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* "This product includes software developed by the
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* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* List to synchronize its behaviour
* for a multi-threaded environment.
*
* Methods are synchronized, then forwarded to the decorated list.
*
* @since Commons Collections 3.0
* @version $Revision: 1.2 $ $Date: 2004/01/14 21:43:17 $
*
* @author Stephen Colebourne
*/
public class SynchronizedList extends SynchronizedCollection implements List {
/**
* Factory method to create a synchronized list.
*
* @param list the list to decorate, must not be null
* @throws IllegalArgumentException if list is null
*/
public static List decorate(List list) {
return new SynchronizedList(list);
}
//-----------------------------------------------------------------------
/**
* Constructor that wraps (not copies).
*
* @param list the list to decorate, must not be null
* @throws IllegalArgumentException if list is null
*/
protected SynchronizedList(List list) {
super(list);
}
/**
* Constructor that wraps (not copies).
*
* @param list the list to decorate, must not be null
* @param lock the lock to use, must not be null
* @throws IllegalArgumentException if list is null
*/
protected SynchronizedList(List list, Object lock) {
super(list, lock);
}
/**
* Gets the decorated list.
*
* @return the decorated list
*/
protected List getList() {
return (List) collection;
}
//-----------------------------------------------------------------------
public void add(int index, Object object) {
synchronized (lock) {
getList().add(index, object);
}
}
public boolean addAll(int index, Collection coll) {
synchronized (lock) {
return getList().addAll(index, coll);
}
}
public Object get(int index) {
synchronized (lock) {
return getList().get(index);
}
}
public int indexOf(Object object) {
synchronized (lock) {
return getList().indexOf(object);
}
}
public int lastIndexOf(Object object) {
synchronized (lock) {
return getList().lastIndexOf(object);
}
}
/**
* Iterators must be manually synchronized.
*
* synchronized (coll) {
* ListIterator it = coll.listIterator();
* // do stuff with iterator
* }
*
* @return an iterator that must be manually synchronized on the collection
*/
public ListIterator listIterator() {
return getList().listIterator();
}
/**
* Iterators must be manually synchronized.
*
* synchronized (coll) {
* ListIterator it = coll.listIterator(3);
* // do stuff with iterator
* }
*
* @return an iterator that must be manually synchronized on the collection
*/
public ListIterator listIterator(int index) {
return getList().listIterator(index);
}
public Object remove(int index) {
synchronized (lock) {
return getList().remove(index);
}
}
public Object set(int index, Object object) {
synchronized (lock) {
return getList().set(index, object);
}
}
public List subList(int fromIndex, int toIndex) {
synchronized (lock) {
List list = getList().subList(fromIndex, toIndex);
// the lock is passed into the constructor here to ensure that the sublist is
// synchronized on the same lock as the parent list
return new SynchronizedList(list, lock);
}
}
}