java – 将uuid转换为字节,当使用UUID.nameUUIDFromBytes(b)
发布时间:2020-12-14 16:18:16 所属栏目:Java 来源:网络整理
导读:我使用此代码将UUID转换为字节 public byte[] getIdAsByte(UUID uuid){ ByteBuffer bb = ByteBuffer.wrap(new byte[16]); bb.putLong(uuid.getMostSignificantBits()); bb.putLong(uuid.getLeastSignificantBits()); return bb.array();} 但是,如果我尝试使
我使用此代码将UUID转换为字节
public byte[] getIdAsByte(UUID uuid) { ByteBuffer bb = ByteBuffer.wrap(new byte[16]); bb.putLong(uuid.getMostSignificantBits()); bb.putLong(uuid.getLeastSignificantBits()); return bb.array(); } 但是,如果我尝试使用此功能重新创建UUID, public UUID frombyte(byte[] b) { return UUID.nameUUIDFromBytes(b); } 这是不一样的UUID.转换一个randomUUID来回返回两个不同的. UUID u = UUID.randomUUID(); System.out.println(u.toString()); System.out.println(frombyte(getIdAsByte(u)).toString()); 打印: 1ae004cf-0f48-469f-8a94-01339afaec41 8b5d1a71-a4a0-3b46-bec3-13ab9ab12e8e 解决方法public class UuidUtils { public static UUID asUuid(byte[] bytes) { ByteBuffer bb = ByteBuffer.wrap(bytes); long firstLong = bb.getLong(); long secondLong = bb.getLong(); return new UUID(firstLong,secondLong); } public static byte[] asBytes(UUID uuid) { ByteBuffer bb = ByteBuffer.wrap(new byte[16]); bb.putLong(uuid.getMostSignificantBits()); bb.putLong(uuid.getLeastSignificantBits()); return bb.array(); } } @Test public void verifyUUIDBytesCanBeReconstructedBackToOriginalUUID() { UUID u = UUID.randomUUID(); byte[] uBytes = UuidUtils.asBytes(u); UUID u2 = UuidUtils.asUuid(uBytes); Assert.assertEquals(u,u2); } @Test public void verifyNameUUIDFromBytesMethodDoesNotRecreateOriginalUUID() { UUID u = UUID.randomUUID(); byte[] uBytes = UuidUtils.asBytes(u); UUID u2 = UUID.nameUUIDFromBytes(uBytes); Assert.assertNotEquals(u,u2); } (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |