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diff --git a/qtjava/javalib/test/ISBNValidator.java b/qtjava/javalib/test/ISBNValidator.java
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+++ b/qtjava/javalib/test/ISBNValidator.java
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+/** From 'Programming in Qt', page 180  */
+
+import org.kde.qt.*;
+
+/**
+  * A class that validates ISBN numbers. See the text for the
+  * specification.
+  */
+public class ISBNValidator extends QValidator
+{
+	public ISBNValidator()
+	{
+		super(null,null);
+	}
+	
+	/**
+	  * This method is called after every input. Since we can check every
+	  * character as soon as it is entered, we only need to check one
+	  * character at a time for validity. To determine whether
+	  * the whole string is acceptable, we must look at the whole
+	  * string
+	  * Note that input can also be deleted. This makes it useless
+	  * to save state (like the number of entered digits) between
+	  * invocations of validate(), because we would have to keep an extra
+	  * copy of the last string.
+	  */
+	public int validate(StringBuffer text, int[] position)
+	{
+		int pos = position[0] - 1;
+		
+		if( text.length() == 0 )
+			return Valid;
+			
+		/* Protect against spurious calls to validate() */
+		if (pos > text.length() )
+			return Valid;
+			
+		/* Anything but decimal digits and dashes is invalid. We only need
+		 * to check the character at the cursor positions. This speeds
+		 * things up massively.
+		 */
+		if( !Character.isDigit(text.charAt(pos)) && ( text.charAt(pos) != '-' ) )
+		{
+			System.out.println( "Typed character is neither digit nor dash" );
+			return Invalid;
+		}
+		
+		/* Dashes are only valid at position 1 (the second position),
+		 * position 8 (if there was no dash at position 1), or position 9 (if
+		 * there was a dash at position 1).
+		 */
+		if( text.charAt(pos) == '-' )
+		{
+			if( pos != 1 && pos != 8 && pos != 9 )
+			{
+				System.out.println( "Dash at wrong position" );
+				return Invalid;
+			}
+			
+			if( ( pos == 8 && text.charAt(1) == '-' ) ||
+			    ( pos == 9 && text.charAt(1) != '-' ) )
+			{
+				System.out.println( "Dash at wrong position" );
+				return Invalid;
+			}
+		}
+		
+		/* If the characters entered so far are valid, but the string
+		 * contains less than ten digits, it could be made acceptable, but
+		 * is not yet.
+		 */
+		int numdigits = text.length();
+		if( text.length() > 1 && text.charAt(1) == '-' ) numdigits--;
+		if( text.length() > 8 && text.charAt(8) == '-' ) numdigits--;
+		if( text.length() > 9 && text.charAt(9) == '-' ) numdigits--;
+		
+		if( numdigits < 10 )
+		{
+			System.out.println( "Less than ten digits; input valid but not yet acceptable" );
+			return Valid;
+		}
+		
+		if( numdigits > 10 )
+		{
+			System.out.println( "More than ten digits; input invalid" );
+			return Invalid;
+		}
+		
+		if( text.charAt(1) != '-' || text.charAt(9) != '-' )
+		{
+			System.out.println( "Ten digits, but dashes not in the right places. Could be fixed up" );
+			return Valid;
+		}
+		
+		System.out.println( "Input acceptable" );
+		return Acceptable;
+	}	
+	
+	/**
+	  * This method is called when the user has pressed return, but
+	  * validate() has judged the string valid but not acceptable. Note
+	  * that fixup() is not required to return an acceptable string. It is
+	  * guaranteed that the caller will validate() the string once again
+	  * after the call to fixup().
+	  */
+	public void fixup(StringBuffer text)
+	{
+		/* We can fix the input only if the dashes are missing,
+		 * since we cannot implement the missing digits. (We could at least
+		 * compute the last one with the checksum algorithm, but won't do so
+		 * here.)
+		 */
+		
+		/* If at least one digit has been entered but there is no dash at
+		 * position 1, insert one.
+		 */
+		if( text.length() > 1 && text.charAt(1) != '-' )
+			text.insert( 1, "-" );
+			
+		/* If at least nine digits have been entered but there is no dash
+		 * at position 10 (because of the last two lines, we can safely
+		 * assume that the first dash is already in place), insert one.
+		 */
+		if( text.length() > 10 /* nine digits plus dash */ && text.charAt(10) != '-' )
+			text.insert( 10, "-" );
+			
+	}
+	
+	
+	public static void main(String[] args)
+	{
+		class ReturnReceiver extends QObject {
+			public void slotReturnPressed()
+			{
+				System.out.println( "return pressed - input accepted" );
+			}
+		}
+		
+		QApplication myapp = new QApplication( args );
+		
+		// create a line edit
+		QLineEdit myedit = new QLineEdit((QWidget) null);
+		myedit.resize( 100, 30 );
+		
+		// create and assign a validator for the line edit
+		ISBNValidator myvalidator = new ISBNValidator();
+		myedit.setValidator(myvalidator);
+		
+		// set up a receiver for the returnPressed() signal
+		ReturnReceiver receiver = new ReturnReceiver();
+		QObject.connect( myedit, SIGNAL( "returnPressed()" ),
+						 receiver, SLOT( "slotReturnPressed()" ) );
+						
+		myapp.setMainWidget( myedit );
+		myedit.show();
+		myapp.exec();
+		return;
+	}
+	
+	static {
+                qtjava.initialize();
+	}
+}