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/*
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 *
 * Copyright (c) 2011-2012 Oracle and/or its affiliates. All rights reserved.
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// Portions Copyright [2018] [Payara Foundation and/or its affiliates]
package org.glassfish.security.common;

import java.security.SecureRandom;

/**
 * An utility class that supplies an Initialized SecureRandom.
 */
public class SharedSecureRandomImpl {

    // the generator has a large period (in Sun's standard implementation, based on the 160-bit SHA1 hash function, the
    // period is 2^160);
    private static final SecureRandom secureRandom = new SecureRandom();

    static {
        // always call java.security.SecureRandom.nextBytes(byte[])
        // immediately after creating a new instance of the PRNG.
        // This will force the PRNG to seed itself securely
        byte[] key = new byte[20];
        secureRandom.nextBytes(key);
    }

    /**
     * Can a single java.security.SecureRandom instance be shared safely by multiple threads ?. Yes. As far as I know.
     * nextBytes and setSeed are sync'd.
     */
    public static SecureRandom get() {
        return secureRandom;
    }

}