1.1 --- a/samples/visitor/abstractclass/src-api1.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:35 2008 +0200
     1.2 +++ b/samples/visitor/abstractclass/src-api1.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:36 2008 +0200
     1.3 @@ -27,13 +27,8 @@
     1.4          public void visit(Visitor v) { v.visitNumber(this); }
     1.5      }
     1.6  
     1.7 -    // BEGIN: visitor.visitunknown.v1
     1.8 -    public static abstract class Visitor/*1.0*/ {
     1.9 -        public void visitUnknown(Expression exp) {
    1.10 -            throw new IllegalStateException("Unknown element faced: " + exp);
    1.11 -        }
    1.12 +    public static abstract class Visitor {
    1.13          public abstract void visitPlus(Plus s);
    1.14          public abstract void visitNumber(Number n);
    1.15      }
    1.16 -    // END: visitor.visitunknown.v1
    1.17  }

     2.1 --- a/samples/visitor/abstractclass/src-api2.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:35 2008 +0200
     2.2 +++ b/samples/visitor/abstractclass/src-api2.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:36 2008 +0200
     2.3 @@ -26,6 +26,7 @@
     2.4          @Override
     2.5          public void visit(Visitor v) { v.visitNumber(this); }
     2.6      }
     2.7 +    // BEGIN: visitor.abstractclass.v2
     2.8      /** @since 2.0 */
     2.9      public static final class Minus extends Expression {
    2.10          private final Expression first;
    2.11 @@ -42,17 +43,16 @@
    2.12          }
    2.13      }
    2.14  
    2.15 -    // BEGIN: visitor.visitunknown.v2
    2.16 -    public static abstract class Visitor/*2.0*/ {
    2.17 -        public void visitUnknown(Expression exp) {
    2.18 -            throw new IllegalStateException("Unknown element faced: " + exp);
    2.19 -        }
    2.20 +    public static abstract class Visitor {
    2.21          public abstract void visitPlus(Plus s);
    2.22          public abstract void visitNumber(Number n);
    2.23          /** @since 2.0 */
    2.24          public void visitMinus(Minus s) {
    2.25 -            visitUnknown(s);
    2.26 +            throw new IllegalStateException(
    2.27 +                "Old visitor used on new exceptions"
    2.28 +            );
    2.29          }
    2.30      }
    2.31 -    // END: visitor.visitunknown.v2
    2.32 +    // END: visitor.abstractclass.v2
    2.33 +
    2.34  }

     3.1 --- a/samples/visitor/visitunknown/src-api1.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:35 2008 +0200
     3.2 +++ b/samples/visitor/visitunknown/src-api1.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:36 2008 +0200
     3.3 @@ -27,8 +27,13 @@
     3.4          public void visit(Visitor v) { v.visitNumber(this); }
     3.5      }
     3.6  
     3.7 -    public static abstract class Visitor {
     3.8 +    // BEGIN: visitor.visitunknown.v1
     3.9 +    public static abstract class Visitor/*1.0*/ {
    3.10 +        public void visitUnknown(Expression exp) {
    3.11 +            throw new IllegalStateException("Unknown element faced: " + exp);
    3.12 +        }
    3.13          public abstract void visitPlus(Plus s);
    3.14          public abstract void visitNumber(Number n);
    3.15      }
    3.16 +    // END: visitor.visitunknown.v1
    3.17  }

     4.1 --- a/samples/visitor/visitunknown/src-api2.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:35 2008 +0200
     4.2 +++ b/samples/visitor/visitunknown/src-api2.0/org/apidesign/visitor/Language.java	Sat Jun 14 09:58:36 2008 +0200
     4.3 @@ -26,7 +26,6 @@
     4.4          @Override
     4.5          public void visit(Visitor v) { v.visitNumber(this); }
     4.6      }
     4.7 -    // BEGIN: visitor.abstractclass.v2
     4.8      /** @since 2.0 */
     4.9      public static final class Minus extends Expression {
    4.10          private final Expression first;
    4.11 @@ -42,15 +41,17 @@
    4.12              v.visitMinus(this);
    4.13          }
    4.14      }
    4.15 -
    4.16 -    public static abstract class Visitor {
    4.17 +    // BEGIN: visitor.visitunknown.v2
    4.18 +    public static abstract class Visitor/*2.0*/ {
    4.19 +        public void visitUnknown(Expression exp) {
    4.20 +            throw new IllegalStateException("Unknown element faced: " + exp);
    4.21 +        }
    4.22          public abstract void visitPlus(Plus s);
    4.23          public abstract void visitNumber(Number n);
    4.24 +        /** @since 2.0 */
    4.25          public void visitMinus(Minus s) {
    4.26 -            throw new IllegalStateException(
    4.27 -                "Old visitor used on new exceptions"
    4.28 -            );
    4.29 +            visitUnknown(s);
    4.30          }
    4.31      }
    4.32 -    // END: visitor.abstractclass.v2
    4.33 +    // END: visitor.visitunknown.v2
    4.34  }

