/*
* file: PointersAndReferences.java
* package: oreilly.hcj.review
*
* This software is granted under the terms of the Common Public License,
* CPL, which may be found at the following URL:
* http://www-124.ibm.com/developerworks/oss/CPLv1.0.htm
*
* Copyright(c) 2003-2005 by the authors indicated in the @author tags.
* All Rights are Reserved by the various authors.
*
########## DO NOT EDIT ABOVE THIS LINE ########## */
import java.util.Vector;
/**
* Demonstration of the Pointers and References Concept.
*
* @author <a href=mailto:kraythe@arcor.de>Robert Simmons jr. (kraythe)</a>
* @version $Revision: 1.3 $
*/
public class PointersAndReferences {
/**
* Main method.
*
* @param args Command Line arguments.
*/
public static final void main(final String[] args) {
Vector source = new Vector();
source.add("O'Reilly");
source.add("XML");
source.add("Java");
System.out.println("Original Vector");
System.out.println(source.toString());
// -- Try the first method.
someMethod(source);
System.out.println("After first method.");
System.out.println(source.toString());
// -- Try the second method.
someOtherMethod(source);
System.out.println("After second method.");
System.out.println(source.toString());
}
/**
* Try using a vector without changing it.
*
* @param source The source Vector.
*/
public static void someMethod(Vector source) {
Vector target = source;
target.add("Swing");
}
/**
* Try using a vector without changing it with final parameter.
*
* @param source The source Vector.
*/
public static void someOtherMethod(final Vector source) {
Vector target = source;
target.add("JFC"); // ouch, still changes v.
// source = new Vector(); // compiler error.
}
}
/* ########## End of File ########## */
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