选择sha256解密和md5转换postgresql和java

时间:2018-09-19 19:30:04

标签: java postgresql md5 sha256

下午好,我需要将UUID转换为sha256,然后再转换为md5,在​​Java中它可以工作,但是如果我通过pgadmin(postgres)做到这一点,则1个字符不同

在Java中

public class outro {

public static void main(String[] args) {
    String prontuarioBaseUUID = "a1d347fc-094f-49de-91b9-f2765c58b94d";
    System.out.println(uuidSha2Encrypt(prontuarioBaseUUID));

}

public static String uuidSha2Encrypt(String uuid) {
    try {
        MessageDigest md = MessageDigest.getInstance("SHA-256");
        md.update(uuid.getBytes());
        return UUID.nameUUIDFromBytes(md.digest()).toString();
    } catch (NoSuchAlgorithmException ns) {
        throw new RuntimeException("Algoritmo SHA-256 não disponível", ns);
    }
}

结果 d5fabb45-dbd1-399b-a6c1-515367b8a2d4

在pgadmin postgres中

  

从tb_paciente中选择uuid_in(md5(digest('a1d347fc-094f-49de-91b9-f2765c58b94d','sha256')):: cstring)

结果 d5fabb45-dbd1-b99b-a6c1-515367b8a2d4

什么问题? thxx

  1. d5fabb45-dbd1- 399b -a6c1-515367b8a2d4
  2. d5fabb45-dbd1- b99b -a6c1-515367b8a2d4

1 个答案:

答案 0 :(得分:4)

您的Java方法有一个问题,因为它不包含UUID v3所需的名称空间。您需要在调用UUID.nameUUIDFromBytes之前在名称空间前添加名称:

private static final UUID NAMESPACE = UUID.fromString("00000000-0000-0000-0000-000000000000");

public static void main(String[] args) {
    // Charset should match SERVER_ENCODING
    System.out.println(uuidV3(NAMESPACE, "test".getBytes(StandardCharsets.UTF_8)));
}

public static UUID uuidV3(UUID namespace, byte[] name) {
    byte[] ns = toBytes(namespace);
    byte[] nsAndName = concatenate(ns, name);
    return UUID.nameUUIDFromBytes(nsAndName);
}

public static byte[] concatenate(byte[] a, byte[] b) {
    byte[] result = new byte[a.length + b.length];
    System.arraycopy(a, 0, result, 0, a.length);
    System.arraycopy(b, 0, result, a.length, b.length);
    return result;
}

public static byte[] toBytes(UUID uuid) {
    ByteBuffer buffer = ByteBuffer.wrap(new byte[16]);
    buffer.putLong(uuid.getMostSignificantBits());
    buffer.putLong(uuid.getLeastSignificantBits());
    return buffer.array();
}

在上面的示例中,我使用了nil命名空间,但是它可以是任何东西。

上面的测试打印

96e17d7a-ac89-38cf-95e1-bf5098da34e1

与等效的postgres查询的输出匹配:

select uuid_generate_v3(uuid_nil(), 'test');