1 /* 2 * Copyright 2019 The gRPC Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package io.grpc.xds; 18 19 import java.util.concurrent.ThreadLocalRandom; 20 import javax.annotation.concurrent.ThreadSafe; 21 22 @ThreadSafe // Except for impls/mocks in tests 23 interface ThreadSafeRandom { nextInt(int bound)24 int nextInt(int bound); 25 nextLong()26 long nextLong(); 27 nextLong(long bound)28 long nextLong(long bound); 29 30 final class ThreadSafeRandomImpl implements ThreadSafeRandom { 31 32 static final ThreadSafeRandom instance = new ThreadSafeRandomImpl(); 33 ThreadSafeRandomImpl()34 private ThreadSafeRandomImpl() {} 35 36 @Override nextInt(int bound)37 public int nextInt(int bound) { 38 return ThreadLocalRandom.current().nextInt(bound); 39 } 40 41 @Override nextLong()42 public long nextLong() { 43 return ThreadLocalRandom.current().nextLong(); 44 } 45 46 @Override nextLong(long bound)47 public long nextLong(long bound) { 48 return ThreadLocalRandom.current().nextLong(bound); 49 } 50 } 51 } 52