/******************************************************************************* | |
* Copyright (c) 1998, 2013 Oracle and/or its affiliates. All rights reserved. | |
* This program and the accompanying materials are made available under the | |
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 | |
* which accompanies this distribution. | |
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html | |
* and the Eclipse Distribution License is available at | |
* http://www.eclipse.org/org/documents/edl-v10.php. | |
* | |
* Contributors: | |
* Oracle - initial API and implementation from Oracle TopLink | |
******************************************************************************/ | |
package org.eclipse.persistence.internal.helper; | |
import java.util.*; | |
import org.eclipse.persistence.exceptions.ValidationException; | |
/** | |
* Special List/Vector subclass that allows concurrent | |
* population of the contents while the list is in use. | |
* The list will allow iteration while it is still being populated | |
* to allow concurrent processing of the contents. | |
* Other API such as size that require to full contents know will wait until | |
* the list is notified as being complete. | |
* This is use to allow the rows and objects of a read-all query to be processed concurrently. | |
* | |
* @author James Sutherland | |
* @since OracleAS 10g TopLink (10.0.3) | |
*/ | |
public class ThreadCursoredList extends Vector { | |
/** Store if the list is fully populated. */ | |
protected boolean isComplete; | |
/** Used to throw exception that occur from the concurrent population thread. */ | |
protected RuntimeException exception; | |
/** | |
* Construct an empty list so that its internal data array | |
* has size <tt>10</tt> and its standard capacity increment is zero. | |
*/ | |
public ThreadCursoredList() { | |
this(10); | |
} | |
/** | |
* Construct an empty list with the specified initial capacity and | |
* with its capacity increment equal to zero. | |
*/ | |
public ThreadCursoredList(int initialCapacity) { | |
this(initialCapacity, 0); | |
} | |
/** | |
* Construct an empty list with the specified initial capacity and | |
* capacity increment. | |
*/ | |
public ThreadCursoredList(int initialCapacity, int capacityIncrement) { | |
super(0); | |
this.isComplete = false; | |
} | |
/** | |
* Add and notify any waiters that there are new elements. | |
*/ | |
public synchronized void add(int index, Object element) { | |
super.add(index, element); | |
this.notifyAll(); | |
} | |
/** | |
* Add and notify any waiters that there are new elements. | |
*/ | |
public synchronized boolean add(Object element) { | |
boolean result = super.add(element); | |
notifyAll(); | |
return result; | |
} | |
/** | |
* Add and notify any waiters that there are new elements. | |
*/ | |
public synchronized boolean addAll(int index, Collection collection) { | |
boolean result = super.addAll(index, collection); | |
notifyAll(); | |
return result; | |
} | |
/** | |
* Add and notify any waiters that there are new elements. | |
*/ | |
public synchronized boolean addAll(Collection collection) { | |
boolean result = super.addAll(collection); | |
notifyAll(); | |
return result; | |
} | |
/** | |
* Add and notify any waiters that there are new elements. | |
*/ | |
public synchronized void addElement(Object object) { | |
super.addElement(object); | |
notifyAll(); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized void clear() { | |
waitUntilComplete(); | |
super.clear(); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized Object clone() { | |
waitUntilComplete(); | |
return super.clone(); | |
} | |
/** | |
* Return if any exception that was throw from concurrent population thread. | |
*/ | |
public boolean hasException() { | |
return exception != null; | |
} | |
/** | |
* Return any exception that was throw from concurrent population thread. | |
*/ | |
public RuntimeException getException() { | |
return exception; | |
} | |
/** | |
* Record that the population thread hit an exception, | |
* that should be thrown to the processing thread on the next access. | |
* This also records the list and complete. | |
*/ | |
public synchronized void throwException(RuntimeException exception) { | |
this.exception = exception; | |
setIsComplete(true); | |
} | |
/** | |
* Return if the list is complete. | |
* If an exception was thrown during the concurrent population throw the exception. | |
*/ | |
public synchronized boolean isComplete() { | |
if (exception != null) { | |
// Set the exception to null so it is only thrown once. | |
RuntimeException thrownException = this.exception; | |
this.exception = null; | |
throw thrownException; | |
} | |
return isComplete; | |
} | |
/** | |
