Generate short UUID

ShortUUID.java

import java.nio.ByteBuffer;
import java.util.UUID;

/**
 * Generate short UUID (13 characters)
 * 
 * @return short UUID
 */
public static String shortUUID() {
  UUID uuid = UUID.randomUUID();
  long l = ByteBuffer.wrap(uuid.toString().getBytes()).getLong();
  return Long.toString(l, Character.MAX_RADIX);
}

you are only using 64 out of the 128 bit, no? so this is not really a unique id anymore.

It is only less unique the UUID because the 128 bit is not uique as well.

As a one-liner:

String shortUUID = Long.toString(ByteBuffer.wrap(UUID.randomUUID().toString().getBytes()).getLong(), Character.MAX_RADIX);