IP网段拆分出多个IP

package com.lzk.test01.test;

import lombok.extern.slf4j.Slf4j;

import java.io.*;

@Slf4j
public class IpTest1 {
    public static void main(String[] args) throws Exception {
        String demo = "1.0.1.5-2.0.2.4";
        String[] split = demo.split("-");
        String ip1 = split[0];
        String ip2 = split[1];
        //todo 校验ip格式
        if (ip1.equals(ip2)) {
            System.out.println("ip网段不能相同");
        }
        String[] split1 = ip1.split("\\.");
        String[] split2 = ip2.split("\\.");
        int aNum = 0, bNum = 0, cNum = 0, dNum = 0;
        boolean aBoolean = split1[0].equals(split2[0]);
        boolean bBoolean = split1[1].equals(split2[1]);
        boolean cBoolean = split1[2].equals(split2[2]);
        boolean dBoolean = split1[3].equals(split2[3]);
        int a1 = Integer.parseInt(split1[0]);
        int a2 = Integer.parseInt(split2[0]);
        int b1 = Integer.parseInt(split1[1]);
        int b2 = Integer.parseInt(split2[1]);
        int c1 = Integer.parseInt(split1[2]);
        int c2 = Integer.parseInt(split2[2]);
        int d1 = Integer.parseInt(split1[3]);
        int d2 = Integer.parseInt(split2[3]);
        if (!aBoolean) {
            if (a1 > a2) {
                throw new Exception("ip网段必须从小到大");
            }
            aNum = a2 - a1 + 1;
        }
        if (!bBoolean && aBoolean) {
            if (b1 > b2) {
                throw new Exception("ip网段必须从小到大");
            }
            bNum = b2 - b1 + 1;
        }
        if(aNum > 0){
            bNum = 256;
        }
        if (!cBoolean && aBoolean && bBoolean) {
            if (c1 > c2) {
                throw new Exception("ip网段必须从小到大");
            }
            cNum = c2 - c1 + 1;
        }
        if (!dBoolean && aBoolean && bBoolean && cBoolean) {
            if (d1 > d2) {
                throw new Exception("ip网段必须从小到大");
            }
        }
        if(bNum > 0){
            cNum = 256;
        }
        if (aNum == 0) {
            aNum = 1;
        }
        if (bNum == 0) {
            bNum = 1;
        }
        if (cNum == 0) {
            cNum = 1;
        }
        try {
            File file = new File("ip.txt");
            file.createNewFile();
            FileWriter fileWriter = new FileWriter(file);
            BufferedWriter out = new BufferedWriter(fileWriter);
            out.write(ip1 + "\r\n");
            boolean flag = false;
            for (int n = 0; n < aNum; n++) {
                if(flag){
                    break;
                }
                for (int i = 0; i < bNum; i++) {
                    if(flag){
                        break;
                    }
                    for (int j = 0; j < cNum; j++) {
                        if(flag){
                            break;
                        }
                        for (int k = 0; k < 256; k++) {
                            d1++;
                            if (d1 == 256) {
                                c1 ++;
                                d1 = 0;
                            }
                            if (c1 == 256) {
                                b1 ++;
                                c1 = 0;
                            }
                            if (b1 == 256) {
                                a1 ++;
                                b1 = 0;
                            }
                            if (a1 > 255) {
                                a1 = 255;
                            }
                            String s = a1 + "." + b1 + "." + c1 + "." + d1;
                            if (s.equals(ip2)) {
                                log.info(a1 + "." + b1 + "." + c1 + "." + d1);
                                out.write(a1 + "." + b1 + "." + c1 + "." + d1 + "\r\n");
                                flag = true;
                                break;
                            }
                            log.info(a1 + "." + b1 + "." + c1 + "." + d1);
                            out.write(a1 + "." + b1 + "." + c1 + "." + d1 + "\r\n");
                        }
                    }
                }
            }
            out.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
        System.out.println("结束");
    }
}