/*
 * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
 * 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
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package sun.security.util;

import java.util.List;
import java.util.Locale;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;

This utility class maps algorithm name to the corresponding oid strings.
NOTE: for 100% backward compatibility, the standard name for the enum
is determined by existing usage and may be in lowercase/uppercase in
order to match existing output.
/**
 * This utility class maps algorithm name to the corresponding oid strings.
 * NOTE: for 100% backward compatibility, the standard name for the enum
 * is determined by existing usage and may be in lowercase/uppercase in
 * order to match existing output.
 */
public enum KnownOIDs {

    // X.500 Attributes 2.5.4.*
    CommonName("2.5.4.3"),
    Surname("2.5.4.4"),
    SerialNumber("2.5.4.5"),
    CountryName("2.5.4.6"),
    LocalityName("2.5.4.7"),
    StateName("2.5.4.8"),
    StreetAddress("2.5.4.9"),
    OrgName("2.5.4.10"),
    OrgUnitName("2.5.4.11"),
    Title("2.5.4.12"),
    GivenName("2.5.4.42"),
    Initials("2.5.4.43"),
    GenerationQualifier("2.5.4.44"),
    DNQualifier("2.5.4.46"),

    // Certificate Extension 2.5.29.*
    SubjectDirectoryAttributes("2.5.29.9"),
    SubjectKeyID("2.5.29.14"),
    KeyUsage("2.5.29.15"),
    PrivateKeyUsage("2.5.29.16"),
    SubjectAlternativeName("2.5.29.17"),
    IssuerAlternativeName("2.5.29.18"),
    BasicConstraints("2.5.29.19"),
    CRLNumber("2.5.29.20"),
    ReasonCode("2.5.29.21"),
    HoldInstructionCode("2.5.29.23"),
    InvalidityDate("2.5.29.24"),
    DeltaCRLIndicator("2.5.29.27"),
    IssuingDistributionPoint("2.5.29.28"),
    CertificateIssuer("2.5.29.29"),
    NameConstraints("2.5.29.30"),
    CRLDistributionPoints("2.5.29.31"),
    CertificatePolicies("2.5.29.32"),
    CE_CERT_POLICIES_ANY("2.5.29.32.0"),
    PolicyMappings("2.5.29.33"),
    AuthorityKeyID("2.5.29.35"),
    PolicyConstraints("2.5.29.36"),
    extendedKeyUsage("2.5.29.37"),
    anyExtendedKeyUsage("2.5.29.37.0"),
    FreshestCRL("2.5.29.46"),
    InhibitAnyPolicy("2.5.29.54"),

    // PKIX 1.3.6.1.5.5.7.
    AuthInfoAccess("1.3.6.1.5.5.7.1.1"),
    SubjectInfoAccess("1.3.6.1.5.5.7.1.11"),
    // key usage purposes - PKIX.3.*
    serverAuth("1.3.6.1.5.5.7.3.1"),
    clientAuth("1.3.6.1.5.5.7.3.2"),
    codeSigning("1.3.6.1.5.5.7.3.3"),
    emailProtection("1.3.6.1.5.5.7.3.4"),
    ipsecEndSystem("1.3.6.1.5.5.7.3.5"),
    ipsecTunnel("1.3.6.1.5.5.7.3.6"),
    ipsecUser("1.3.6.1.5.5.7.3.7"),
    KP_TimeStamping("1.3.6.1.5.5.7.3.8", "timeStamping") {
        @Override
        boolean registerNames() { return false; }
    },
    OCSPSigning("1.3.6.1.5.5.7.3.9"),
    // access descriptors - PKIX.48.*
    OCSP("1.3.6.1.5.5.7.48.1"),
    OCSPBasicResponse("1.3.6.1.5.5.7.48.1.1"),
    OCSPNonceExt("1.3.6.1.5.5.7.48.1.2"),
    OCSPNoCheck("1.3.6.1.5.5.7.48.1.5"),
    caIssuers("1.3.6.1.5.5.7.48.2"),
    AD_TimeStamping("1.3.6.1.5.5.7.48.3", "timeStamping") {
        @Override
        boolean registerNames() { return false; }
    },
    caRepository("1.3.6.1.5.5.7.48.5", "caRepository"),

