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Fix test by using downcasts

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git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@5592 626c5289-ae23-0410-ae9c-e8d60b6d4f22
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William S Fulton 2003-12-23 21:51:19 +00:00
commit c81661122e
1 changed files with 10 additions and 17 deletions
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27
Examples/test-suite/java/virtual_poly_runme.java
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@ -18,31 +18,24 @@ public class virtual_poly_runme {
NDouble d = new NDouble(3.5); NDouble d = new NDouble(3.5);
NInt i = new NInt(2); NInt i = new NInt(2);
NInt j = virtual_poly.incr(i);
// //
// These two natural 'copy' forms fail, only java and csharp // These two natural 'copy' forms fail because no covariant (polymorphic) return types
// because no polymorphic return types are supported. // are supported in Java.
// But we can live with this restriction, more or less.
// //
// NDouble dc = d.copy(); // NDouble dc = d.copy();
// NInt ic = i.copy(); // NInt ic = i.copy();
// //
// These two 'copy' forms work, but we end with plain NNumbers // Unlike C++, we have to downcast instead.
// //
NNumber dc = d.copy(); NDouble dc = (NDouble)d.copy();
NNumber ic = i.copy(); NInt ic = (NInt)i.copy();
NDouble ddc = (NDouble)NDouble.narrow(dc);
NInt dic = (NInt)NInt.narrow(ic);
// virtual_poly.incr(ic);
// The real problem is that there is no way to recover the if ( (i.get() + 1) != ic.get() )
// original NInt or NDouble objects, even when you try to use the throw new RuntimeException("incr test failed");
// plain and natural C++ dynamic_cast operation, or the user
// downcasting mechanism:
//
// don't work
NDouble ddc = NDouble.narrow(dc);
NInt dic = NInt.narrow(ic);
} }
} }