre><code style="font-family: Courier New, Courier, monospace; font-size: 12">
  // send debug info to the print stream, if there is one
  static public void debug( String s ) {
    if (debugStream != null)
      debugStream.println( s );
  }
</code></pre>

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