[java]根据ip和掩码计算网段 广播地址及可用ip地址范围

ip地址与掩码、网段、广播地址、可用ip范围

IP： 网络地址掩码： 指明一个IP地址的哪些位标识的是主机所在的子网。网段：网络中可通信的部分，一般用子网第一个地址表示。广播地址：专门用于同时向网络中所有工作站进行发送的一个地址；一般用子网最后一个地址表示。可用子网ip：一般指子网中去除网段、广播地址的地址范围

参考资料：

子网划分

完整代码：

import java.util.HashMap;public class IpUtil {/*** 在main方法里面可以测试下 * 主要功能都在main方法里，需要什么自己找 */public static void main(String[] args) {String ip="192.168.1.21";//ipString mask="255.255.254.0";//位数，如果只知道子网掩码不知道位数的话在参考getMaskMap()方法NetInfo info = new NetInfo(ip,mask);System.out.println("ip:"+info.getIp());System.out.println("mask:"+info.getMask());System.out.println("broadcase:"+info.getBroadcast());System.out.println("segment:"+info.getSegment());System.out.println("startip:"+info.getStartIp());System.out.println("endIP:"+info.getEndIp());System.out.println("count:"+info.getCount());// System.out.println(getIpFromLong(getNetStartIp(ip,mask)));}/*** 输出二进制* @param n*/public static void binaryToDecimal(long n){for(int i = 63;i >= 0; i--) {System.out.print(n >>> i & 1);}System.out.println("---->");}/*** 把xx.xx.xx.xx类型的转为long类型的** @param ip* @return*/public static Long getIpFromString(String ip){// 进制 2^8 = 256 共四段Long ipLong = 0L;String ipTemp = ip;ipLong = ipLong * 256+ Long.parseLong(ipTemp.substring(0, ipTemp.indexOf('.')));ipTemp = ipTemp.substring(ipTemp.indexOf('.') + 1, ipTemp.length());ipLong = ipLong * 256+ Long.parseLong(ipTemp.substring(0, ipTemp.indexOf('.')));ipTemp = ipTemp.substring(ipTemp.indexOf(".") + 1, ipTemp.length());ipLong = ipLong * 256+ Long.parseLong(ipTemp.substring(0, ipTemp.indexOf('.')));ipTemp = ipTemp.substring(ipTemp.indexOf('.') + 1, ipTemp.length());ipLong = ipLong * 256 + Long.parseLong(ipTemp);return ipLong;}/*** 把long类型的Ip转为一般Ip类型：xx.xx.xx.xx** @param ip* @return*/public static String getIpFromLong(Long ip){String s1 = String.valueOf((ip & 4278190080L) / 16777216L); // 255.0.0.0 ~ 1.0.0.0 截取第一个八位String s2 = String.valueOf((ip & 16711680L) / 65536L); // 0.255.0.0 ~ 0.1.0.0 截取第二个八位String s3 = String.valueOf((ip & 65280L) / 256L); // 0.0.255.0 ~ 0.0.1.0 截取第三个八位String s4 = String.valueOf(ip & 255L); // 0.0.0.255 ~ 0.0.0.1 截取第四个八位return s1 + "." + s2 + "." + s3 + "." + s4;}public static class NetInfo{private static final long VALIDATE_DATA = Long.MAX_VALUE>>31;private static final HashMap<Integer,String> NET_MASK = new HashMap<>();private static String IP_REGEX = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."+ "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\." +"(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."+ "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";// ipprivate String ipStr;private Long ip;// 掩码private String maskStr;private Long mask;// 网段private String segmentStr;private Long segment;// 广播地址private String broadcastStr;private Long broadcast;// 开始ipprivate String startIpStr;private Long startIp;// 结束ipprivate String endIpStr;private Long endIp;// 可用ip数private Long count;// 初始化掩码static{NET_MASK.put(32,getIpFromLong(VALIDATE_DATA));for(int i=1;i<32;i++) {NET_MASK.put(32-i,getIpFromLong(VALIDATE_DATA << i & VALIDATE_DATA));}}public NetInfo(String ipStr, String maskStr) {this.ipStr = ipStr;this.maskStr = maskStr;checkParam();init();}public NetInfo(String ipStr, int mask) {this(ipStr,NET_MASK.get(mask));}public void checkParam(){if(maskStr == null|| "".equals(maskStr.trim())|| !NET_MASK.containsValue(maskStr)){throw new RuntimeException("掩码无效");}if(ipStr == null || "".equals(ipStr.trim())){throw new RuntimeException("ip地址为空");}// 判断ip地址是否与正则表达式匹配if (!ipStr.matches(IP_REGEX)) {throw new RuntimeException("IP地址不合规范");}}public void init(){this.ip = getIpFromString(ipStr);this.mask = getIpFromString(maskStr);// 网段 = ip & 掩码this.segment = this.ip & this.mask;this.segmentStr = getIpFromLong(this.segment);// 广播地址 网段末尾用1补齐this.broadcast = this.segment | (~this.mask & VALIDATE_DATA);binaryToDecimal(broadcast);this.broadcastStr = getIpFromLong(this.broadcast);// 开始地址 网段+1this.startIp = this.segment +1;this.startIpStr = getIpFromLong(this.startIp);// 结束地址 广播地址-1this.endIp = this.broadcast -1;this.endIpStr = getIpFromLong(this.endIp);/*for( long i = startIp;i< endIp;i++){System.out.println(getIpFromLong(i + 1));}*/this.count = this.broadcast - this.startIp;}public String getIp() {return ipStr;}public String getMask() {return maskStr;}public String getSegment() {return segmentStr;}public String getBroadcast() {return broadcastStr;}public String getStartIp() {return startIpStr;}public String getEndIp() {return endIpStr;}public Long getCount() {return count;}}}