1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/samples/cloneproblem/test/org/apidesign/cloneproblem/ExploitTest.java	Thu Oct 30 21:30:10 2014 +0100
     1.3 @@ -0,0 +1,44 @@
     1.4 +package org.apidesign.cloneproblem;
     1.5 +
     1.6 +import java.util.Date;
     1.7 +import junit.framework.TestCase;
     1.8 +
     1.9 +/** Test that would be written by the API hacker.
    1.10 + *
    1.11 + * @author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
    1.12 + */
    1.13 +public class ExploitTest extends TestCase {
    1.14 +    public ExploitTest(String name) {
    1.15 +        super(name);
    1.16 +    }
    1.17 +
    1.18 +    public void testExploitOverridableClone() {
    1.19 +        try {
    1.20 +            HackedDate now = new HackedDate();
    1.21 +            HackedDate later = new HackedDate(now.getTime() + 1000);
    1.22 +            
    1.23 +            Interval interval = new Interval(now, later);
    1.24 +            assertEquals("1s", 1000, interval.getLength());
    1.25 +            
    1.26 +            fail("And I hoped NullPointerException will be thrown!");
    1.27 +        }  catch (NullPointerException ex) {
    1.28 +            // success, the quest is to generate NullPointerException!
    1.29 +        }
    1.30 +    }
    1.31 +
    1.32 +    // BEGIN: interval.exploit
    1.33 +    private static class HackedDate extends Date {
    1.34 +        public HackedDate() {
    1.35 +        }
    1.36 +
    1.37 +        public HackedDate(long date) {
    1.38 +            super(date);
    1.39 +        }
    1.40 +
    1.41 +        @Override
    1.42 +        public Object clone() {
    1.43 +            return null;
    1.44 +        }
    1.45 +    }
    1.46 +    // END: interval.exploit
    1.47 +}