* Set the list complete and notify any waiters. | |
*/ | |
public synchronized void setIsComplete(boolean isComplete) { | |
this.isComplete = isComplete; | |
notifyAll(); | |
} | |
/** | |
* Wait until the list has been fully populated. | |
*/ | |
public synchronized void waitUntilComplete() { | |
while (!isComplete()) { | |
try { | |
wait(); | |
} catch (InterruptedException ignore) { | |
} | |
} | |
} | |
/** | |
* Wait until a new element has been added. | |
*/ | |
public synchronized void waitUntilAdd() { | |
try { | |
wait(); | |
} catch (InterruptedException ignore) { | |
} | |
} | |
/** | |
* If it does not contain the object must wait until it is complete. | |
*/ | |
public synchronized boolean contains(Object element) { | |
boolean result = super.contains(element); | |
if ((result != true) && (!isComplete())) { | |
waitUntilComplete(); | |
result = super.contains(element); | |
} | |
return result; | |
} | |
/** | |
* If it does not contain the object must wait until it is complete. | |
*/ | |
public synchronized boolean containsAll(Collection collection) { | |
boolean result = super.containsAll(collection); | |
if ((result != true) && (!isComplete())) { | |
waitUntilComplete(); | |
result = super.containsAll(collection); | |
} | |
return result; | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized void copyInto(Object[] array) { | |
waitUntilComplete(); | |
super.copyInto(array); | |
} | |
/** | |
* If the index is beyond the size wait until complete. | |
*/ | |
public synchronized Object elementAt(int index) { | |
Object result = super.elementAt(index); | |
if ((result == null) && (!isComplete())) { | |
waitUntilComplete(); | |
result = super.elementAt(index); | |
} | |
return result; | |
} | |
protected int getSize() { | |
return super.size(); | |
} | |
/** | |
* Allow concurrent streaming of the elements. | |
*/ | |
public Enumeration elements() { | |
return new Enumeration() { | |
int count = 0; | |
public boolean hasMoreElements() { | |
synchronized (ThreadCursoredList.this) { | |
boolean result = count < ThreadCursoredList.this.getSize(); | |
while ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = count < ThreadCursoredList.this.getSize(); | |
} | |
return result; | |
} | |
} | |
public Object nextElement() { | |
synchronized (ThreadCursoredList.this) { | |
boolean result = count < ThreadCursoredList.this.getSize(); | |
while ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = count < ThreadCursoredList.this.getSize(); | |
} | |
if (result) { | |
return get(count++); | |
} | |
} | |
throw new NoSuchElementException("Vector Enumeration"); | |
} | |
}; | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized boolean equals(Object object) { | |
waitUntilComplete(); | |
return super.equals(object); | |
} | |
/** | |
* Wait until has an element or is complete. | |
*/ | |
public synchronized Object firstElement() { | |
while ((!isComplete()) && (super.size() < 1)) { | |
waitUntilAdd(); | |
} | |
return super.firstElement(); | |
} | |
/** | |
* Wait until has the element or is complete. | |
*/ | |
public synchronized Object get(int index) { | |
while ((!isComplete()) && (super.size() < index)) { | |
waitUntilAdd(); | |
} | |
return super.get(index); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized int hashCode() { | |
waitUntilComplete(); | |
return super.hashCode(); | |
} | |
/** | |
* If does not contain the object wait until complete. | |
*/ | |
public int indexOf(Object element) { | |
int result = super.indexOf(element); | |
if ((result == -1) && (!isComplete())) { | |
waitUntilComplete(); | |
result = super.indexOf(element); | |
} | |
return result; | |
} | |
/** | |
* If does not contain the object wait until complete. | |
*/ | |
public synchronized int indexOf(Object element, int index) { | |
int result = super.indexOf(element, index); | |
if ((result == -1) && (!isComplete())) { | |
waitUntilComplete(); | |
result = super.indexOf(element, index); | |
} | |
return result; | |
} | |
/** | |
* Add the element a notify any waiters that there are new elements. | |
*/ | |
public synchronized void insertElementAt(Object element, int index) { | |
super.insertElementAt(element, index); | |
notify(); | |
} | |
/** | |
* If empty wait until an element has been added or is complete. | |
*/ | |
public boolean isEmpty() { | |
boolean result = super.isEmpty(); | |
if (result && (!isComplete())) { | |
waitUntilAdd(); | |
result = super.isEmpty(); | |
} | |
return result; | |
} | |
public Iterator iterator() { | |
return listIterator(0); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized Object lastElement() { | |
waitUntilComplete(); | |
return super.lastElement(); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public int lastIndexOf(Object element) { | |
