jdk-sandbox: comparison src/java.base/share/classes/java/util/Random.java

equal deleted inserted replaced

-:b0c958c0e6c6
+:f02ffcb61dce
 /*
-* Copyright (c) 1995, 2013, 2019, Oracle and/or its affiliates. All rights reserved.
+* Copyright (c) 1995, 2019, Oracle and/or its affiliates. All rights reserved.
-* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
+* 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.  Oracle designates this
+* particular file as subject to the "Classpath" exception as provided
+* by Oracle in the LICENSE file that accompanied this code.
 *
+* 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.
-*
-*
-*
-*
-*
-*
-*
-*
-*
-*
-*
-*
-*
 */
 package java.util;
+import jdk.internal.misc.Unsafe;
 import java.io.*;
 import java.math.BigInteger;
+import java.util.Objects;
+import java.util.ServiceLoader;
+import java.util.ServiceLoader.Provider;
 import java.util.concurrent.atomic.AtomicLong;
-import java.util.function.DoubleConsumer;
+import java.util.function.Function;
-import java.util.function.IntConsumer;
+import java.util.random.AbstractSharedRNG;
-import java.util.function.LongConsumer;
+import java.util.random.RandomNumberGenerator;
-import java.util.stream.DoubleStream;
+import java.util.stream.Collectors;
-import java.util.stream.IntStream;
-import java.util.stream.LongStream;
-import java.util.stream.StreamSupport;
-import jdk.internal.misc.Unsafe;
 /**
 * An instance of this class is used to generate a stream of
 * pseudorandom numbers. The class uses a 48-bit seed, which is
 * modified using a linear congruential formula. (See Donald Knuth,
 *
 * @author  Frank Yellin
 * @since   1.0
 */
 public
-class Random extends AbstractSharedRng implements java.io.Serializable {
+class Random extends AbstractSharedRNG implements java.io.Serializable {
 /** use serialVersionUID from JDK 1.1 for interoperability */
 static final long serialVersionUID = 3905348978240129619L;
 /**
 * The internal state associated with this pseudorandom number generator.
 nextseed = (oldseed * multiplier + addend) & mask;
 } while (!seed.compareAndSet(oldseed, nextseed));
 return (int)(nextseed >>> (48 - bits));
 }
-static final BigInteger thePeriod = BigInteger.valueOf(1L<<48);  // Period is 2**48
+/*
+* Period of Random is 2**48
+*/
+private static final BigInteger PERIOD = BigInteger.valueOf(1L<<48);
 /**
 * Returns the period of this random number generator.
 *
 * @return the period of this random number generator.
 */
 public BigInteger period() {
-	// Here we also take care of checking for instances of class SecureRandom,
+return PERIOD;
-	// just so as not to bother the implementors of that class.
-	// (Any specific instance of SecureRandom can of course override this method.)
-	// The cast to (Object) is of course needed only during development.
-	return ((Object)this instanceof java.security.SecureRandom) ? Rng.HUGE_PERIOD : thePeriod;
 }
 /**
 * Generates random bytes and places them into a user-supplied
 * byte array.  The number of random bytes produced is equal to
 return v1 * multiplier;
 }
 }
 /**
+* Creates a new random number generator that uses the random number generator algorithm
+* specified by name. The seed of the random number generator to a value very likely to be
+* distinct from any other invocation.
+*
+* @param name  name of random number generator algorithm to use.
+*
+* @return an instance of random number generator.
+*
+* @throws IllegalArgumentException if {@code name} is an unknown random number generator
+*
+* @since 14
+*/
+public static RandomNumberGenerator byName(String name) throws IllegalArgumentException {
+Objects.requireNonNull(name);
+Map<String, Provider<RandomNumberGenerator>> rngs = getRNGMap();
+Provider<RandomNumberGenerator> provider = rngs.get(name.toUpperCase());
+if (provider == null) {
+throw new IllegalArgumentException(name + " is an unknown random number generator");
+}
+return provider.get();
+}
+private static Map<String, Provider<RandomNumberGenerator>> rngMap;
+private static Map<String, Provider<RandomNumberGenerator>> getRNGMap() {
+if (rngMap == null) {
+synchronized (Random.class) {
+if (rngMap == null) {
+rngMap = ServiceLoader
+.load(RandomNumberGenerator.class)
+.stream()
+.filter(p -> !p.type().isInterface())
+.collect(Collectors.toMap(p -> p.type().getSimpleName().toUpperCase(),
+Function.identity()));
+}
+}
+}
+return rngMap;
+}
+/**
 * Serializable fields for Random.
 *
 * @serialField    seed long
 *              seed for random computations
 * @serialField    nextNextGaussian double

branch	JDK-8193209-branch
changeset 57437	f02ffcb61dce
parent 57388	b1e6bc96af3d
child 57547	56cbdc3ea079