001/*
002 * nimbus-jose-jwt
003 *
004 * Copyright 2012-2016, Connect2id Ltd.
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
007 * this file except in compliance with the License. You may obtain a copy of the
008 * License at
009 *
010 *    http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software distributed
013 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
014 * CONDITIONS OF ANY KIND, either express or implied. See the License for the
015 * specific language governing permissions and limitations under the License.
016 */
017
018package com.nimbusds.jose.crypto.bc;
019
020
021import org.bouncycastle.jce.provider.BouncyCastleProvider;
022
023import java.security.Provider;
024
025
026/**
027 * BouncyCastle JCA provider singleton, intended to prevent memory leaks by
028 * ensuring a single instance is loaded at all times. Application code that
029 * needs a BouncyCastle JCA provider should use the {@link #getInstance()}
030 * method to obtain an instance.
031 *
032 * <p>Requires the following optional dependency:
033 *
034 * <pre>
035 * &lt;dependency&gt;
036 *     &lt;groupId&gt;org.bouncycastle&lt;/groupId&gt;
037 *     &lt;artifactId&gt;bcprov-jdk15on&lt;/artifactId&gt;
038 *     &lt;version&gt;[1.68,2.0.0)&lt;/version&gt;
039 *     &lt;optional&gt;true&lt;/optional&gt;
040 * &lt;/dependency&gt;
041 * </pre>
042 *
043 * <p><strong>Important:</strong> The BouncyCastle FIPS JCA provider dependency
044 * must not be present to prevent class conflicts!
045 *
046 * @author Vladimir Dzhuvinov
047 * @version 2025-01-02
048 */
049public final class BouncyCastleProviderSingleton {
050
051
052        /**
053         * The BouncyCastle provider, lazily instantiated.
054         */
055        private static Provider bouncyCastleProvider;
056
057
058        /**
059         * Prevents external instantiation.
060         */
061        private BouncyCastleProviderSingleton() { }
062
063
064        /**
065         * Returns a BouncyCastle JCA provider instance.
066         *
067         * @return The BouncyCastle JCA provider instance.
068         */
069        public static Provider getInstance() {
070                
071                if (bouncyCastleProvider == null) {
072                        bouncyCastleProvider = new BouncyCastleProvider();
073                }
074                return bouncyCastleProvider;
075        }
076}