waitUntilComplete(); | |
return super.lastIndexOf(element); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized int lastIndexOf(Object element, int index) { | |
waitUntilComplete(); | |
return super.lastIndexOf(element, index); | |
} | |
public ListIterator listIterator() { | |
return listIterator(0); | |
} | |
/** | |
* Iterate while waiting at end until complete. | |
*/ | |
public ListIterator listIterator(final int index) { | |
return new ListIterator() { | |
int count = index; | |
public boolean hasNext() { | |
synchronized (ThreadCursoredList.this) { | |
boolean result = count < ThreadCursoredList.this.getSize(); | |
while ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = count < ThreadCursoredList.this.getSize(); | |
} | |
return result; | |
} | |
} | |
public Object next() { | |
synchronized (ThreadCursoredList.this) { | |
boolean result = count < ThreadCursoredList.this.getSize(); | |
while ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = count < ThreadCursoredList.this.getSize(); | |
} | |
if (result) { | |
return get(count++); | |
} | |
} | |
throw new NoSuchElementException("Vector Iterator"); | |
} | |
public void remove() { | |
throw ValidationException.operationNotSupported("remove"); | |
} | |
public void set(Object object) { | |
throw ValidationException.operationNotSupported("set"); | |
} | |
public void add(Object object) { | |
throw ValidationException.operationNotSupported("add"); | |
} | |
public int previousIndex() { | |
return count - 1; | |
} | |
public int nextIndex() { | |
return count; | |
} | |
public Object previous() { | |
count--; | |
return get(count); | |
} | |
public boolean hasPrevious() { | |
return count > 0; | |
} | |
}; | |
} | |
/** | |
* If index is missing wait until is there. | |
*/ | |
public synchronized Object remove(int index) { | |
while ((!isComplete()) && (super.size() < index)) { | |
waitUntilAdd(); | |
} | |
return super.remove(index); | |
} | |
/** | |
* If object is missing wait until complete. | |
*/ | |
public boolean remove(Object element) { | |
boolean result = super.remove(element); | |
if ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = super.remove(element); | |
} | |
return result; | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized boolean removeAll(Collection collection) { | |
waitUntilComplete(); | |
return super.removeAll(collection); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized void removeAllElements() { | |
waitUntilComplete(); | |
super.removeAllElements(); | |
} | |
/** | |
* If missing wait until complete. | |
*/ | |
public synchronized boolean removeElement(Object element) { | |
boolean result = super.removeElement(element); | |
if ((!result) && (!isComplete())) { | |
waitUntilAdd(); | |
result = super.removeElement(element); | |
} | |
return result; | |
} | |
/** | |
* If index is missing wait until reasched or complete. | |
*/ | |
public synchronized void removeElementAt(int index) { | |
while ((!isComplete()) && (super.size() < index)) { | |
waitUntilAdd(); | |
} | |
super.removeElementAt(index); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized boolean retainAll(Collection collection) { | |
waitUntilComplete(); | |
return super.retainAll(collection); | |
} | |
/** | |
* If index is missing wait until reached or complete. | |
*/ | |
public synchronized Object set(int index, Object element) { | |
while ((!isComplete()) && (super.size() < index)) { | |
waitUntilAdd(); | |
} | |
return super.set(index, element); | |
} | |
/** | |
* If index is missing wait until reached or complete. | |
*/ | |
public synchronized void setElementAt(Object element, int index) { | |
while ((!isComplete()) && (super.size() < index)) { | |
waitUntilAdd(); | |
} | |
super.setElementAt(element, index); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public int size() { | |
waitUntilComplete(); | |
return super.size(); | |
} | |
/** | |
* If index is missing wait until reached or complete. | |
*/ | |
public List subList(int fromIndex, int toIndex) { | |
while ((!isComplete()) && (super.size() < toIndex)) { | |
waitUntilAdd(); | |
} | |
return super.subList(fromIndex, toIndex); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized Object[] toArray() { | |
waitUntilComplete(); | |
return super.toArray(); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized Object[] toArray(Object[] array) { | |
waitUntilComplete(); | |
return super.toArray(array); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized String toString() { | |
waitUntilComplete(); | |
return super.toString(); | |
} | |
/** | |
* First wait until complete. | |
*/ | |
public synchronized void trimToSize() { | |
waitUntilComplete(); | |
super.trimToSize(); | |
} | |
} |