/*
* Copyright 2009 Google Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import java.util.Random;
import java.math.BigInteger;
public enum ArrayBuilder {
// These seven are from Tim's paper (listsort.txt)
RANDOM_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = rnd.nextInt();
return result;
}
},
DESCENDING_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = len - i;
return result;
}
},
ASCENDING_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = i;
return result;
}
},
ASCENDING_3_RND_EXCH_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = i;
for (int i = 0; i < 3; i++)
swap(result, rnd.nextInt(result.length),
rnd.nextInt(result.length));
return result;
}
},
ASCENDING_10_RND_AT_END_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
int endStart = len - 10;
for (int i = 0; i < endStart; i++)
result[i] = i;
for (int i = endStart; i < len; i++)
result[i] = rnd.nextInt(endStart + 10);
return result;
}
},
ALL_EQUAL_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = 666;
return result;
}
},
DUPS_GALORE_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = rnd.nextInt(4);
return result;
}
},
RANDOM_WITH_DUPS_INT {
public Object[] build(int len) {
Integer[] result = new Integer[len];
for (int i = 0; i < len; i++)
result[i] = rnd.nextInt(len);
return result;
}
},
PSEUDO_ASCENDING_STRING {
public String[] build(int len) {
String[] result = new String[len];
for (int i = 0; i < len; i++)
result[i] = Integer.toString(i);
return result;
}
},
RANDOM_BIGINT {
public BigInteger[] build(int len) {
BigInteger[] result = new BigInteger[len];
for (int i = 0; i < len; i++)
result[i] = HUGE.add(BigInteger.valueOf(rnd.nextInt(len)));
return result;
}
};
public abstract Object[] build(int len);
public void resetRandom() {
rnd = new Random(666);
}
private static Random rnd = new Random(666);
private static void swap(Object[] a, int i, int j) {
Object t = a[i];
a[i] = a[j];
a[j] = t;
}
private static BigInteger HUGE = BigInteger.ONE.shiftLeft(100);
}