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// virtual_poly test
import virtual_poly.*;
public class virtual_poly_runme {
static {
try {
System.loadLibrary("virtual_poly");
} catch (UnsatisfiedLinkError e) {
System.err.println("Native code library failed to load. See the chapter on Dynamic Linking Problems in the SWIG Java documentation for help.\n" + e);
System.exit(1);
}
}
public static void main(String argv[]) {
NDouble d = new NDouble(3.5);
NInt i = new NInt(2);
//
// These two natural 'copy' forms fail because no covariant (polymorphic) return types
// are supported in Java.
//
// NDouble dc = d.copy();
// NInt ic = i.copy();
//
// Unlike C++, we have to downcast instead.
//
NDouble dc = (NDouble)d.copy();
NInt ic = (NInt)i.copy();
NDouble ddc = NDouble.narrow(dc);
NInt dic = NInt.narrow(ic);
virtual_poly.incr(ic);
if ( (i.get() + 1) != ic.get() )
throw new RuntimeException("incr test failed");
//
// Checking a pure user downcast
//
NNumber n1 = d.copy();
NNumber n2 = d.nnumber();
NDouble dn1 = NDouble.narrow(n1);
NDouble dn2 = NDouble.narrow(n2);
if ( (dn1.get()) != dn2.get() )
throw new RuntimeException("copy/narrow test failed");
//
// Checking the ref polymorphic case
//
NNumber nr = d.ref_this();
NDouble dr1 = NDouble.narrow(nr);
NDouble dr2 = (NDouble)d.ref_this();
if ( dr1.get() != dr2.get() )
throw new RuntimeException("copy/narrow test failed");
}
}
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