Brian Jones <[EMAIL PROTECTED]> writes:
"Jochen Hoenicke" <[EMAIL PROTECTED]> writes:
> Hello,
>
> The clone method in java.util.Vector and some other collection
> classes is incompatible with the behaviour of the Sun Java methods:
>
> When I extend java.util.Vector and clone that class, the result is a
> java.util.Vector and not the extended class. This is also true, when
> I clone java.util.Stack.
Jochen,
If you'd like to submit a diff, I'll add it to the CVS tree. The same
for anybody who wants to point out a problem, but thanks very much for
the heads up on this.
Brian
Okay here is a patch for Vector, Hashtable, HashMap and HashSet. I
don't have a working japhar, yet, so I can't test if it even
compiles. But the patch is quite trivial and should be correct.
diff -u classpath/java/util/HashMap.java classpath/java/util/new/HashMap.java
--- classpath/java/util/HashMap.java Fri Nov 13 16:39:19 1998
+++ classpath/java/util/new/HashMap.java Sat Nov 14 13:08:42 1998
@@ -212,15 +212,14 @@
*/
public Object clone()
{
- Map.Entry entry;
- Iterator it = entrySet().iterator();
- HashMap clone = new HashMap(capacity, loadFactor);
- while (it.hasNext())
- {
- entry = (Map.Entry) it.next();
- clone.internalPut(entry.getKey(), entry.getValue());
- }
- return clone;
+ try {
+ HashMap clone = (HashMap) super.clone();
+ clone.clear();
+ clone.putAll(this);
+ return clone;
+ } catch (CloneNotSupportedException ex) {
+ return null;
+ }
}
/** returns a "set view" of this HashMap's keys */
diff -u classpath/java/util/HashSet.java classpath/java/util/new/HashSet.java
--- classpath/java/util/HashSet.java Fri Nov 13 16:39:19 1998
+++ classpath/java/util/new/HashSet.java Sat Nov 14 13:07:25 1998
@@ -133,11 +133,13 @@
*/
public Object clone()
{
- Iterator it = iterator();
- HashSet clone = new HashSet(map.capacity, map.loadFactor);
- while (it.hasNext())
- clone.internalAdd(it.next());
- return clone;
+ try {
+ HashSet clone = (HashSet) super.clone();
+ clone.map = (HashMap) map.clone();
+ return clone;
+ } catch (CloneNotSupportedException ex) {
+ return null;
+ }
}
/**
diff -u classpath/java/util/Hashtable.java classpath/java/util/new/Hashtable.java
--- classpath/java/util/Hashtable.java Fri Nov 13 16:39:43 1998
+++ classpath/java/util/new/Hashtable.java Sat Nov 14 13:06:35 1998
@@ -474,15 +474,14 @@
*/
public synchronized Object clone()
{
- Map.Entry entry;
- Iterator it = entrySet().iterator();
- Hashtable clone = new Hashtable(capacity, loadFactor);
- while (it.hasNext())
- {
- entry = (Map.Entry) it.next();
- clone.internalPut(entry.getKey(), entry.getValue());
- }
- return clone;
+ try {
+ Hashtable clone = (Hashtable) super.clone();
+ clone.clear();
+ clone.putAll(this);
+ return clone;
+ } catch (CloneNotSupportedException ex) {
+ return null;
+ }
}
/**
diff -u classpath/java/util/Vector.java classpath/java/util/new/Vector.java
--- classpath/java/util/Vector.java Fri Nov 13 16:40:34 1998
+++ classpath/java/util/new/Vector.java Sat Nov 14 12:59:45 1998
@@ -453,7 +453,14 @@
* Creates a new Vector with the same contents as this one.
*/
public Object clone() {
- return new Vector(this);
+ try {
+ Vector clone = (Vector) super.clone();
+ clone.elementData = new Object[elementCount];
+ System.arraycopy(elementData, 0, clone.elementData, 0, elementCount);
+ return clone;
+ } catch (CloneNotSupportedException ex) {
+ return null;
+ }
}
/**
