可以在每次生成随机字符串后输出当前的进度,示例代码如下:
```java
import java.math.BigInteger;
import java.util.HashSet;
import java.util.UUID;
public class RandomStringGenerator {
public static void main(String[] args) {
int count = 1000000;
HashSet set = new HashSet<>(count);
for (int i = 0; i < count; i++) {
String uuid = UUID.randomUUID().toString();
String hexString = uuid.replaceAll("-", "");
BigInteger bigInteger = new BigInteger(hexString, 16);
String randomString = bigInteger.toString(36).substring(0, 18);
set.add(randomString);
if ((i + 1) % 10000 == 0) {
System.out.println("Generated " + (i + 1) + " strings.");
}
}
System.out.println("Generated " + set.size() + " unique strings.");
}
}
```
这段代码会在每生成 1 万个随机字符串时输出当前的进度,最终输出实际生成的不重复字符串数量。