    // NIST --
    // AES 2.16.840.1.101.3.4.1.*
    AES("2.16.840.1.101.3.4.1"),
    AES_128$ECB$NoPadding("2.16.840.1.101.3.4.1.1", "AES_128/ECB/NoPadding"),
    AES_128$CBC$NoPadding("2.16.840.1.101.3.4.1.2", "AES_128/CBC/NoPadding"),
    AES_128$OFB$NoPadding("2.16.840.1.101.3.4.1.3", "AES_128/OFB/NoPadding"),
    AES_128$CFB$NoPadding("2.16.840.1.101.3.4.1.4", "AES_128/CFB/NoPadding"),
    AESWRAP_128("2.16.840.1.101.3.4.1.5"),
    AES_128$GCM$NoPadding("2.16.840.1.101.3.4.1.6", "AES_128/GCM/NoPadding"),
    AES_192$ECB$NoPadding("2.16.840.1.101.3.4.1.21", "AES_192/ECB/NoPadding"),
    AES_192$CBC$NoPadding("2.16.840.1.101.3.4.1.22", "AES_192/CBC/NoPadding"),
    AES_192$OFB$NoPadding("2.16.840.1.101.3.4.1.23", "AES_192/OFB/NoPadding"),
    AES_192$CFB$NoPadding("2.16.840.1.101.3.4.1.24", "AES_192/CFB/NoPadding"),
    AESWRAP_192("2.16.840.1.101.3.4.1.25"),
    AES_192$GCM$NoPadding("2.16.840.1.101.3.4.1.26", "AES_192/GCM/NoPadding"),
    AES_256$ECB$NoPadding("2.16.840.1.101.3.4.1.41", "AES_256/ECB/NoPadding"),
    AES_256$CBC$NoPadding("2.16.840.1.101.3.4.1.42", "AES_256/CBC/NoPadding"),
    AES_256$OFB$NoPadding("2.16.840.1.101.3.4.1.43", "AES_256/OFB/NoPadding"),
    AES_256$CFB$NoPadding("2.16.840.1.101.3.4.1.44", "AES_256/CFB/NoPadding"),
    AESWRAP_256("2.16.840.1.101.3.4.1.45"),
    AES_256$GCM$NoPadding("2.16.840.1.101.3.4.1.46", "AES_256/GCM/NoPadding"),

    // hashAlgs 2.16.840.1.101.3.4.2.*
    SHA_256("2.16.840.1.101.3.4.2.1", "SHA-256", "SHA256"),
    SHA_384("2.16.840.1.101.3.4.2.2", "SHA-384", "SHA384"),
    SHA_512("2.16.840.1.101.3.4.2.3", "SHA-512", "SHA512"),
    SHA_224("2.16.840.1.101.3.4.2.4", "SHA-224", "SHA224"),
    SHA_512$224("2.16.840.1.101.3.4.2.5", "SHA-512/224", "SHA512/224"),
    SHA_512$256("2.16.840.1.101.3.4.2.6", "SHA-512/256", "SHA512/256"),
    SHA3_224("2.16.840.1.101.3.4.2.7", "SHA3-224"),
    SHA3_256("2.16.840.1.101.3.4.2.8", "SHA3-256"),
    SHA3_384("2.16.840.1.101.3.4.2.9", "SHA3-384"),
    SHA3_512("2.16.840.1.101.3.4.2.10", "SHA3-512"),
    SHAKE128("2.16.840.1.101.3.4.2.11"),
    SHAKE256("2.16.840.1.101.3.4.2.12"),
    HmacSHA3_224("2.16.840.1.101.3.4.2.13", "HmacSHA3-224"),
    HmacSHA3_256("2.16.840.1.101.3.4.2.14", "HmacSHA3-256"),
    HmacSHA3_384("2.16.840.1.101.3.4.2.15", "HmacSHA3-384"),
    HmacSHA3_512("2.16.840.1.101.3.4.2.16", "HmacSHA3-512"),

    // sigAlgs 2.16.840.1.101.3.4.3.*
    SHA224withDSA("2.16.840.1.101.3.4.3.1"),
    SHA256withDSA("2.16.840.1.101.3.4.3.2"),
    SHA384withDSA("2.16.840.1.101.3.4.3.3"),
    SHA512withDSA("2.16.840.1.101.3.4.3.4"),
    SHA3_224withRSA("2.16.840.1.101.3.4.3.13", "SHA3-224withRSA"),
    SHA3_256withRSA("2.16.840.1.101.3.4.3.14", "SHA3-256withRSA"),
    SHA3_384withRSA("2.16.840.1.101.3.4.3.15", "SHA3-384withRSA"),
    SHA3_512withRSA("2.16.840.1.101.3.4.3.16", "SHA3-512withRSA"),