     5.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     5.2 +++ b/samples/visitor/visitunknown/src-test/org/apidesign/test/visitor/CountNumbersTest.java	Sat Jun 14 09:58:36 2008 +0200
     5.3 @@ -0,0 +1,51 @@
     5.4 +package org.apidesign.test.visitor;
     5.5 +
     5.6 +import static junit.framework.Assert.*;
     5.7 +import org.apidesign.visitor.Language.Expression;
     5.8 +import org.apidesign.visitor.Language.Number;
     5.9 +import org.apidesign.visitor.Language.Plus;
    5.10 +import org.apidesign.visitor.Language.Visitor;
    5.11 +import org.junit.Test;
    5.12 +
    5.13 +public class CountNumbersTest {
    5.14 +
    5.15 +    // BEGIN: visitor.count.numbers.visitunknown
    5.16 +    private static class CountNumbers extends Visitor/*version1.0*/ {
    5.17 +        int cnt;
    5.18 +
    5.19 +        @Override
    5.20 +        public void visitUnknown(Expression exp) {
    5.21 +            // not a number
    5.22 +        }
    5.23 +        public void visitPlus(Plus s) {
    5.24 +            s.getFirst().visit(this);
    5.25 +            s.getSecond().visit(this);
    5.26 +        }
    5.27 +        public void visitNumber(Number n) {
    5.28 +            cnt++;
    5.29 +        }
    5.30 +    }
    5.31 +
    5.32 +    public static int countNumbers(Expression expression) {
    5.33 +        CountNumbers counter = new CountNumbers();
    5.34 +        expression.visit(counter);
    5.35 +        return counter.cnt;
    5.36 +    }
    5.37 +    // END: visitor.count.numbers.visitunknown
    5.38 +    
    5.39 +    @Test public void printOnePlusOne() {
    5.40 +        Number one = new Number(1);
    5.41 +        Expression expression = new Plus(one, one);
    5.42 +
    5.43 +        assertEquals("Two 1's", 2, countNumbers(expression));
    5.44 +    }
    5.45 +
    5.46 +    @Test public void printOnePlusTwoPlusThree() {
    5.47 +        Number one = new Number(1);
    5.48 +        Number two = new Number(2);
    5.49 +        Number three = new Number(3);
    5.50 +        Expression plus = new Plus(one, new Plus(two, three));
    5.51 +        
    5.52 +        assertEquals("Three", 3, countNumbers(plus));
    5.53 +    }
    5.54 +}

     6.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     6.2 +++ b/samples/visitor/visitunknown/src-test2.0/org/apidesign/test/visitor/InvalidCountNumbersTest.java	Sat Jun 14 09:58:36 2008 +0200
     6.3 @@ -0,0 +1,25 @@
     6.4 +package org.apidesign.test.visitor;
     6.5 +
     6.6 +import static junit.framework.Assert.*;
     6.7 +import org.apidesign.visitor.Language.Expression;
     6.8 +import org.apidesign.visitor.Language.Minus;
     6.9 +import org.apidesign.visitor.Language.Number;
    6.10 +import org.apidesign.visitor.Language.Plus;
    6.11 +import org.junit.Test;
    6.12 +
    6.13 +public class InvalidCountNumbersTest {
    6.14 +    @Test public void printOneMinusTwo() {
    6.15 +        // BEGIN: visitor.visitunknown.traversal
    6.16 +        Number one = new Number(1);
    6.17 +        Number three = new Number(3);
    6.18 +        Number four = new Number(4);
    6.19 +        Expression minus = new Plus(one, new Minus(three, four));
    6.20 +        
    6.21 +        assertEquals(
    6.22 +            "Should have three numbers, but visitor does not " +
    6.23 +            "know how to go through minus", 
    6.24 +            3, CountNumbersTest.countNumbers(minus)
    6.25 +        );
    6.26 +        // END: visitor.visitunknown.traversal
    6.27 +    }
    6.28 +}