Returns a random long within the specified range. - Android java.util

Android examples for java.util:Random Integer

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Description

Returns a random long within the specified range.

Demo Code

/*//from  w  w  w  . j  av  a  2 s.  c o  m
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
import java.util.Random;

public class Main{
    /**
     * Random object used by random method. This has to be not local to the
     * random method so as to not return the same value in the same millisecond.
     */
    private static final Random RANDOM = new Random();
    /**
     * <p>
     * Returns a random long within the specified range.
     * </p>
     * 
     * @param startInclusive
     *            the smallest value that can be returned, must be non-negative
     * @param endExclusive
     *            the upper bound (not included)
     * @throws IllegalArgumentException
     *             if {@code startInclusive > endExclusive} or if
     *             {@code startInclusive} is negative
     * @return the random long
     */
    public static long nextLong(final long startInclusive,
            final long endExclusive) {
        Validate.isTrue(endExclusive >= startInclusive,
                "Start value must be smaller or equal to end value.");
        Validate.isTrue(startInclusive >= 0,
                "Both range values must be non-negative.");

        if (startInclusive == endExclusive) {
            return startInclusive;
        }

        return (long) nextDouble(startInclusive, endExclusive);
    }
    /**
     * <p> 
     * Returns a random double within the specified range.
     * </p>
     * 
     * @param startInclusive
     *            the smallest value that can be returned, must be non-negative
     * @param endInclusive
     *            the upper bound (included)
     * @throws IllegalArgumentException
     *             if {@code startInclusive > endInclusive} or if
     *             {@code startInclusive} is negative
     * @return the random double
     */
    public static double nextDouble(final double startInclusive,
            final double endInclusive) {
        Validate.isTrue(endInclusive >= startInclusive,
                "Start value must be smaller or equal to end value.");
        Validate.isTrue(startInclusive >= 0,
                "Both range values must be non-negative.");

        if (startInclusive == endInclusive) {
            return startInclusive;
        }

        return startInclusive
                + ((endInclusive - startInclusive) * RANDOM.nextDouble());
    }
}

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