// : appendixa:Snake.java
// Tests cloning to see if destination
// of references are also cloned.
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
public class Snake implements Cloneable {
private Snake next;
private char c;
// Value of i == number of segments
public Snake(int i, char x) {
c = x;
if (--i > 0)
next = new Snake(i, (char) (x + 1));
}
public void increment() {
c++;
if (next != null)
next.increment();
}
public String toString() {
String s = ":" + c;
if (next != null)
s += next.toString();
return s;
}
public Object clone() {
Object o = null;
try {
o = super.clone();
} catch (CloneNotSupportedException e) {
System.err.println("Snake can't clone");
}
return o;
}
public static void main(String[] args) {
Snake s = new Snake(5, 'a');
System.out.println("s = " + s);
Snake s2 = (Snake) s.clone();
System.out.println("s2 = " + s2);
s.increment();
System.out.println("after s.increment, s2 = " + s2);
}
} ///:~