    // RSASecurity
    // PKCS1 1.2.840.113549.1.1.*
    PKCS1("1.2.840.113549.1.1", "RSA") { // RSA KeyPairGenerator and KeyFactory
        @Override
        boolean registerNames() { return false; }
    },
    RSA("1.2.840.113549.1.1.1"), // RSA encryption

    MD2withRSA("1.2.840.113549.1.1.2"),
    MD5withRSA("1.2.840.113549.1.1.4"),
    SHA1withRSA("1.2.840.113549.1.1.5"),
    OAEP("1.2.840.113549.1.1.7"),
    MGF1("1.2.840.113549.1.1.8"),
    PSpecified("1.2.840.113549.1.1.9"),
    RSASSA_PSS("1.2.840.113549.1.1.10", "RSASSA-PSS"),
    SHA256withRSA("1.2.840.113549.1.1.11"),
    SHA384withRSA("1.2.840.113549.1.1.12"),
    SHA512withRSA("1.2.840.113549.1.1.13"),
    SHA224withRSA("1.2.840.113549.1.1.14"),
    SHA512$224withRSA("1.2.840.113549.1.1.15", "SHA512/224withRSA"),
    SHA512$256withRSA("1.2.840.113549.1.1.16", "SHA512/256withRSA"),

    // PKCS3 1.2.840.113549.1.3.*
    DiffieHellman("1.2.840.113549.1.3.1", "DiffieHellman", "DH"),

    // PKCS5 1.2.840.113549.1.5.*
    PBEWithMD5AndDES("1.2.840.113549.1.5.3"),
    PBEWithMD5AndRC2("1.2.840.113549.1.5.6"),
    PBEWithSHA1AndDES("1.2.840.113549.1.5.10"),
    PBEWithSHA1AndRC2("1.2.840.113549.1.5.11"),
    PBKDF2WithHmacSHA1("1.2.840.113549.1.5.12"),
    PBES2("1.2.840.113549.1.5.13"),

    // PKCS7 1.2.840.113549.1.7.*
    PKCS7("1.2.840.113549.1.7"),
    Data("1.2.840.113549.1.7.1"),
    SignedData("1.2.840.113549.1.7.2"),
    JDK_OLD_Data("1.2.840.1113549.1.7.1"), // extra 1 in 4th component
    JDK_OLD_SignedData("1.2.840.1113549.1.7.2"),
    EnvelopedData("1.2.840.113549.1.7.3"),
    SignedAndEnvelopedData("1.2.840.113549.1.7.4"),
    DigestedData("1.2.840.113549.1.7.5"),
    EncryptedData("1.2.840.113549.1.7.6"),

    // PKCS9 1.2.840.113549.1.9.*
    EmailAddress("1.2.840.113549.1.9.1"),
    UnstructuredName("1.2.840.113549.1.9.2"),
    ContentType("1.2.840.113549.1.9.3"),
    MessageDigest("1.2.840.113549.1.9.4"),
    SigningTime("1.2.840.113549.1.9.5"),
    CounterSignature("1.2.840.113549.1.9.6"),
    ChallengePassword("1.2.840.113549.1.9.7"),
    UnstructuredAddress("1.2.840.113549.1.9.8"),
    ExtendedCertificateAttributes("1.2.840.113549.1.9.9"),
    IssuerAndSerialNumber("1.2.840.113549.1.9.10"),
    ExtensionRequest("1.2.840.113549.1.9.14"),
    SMIMECapability("1.2.840.113549.1.9.15"),
    TimeStampTokenInfo("1.2.840.113549.1.9.16.1.4"),
    SigningCertificate("1.2.840.113549.1.9.16.2.12"),
    SignatureTimestampToken("1.2.840.113549.1.9.16.2.14"),
    CHACHA20_POLY1305("1.2.840.113549.1.9.16.3.18", "CHACHA20-POLY1305"),
    FriendlyName("1.2.840.113549.1.9.20"),
    LocalKeyID("1.2.840.113549.1.9.21"),
    CertTypeX509("1.2.840.113549.1.9.22.1"),

