java 根据ipv6/掩码获取所有ipv6

可以使用Java中的`InetAddress`类来实现。以下是一个示例代码，可以根据IPv6和掩码获取所有IPv6：

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;

public class IPv6Generator {
    public static List<String> getIPs(String ipv6, int mask) throws UnknownHostException {
        InetAddress inetAddress = InetAddress.getByName(ipv6);
        byte[] address = inetAddress.getAddress();

        // 将掩码转换为子网掩码
        int[] netmask = new int[address.length];
        for (int i = 0; i < address.length; i++) {
            if (mask >= 8) {
                netmask[i] = 255;
                mask -= 8;
            } else if (mask > 0) {
                netmask[i] = (int) (256 - Math.pow(2, 8 - mask));
                mask = 0;
            }
        }

        // 计算网络地址
        byte[] netaddress = new byte[address.length];
        for (int i = 0; i < address.length; i++) {
            netaddress[i] = (byte) (address[i] & netmask[i]);
        }

        // 生成所有地址
        List<String> ips = new ArrayList<>();
        for (int i = 0; i < Math.pow(2, 128 - mask); i++) {
            byte[] ip = new byte[16];
            int k = 15;
            for (int j = address.length - 1; j >= 0; j--) {
                if (k >= 0) {
                    if (mask >= 8) {
                        ip[k--] = netaddress[j];
                    } else if (mask > 0) {
                        ip[k--] = (byte) ((netaddress[j] & netmask[j]) + (i >>> (8 - mask)) & 0xFF);
                        mask = 0;
                    } else {
                        ip[k--] = (byte) (Math.random() * 256);
                    }
                } else {
                    break;
                }
            }
            ips.add(InetAddress.getByAddress(ip).getHostAddress());
        }

        return ips;
    }

    public static void main(String[] args) throws Exception {
        List<String> ips = getIPs("2001:db8::", 64);
        for (String ip : ips) {
            System.out.println(ip);
        }
    }
}

在上面的代码中，我们首先将IPv6地址和掩码转换为字节数组，然后计算网络地址。最后，我们生成所有IP地址并返回它们。

请注意，此代码仅生成IPv6地址，而不考虑IPv4映射地址。