/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.datastructures.dbmergesortedds;
import java.util.Comparator;
import java.util.Iterator;
import lupos.datastructures.patriciatrie.TrieSet;
import lupos.datastructures.queryresult.ParallelIterator;
public class DBMergeSortedSetUsingTrie extends DBMergeSortedSet<String> {
protected TrieSet searchtree = TrieSet.createRamBasedTrieSet();
public static long LIMIT_ELEMENTS_IN_SET = 50000000;
public DBMergeSortedSetUsingTrie(final SortConfiguration sortConfiguration, final Class<? extends String> classOfElements){
super(sortConfiguration, classOfElements);
}
public DBMergeSortedSetUsingTrie(){
super();
}
public DBMergeSortedSetUsingTrie(
final Class<? extends String> classOfElements){
super(classOfElements);
}
public DBMergeSortedSetUsingTrie(final SortConfiguration sortConfiguration,
final Comparator<? super String> comp,
final Class<? extends String> classOfElements){
super(sortConfiguration, comp, classOfElements);
}
public DBMergeSortedSetUsingTrie(
final Comparator<? super String> comp,
final Class<? extends String> classOfElements){
super(comp, classOfElements);
}
@Override
public boolean add(final String ele) {
if (searchtree.size()>LIMIT_ELEMENTS_IN_SET) {
writeToRun();
}
if (searchtree.add(ele))
size++;
return true;
}
private void writeToRun() {
if (currentRun == null)
currentRun = Run.createInstance(this);
else
closeAndNewCurrentRun();
for (final String s : searchtree) {
final Entry<String> entry = new Entry<String>(s,
new StandardComparator<String>(), n++);
currentRun.add(entry);
}
searchtree = TrieSet.createRamBasedTrieSet();
}
@Override
public void clear() {
super.clear();
searchtree.clear();
}
public boolean sorted() {
return searchtree.size()==0
&& (currentRun == null || unsortedID == currentRun.runID);
}
@Override
public void sort() {
if (sorted() || currentRun == null)
return;
if (searchtree.size() > 0)
this.writeToRun();
super.sort();
}
@Override
public ParallelIterator<String> iterator() {
// Do we have a small sorted bag? In other words:
// Did we already write entries to disk or is all still stored in main
// memory? In the latter case, we do not need to store it on disk and
// just "sort" in memory!
if (currentRun == null) {
return new ParallelIterator() {
Iterator<String> it = searchtree.iterator();
public void close() {
}
public boolean hasNext() {
return it.hasNext();
}
public Object next() {
return it.next();
}
public void remove() {
}
};
} else
return super.iterator();
}
}