/*
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Aug 28, 2009
*/
package com.bigdata.btree.raba.codec;
import java.util.Arrays;
import java.util.Random;
import com.bigdata.btree.keys.TestKeyBuilder;
import com.bigdata.util.BytesUtil.UnsignedByteArrayComparator;
/**
* Generate <i>n</i> random and distinct URIs. This distribution has a shared
* prefix followed by some random bytes representing an integer value. There are
* no <code>null</code>s, even for the B+Tree values.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public class RandomURIGenerator implements IRabaGenerator {
/** Yes. */
public boolean isKeysGenerator() {
return true;
}
/** Yes. */
public boolean isValuesGenerator() {
return true;
}
private final Random r;
public RandomURIGenerator(final Random r) {
this.r = r;
}
public byte[][] generateKeys(int size) {
final byte[][] data = getRandomURIs(size, r);
// put into sorted order.
Arrays.sort(data, 0, data.length, UnsignedByteArrayComparator.INSTANCE);
return data;
}
public byte[][] generateValues(int size) {
final byte[][] data = getRandomURIs(size, r);
return data;
}
/**
* Generate <i>n</i> random and distinct URIs. This distribution has a
* shared prefix followed by some random bytes representing an integer
* value.
*
* @return Distinct but <em>unordered</em> URIs coded as unsigned byte[]s.
*/
byte[][] getRandomURIs(final int n, final Random r) {
final byte[][] data = new byte[n][];
final String ns = "http://www.bigdata.com/rdf#";
long lastCounter = r.nextInt();
for (int i = 0; i < data.length; i++) {
data[i] = TestKeyBuilder.asSortKey(ns + String.valueOf(lastCounter));
final int inc = r.nextInt(100) + 1;
assert inc > 0 : "inc=" + inc;
lastCounter += inc;
}
return data;
}
}