| /** |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.aurora.common.util; |
| |
| import com.google.common.base.Preconditions; |
| |
| /** |
| * An interface to define the common functionality that is required for generating random values. |
| * |
| * @author William Farner |
| */ |
| public interface Random { |
| |
| /** |
| * @see java.util.Random#nextDouble() |
| */ |
| double nextDouble(); |
| |
| /** |
| * @see java.util.Random#nextInt(int) |
| */ |
| int nextInt(int n); |
| |
| /** |
| * A Random that wraps a java.util.Random. |
| */ |
| class SystemRandom implements Random { |
| private final java.util.Random rand; |
| |
| public SystemRandom(java.util.Random rand) { |
| this.rand = Preconditions.checkNotNull(rand); |
| } |
| |
| @Override |
| public double nextDouble() { |
| return rand.nextDouble(); |
| } |
| |
| @Override |
| public int nextInt(int n) { |
| return rand.nextInt(n); |
| } |
| } |
| |
| // Utility class. |
| class Util { |
| private Util() {} |
| |
| /** |
| * Creates a new Random based off the default system Random. |
| * @return A new default Random. |
| */ |
| public static Random newDefaultRandom() { |
| return new SystemRandom(new java.util.Random()); |
| } |
| } |
| } |