java 生成UUID 40位
时间: 2023-10-05 11:12:42 浏览: 51
Java生成UUID的长度通常是36位,如果需要将其转换为40位,可以使用SHA-1等散列算法对UUID进行哈希运算,如下所示:
```java
import java.util.UUID;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class Test {
public static void main(String[] args) throws NoSuchAlgorithmException {
UUID uuid = UUID.randomUUID();
MessageDigest md = MessageDigest.getInstance("SHA-1");
md.update(uuid.toString().getBytes());
byte[] digest = md.digest();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < digest.length; i++) {
sb.append(Integer.toHexString((digest[i] & 0xFF) | 0x100).substring(1, 3));
}
System.out.println(sb.toString());
}
}
```
输出结果为40位的哈希值。