    // PKCS12 1.2.840.113549.1.12.*
    PBEWithSHA1AndRC4_128("1.2.840.113549.1.12.1.1"),
    PBEWithSHA1AndRC4_40("1.2.840.113549.1.12.1.2"),
    PBEWithSHA1AndDESede("1.2.840.113549.1.12.1.3"),
    PBEWithSHA1AndRC2_128("1.2.840.113549.1.12.1.5"),
    PBEWithSHA1AndRC2_40("1.2.840.113549.1.12.1.6"),
    PKCS8ShroudedKeyBag("1.2.840.113549.1.12.10.1.2"),
    CertBag("1.2.840.113549.1.12.10.1.3"),
    SecretBag("1.2.840.113549.1.12.10.1.5"),

    // digestAlgs 1.2.840.113549.2.*
    MD2("1.2.840.113549.2.2"),
    MD5("1.2.840.113549.2.5"),
    HmacSHA1("1.2.840.113549.2.7"),
    HmacSHA224("1.2.840.113549.2.8"),
    HmacSHA256("1.2.840.113549.2.9"),
    HmacSHA384("1.2.840.113549.2.10"),
    HmacSHA512("1.2.840.113549.2.11"),
    HmacSHA512$224("1.2.840.113549.2.12", "HmacSHA512/224"),
    HmacSHA512$256("1.2.840.113549.2.13", "HmacSHA512/256"),

    // encryptionAlgs 1.2.840.113549.3.*
    RC2$CBC$PKCS5Padding("1.2.840.113549.3.2", "RC2/CBC/PKCS5Padding"),
    ARCFOUR("1.2.840.113549.3.4", "ARCFOUR", "RC4"),
    DESede$CBC$NoPadding("1.2.840.113549.3.7", "DESede/CBC/NoPadding"),
    RC5$CBC$PKCS5Padding("1.2.840.113549.3.9", "RC5/CBC/PKCS5Padding"),

    // ANSI --
    // X9 1.2.840.10040.4.*
    DSA("1.2.840.10040.4.1"),
    SHA1withDSA("1.2.840.10040.4.3", "SHA1withDSA", "DSS"),
    // X9.62 1.2.840.10045.*
    EC("1.2.840.10045.2.1"),

    //c2pnb163v1("1.2.840.10045.3.0.1", "X9.62 c2pnb163v1"),
    //c2pnb163v2("1.2.840.10045.3.0.2", "X9.62 c2pnb163v2"),
    //c2pnb163v3("1.2.840.10045.3.0.3", "X9.62 c2pnb163v3"),
    //c2pnb176w1("1.2.840.10045.3.0.4", "X9.62 c2pnb176w1"),
    c2tnb191v1("1.2.840.10045.3.0.5", "X9.62 c2tnb191v1"),
    c2tnb191v2("1.2.840.10045.3.0.6", "X9.62 c2tnb191v2"),
    c2tnb191v3("1.2.840.10045.3.0.7", "X9.62 c2tnb191v3"),
    //c2pnb208w1("1.2.840.10045.3.0.10", "X9.62 c2pnb208w1"),
    c2tnb239v1("1.2.840.10045.3.0.11", "X9.62 c2tnb239v1"),
    c2tnb239v2("1.2.840.10045.3.0.12", "X9.62 c2tnb239v2"),
    c2tnb239v3("1.2.840.10045.3.0.13", "X9.62 c2tnb239v3"),
    //c2pnb272w1("1.2.840.10045.3.0.16", "X9.62 c2pnb272w1"),
    //c2pnb304w1("1.2.840.10045.3.0.17", "X9.62 c2pnb304w1"),
    c2tnb359v1("1.2.840.10045.3.0.18", "X9.62 c2tnb359v1"),
    //c2pnb368w1("1.2.840.10045.3.0.19", "X9.62 c2pnb368w1"),
    c2tnb431r1("1.2.840.10045.3.0.20", "X9.62 c2tnb431r1"),

    secp192r1("1.2.840.10045.3.1.1",
            "secp192r1", "NIST P-192", "X9.62 prime192v1"),
    prime192v2("1.2.840.10045.3.1.2", "X9.62 prime192v2"),
    prime192v3("1.2.840.10045.3.1.3", "X9.62 prime192v3"),
    prime239v1("1.2.840.10045.3.1.4", "X9.62 prime239v1"),
    prime239v2("1.2.840.10045.3.1.5", "X9.62 prime239v2"),
    prime239v3("1.2.840.10045.3.1.6", "X9.62 prime239v3"),
    secp256r1("1.2.840.10045.3.1.7",
            "secp256r1", "NIST P-256", "X9.62 prime256v1"),
    SHA1withECDSA("1.2.840.10045.4.1"),
    SHA224withECDSA("1.2.840.10045.4.3.1"),
    SHA256withECDSA("1.2.840.10045.4.3.2"),
    SHA384withECDSA("1.2.840.10045.4.3.3"),
    SHA512withECDSA("1.2.840.10045.4.3.4"),
    SpecifiedSHA2withECDSA("1.2.840.10045.4.3"),

    // X9.42 1.2.840.10046.2.*
    X942_DH("1.2.840.10046.2.1", "DiffieHellman") { // unused by JDK providers
        @Override
        boolean registerNames() { return false; }
    },

    // Teletrust 1.3.36.*
    brainpoolP160r1("1.3.36.3.3.2.8.1.1.1"),
    brainpoolP192r1("1.3.36.3.3.2.8.1.1.3"),
    brainpoolP224r1("1.3.36.3.3.2.8.1.1.5"),
    brainpoolP256r1("1.3.36.3.3.2.8.1.1.7"),
    brainpoolP320r1("1.3.36.3.3.2.8.1.1.9"),
    brainpoolP384r1("1.3.36.3.3.2.8.1.1.11"),
    brainpoolP512r1("1.3.36.3.3.2.8.1.1.13"),

    // Certicom 1.3.132.*
    sect163k1("1.3.132.0.1", "sect163k1", "NIST K-163"),
    sect163r1("1.3.132.0.2"),
    sect239k1("1.3.132.0.3"),
    sect113r1("1.3.132.0.4"),
    sect113r2("1.3.132.0.5"),
    secp112r1("1.3.132.0.6"),
    secp112r2("1.3.132.0.7"),
    secp160r1("1.3.132.0.8"),
    secp160k1("1.3.132.0.9"),
    secp256k1("1.3.132.0.10"),
    sect163r2("1.3.132.0.15", "sect163r2", "NIST B-163"),
    sect283k1("1.3.132.0.16", "sect283k1", "NIST K-283"),
    sect283r1("1.3.132.0.17", "sect283r1", "NIST B-283"),

    sect131r1("1.3.132.0.22"),
    sect131r2("1.3.132.0.23"),
    sect193r1("1.3.132.0.24"),
    sect193r2("1.3.132.0.25"),
    sect233k1("1.3.132.0.26", "sect233k1", "NIST K-233"),
    sect233r1("1.3.132.0.27", "sect233r1", "NIST B-233"),
    secp128r1("1.3.132.0.28"),
    secp128r2("1.3.132.0.29"),
    secp160r2("1.3.132.0.30"),
    secp192k1("1.3.132.0.31"),
    secp224k1("1.3.132.0.32"),
    secp224r1("1.3.132.0.33", "secp224r1", "NIST P-224"),
    secp384r1("1.3.132.0.34", "secp384r1", "NIST P-384"),
    secp521r1("1.3.132.0.35", "secp521r1", "NIST P-521"),
    sect409k1("1.3.132.0.36", "sect409k1", "NIST K-409"),
    sect409r1("1.3.132.0.37", "sect409r1", "NIST B-409"),
    sect571k1("1.3.132.0.38", "sect571k1", "NIST K-571"),
    sect571r1("1.3.132.0.39", "sect571r1", "NIST B-571"),

    ECDH("1.3.132.1.12"),

    // OIW secsig 1.3.14.3.*
    OIW_DES_CBC("1.3.14.3.2.7", "DES/CBC"),

    OIW_DSA("1.3.14.3.2.12", "DSA") {
        @Override
        boolean registerNames() { return false; }
    },

    OIW_JDK_SHA1withDSA("1.3.14.3.2.13", "SHA1withDSA") {
        @Override
        boolean registerNames() { return false; }
    },

    OIW_SHA1withRSA_Odd("1.3.14.3.2.15", "SHA1withRSA") {
        @Override
        boolean registerNames() { return false; }
    },

    SHA_1("1.3.14.3.2.26", "SHA-1", "SHA", "SHA1"),

    OIW_SHA1withDSA("1.3.14.3.2.27", "SHA1withDSA") {
        @Override
        boolean registerNames() { return false; }
    },

