Demonstration of overriding fields
/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
*
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*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
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*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/
/** Demonstration of overriding fields. */
public class OverrideField {
public static void main(String[] av) {
System.out.println("OA's version of getAttr returns: " +
new OA().getAttr());
System.out.println("OB's version of getAttr returns: " +
new OB().getAttr());
// Declared as OA, instantiated as OB, so gets OB's version of things.
OA c = new OB();
System.out.println("C's version of getAttr returns: " +
c.getAttr());
}
}
class OA {
final int attr = 1;
int getAttr() {
System.out.println("In OA.getAttr");
return attr;
}
}
class OB extends OA {
final int attr = 2;
int getAttr() {
System.out.println("In OB.getAttr");
super.getAttr(); // Just to show flow of control
return attr;
}
}
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