Mega Code Archive
The clone operation works for only a few items in the standard Java library
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// : appendixa:Cloning.java
// The clone() operation works for only a few
// items in the standard Java library.
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
import java.util.ArrayList;
import java.util.Iterator;
class Int {
private int i;
public Int(int ii) {
i = ii;
}
public void increment() {
i++;
}
public String toString() {
return Integer.toString(i);
}
}
public class Cloning {
public static void main(String[] args) {
ArrayList v = new ArrayList();
for (int i = 0; i < 10; i++)
v.add(new Int(i));
System.out.println("v: " + v);
ArrayList v2 = (ArrayList) v.clone();
// Increment all v2's elements:
for (Iterator e = v2.iterator(); e.hasNext();)
((Int) e.next()).increment();
// See if it changed v's elements:
System.out.println("v: " + v);
}
} ///:~
]]>