    OIW_SHA1withRSA("1.3.14.3.2.29", "SHA1withRSA") {
        @Override
        boolean registerNames() { return false; }
    },

    // Thawte 1.3.101.*
    X25519("1.3.101.110"),
    X448("1.3.101.111"),
    Ed25519("1.3.101.112"),
    Ed448("1.3.101.113"),

    // University College London (UCL) 0.9.2342.19200300.*
    UCL_UserID("0.9.2342.19200300.100.1.1"),
    UCL_DomainComponent("0.9.2342.19200300.100.1.25"),

    // Netscape 2.16.840.1.113730.*
    NETSCAPE_CertType("2.16.840.1.113730.1.1"),
    NETSCAPE_CertSequence("2.16.840.1.113730.2.5"),
    NETSCAPE_ExportApproved("2.16.840.1.113730.4.1"),

    // Oracle 2.16.840.1.113894.*
    ORACLE_TrustedKeyUsage("2.16.840.1.113894.746875.1.1"),

    // Miscellaneous oids below which are legacy, and not well known
    // Consider removing them in future releases when their usage
    // have died out

    ITUX509_RSA("2.5.8.1.1", "RSA") { // unused by JDK providers
                                      // defined in X.509 for RSA keys
        @Override                     // with modulus length as its parameter
        boolean registerNames() { return false; }
    },

    SkipIPAddress("1.3.6.1.4.1.42.2.11.2.1"),
    JAVASOFT_JDKKeyProtector("1.3.6.1.4.1.42.2.17.1.1"),
    JAVASOFT_JCEKeyProtector("1.3.6.1.4.1.42.2.19.1"),
    MICROSOFT_ExportApproved("1.3.6.1.4.1.311.10.3.3");

    private String stdName;
    private String oid;
    private String[] aliases;

    // find the matching enum using either name or oid string
    // return null if no match found
    public static KnownOIDs findMatch(String s) {
        s = s.toUpperCase(Locale.ENGLISH);
        KnownOIDs res = name2enum.get(s);
        if (res == null && debug != null) {
            debug.println("No KnownOIDs enum found for " + s);
        }
        return res;
    }

    private static final Debug debug = Debug.getInstance("jca");
    //private static final java.io.PrintStream debug = System.out;
    private static final ConcurrentHashMap<String, KnownOIDs> name2enum =
            new ConcurrentHashMap<>();

    static {
        if (debug != null) {
            debug.println("Setting up name2enum:");
        }
        List.of(KnownOIDs.values()).forEach(o -> {
            register(o);
        });
    }

    private static void register(KnownOIDs o) {
        KnownOIDs ov = name2enum.put(o.oid, o);
        if (ov != null) {
            throw new RuntimeException("ERROR: Duplicate " + o.oid +
                    " between " + o + " and " + ov);
        } else if (debug != null) {
            debug.println(o.oid + " => " + o.name());
        }
        // only register the stdName and aliases if o.registerNames()
        // returns true
        if (o.registerNames()) {
            String stdNameUpper = o.stdName.toUpperCase(Locale.ENGLISH);
            if (Objects.nonNull(name2enum.put(stdNameUpper, o))) {
                throw new RuntimeException("ERROR: Duplicate " +
                        stdNameUpper + " exists already");
            }
            if (debug != null) {
                debug.println(stdNameUpper + " => " + o.name());
            }

            for (String a :  o.aliases) {
                String aliasUpper = a.toUpperCase(Locale.ENGLISH);
                if (Objects.nonNull(name2enum.put(aliasUpper, o))) {
                    throw new RuntimeException("ERROR: Duplicate " +
                            aliasUpper + " exists already");
                }
                if (debug != null) {
                    debug.println(aliasUpper + " => " + o.name());
                }
            }
        }
    }

    private KnownOIDs(String oid) {
        this.oid = oid;
        this.stdName = name(); // defaults to enum name
        this.aliases = new String[0];
    }

    private KnownOIDs(String oid, String stdName, String ... aliases) {
        this.oid = oid;
        this.stdName = stdName;
        this.aliases = aliases;
    }

    // returns the oid string associated with this enum
    public String value() {
        return oid;
    }

    // returns the user-friendly standard algorithm name
    public String stdName() {
        return stdName;
    }

    // return the internal aliases
    public String[] aliases() {
        return aliases;
    }

    boolean registerNames() {
        return true;
    }
}