JAVA中IP和整数相互转化的方法
本文实例讲述了JAVA中IP和整数相互转化的方法。分享给大家供大家参考。具体分析如下：
一、基本知识点
IP——>整数：
把IP地址转化为字节数组
通过左移位（<<）、与（&）、或（|）这些操作转为int
整数——>IP：
将整数值进行右移位操作（>>>），右移24位，再进行与操作符（&）0xFF，得到的数字即为第一段IP。
将整数值进行右移位操作（>>>），右移16位，再进行与操作符（&）0xFF，得到的数字即为第二段IP。
将整数值进行右移位操作（>>>），右移8位，再进行与操作符（&）0xFF，得到的数字即为第三段IP。
将整数值进行与操作符（&）0xFF，得到的数字即为第四段IP。
二、java代码示例（IPv4Util.java）
packagemichael.utils;
importjava.net.InetAddress;
publicclassIPv4Util{
privatefinalstaticintINADDRSZ=4;
publicstaticbyte[]ipToBytesByInet(StringipAddr){
try{
returnInetAddress.getByName(ipAddr).getAddress();
}catch(Exceptione){
thrownewIllegalArgumentException(ipAddr+"isinvalidIP");
}
}JTA实践:Spring+ATOMIKOS
publicstaticbyte[]ipToBytesByReg(StringipAddr){
byte[]ret=newbyte[4];
try{
String[]ipArr=ipAddr.split("\\.");
ret[0]=(byte)(Integer.parseInt(ipArr[0])&0xFF);
ret[1]=(byte)(Integer.parseInt(ipArr[1])&0xFF);
ret[2]=(byte)(Integer.parseInt(ipArr[2])&0xFF);
ret[3]=(byte)(Integer.parseInt(ipArr[3])&0xFF);
returnret;
}catch(Exceptione){
thrownewIllegalArgumentException(ipAddr+"isinvalidIP");
}
}
publicstaticStringbytesToIp(byte[]bytes){
returnnewStringBuffer().append(bytes[0]&0xFF).append('.').append(
bytes[1]&0xFF).append('.').append(bytes[2]&0xFF)
.append('.').append(bytes[3]&0xFF).toString();
}
publicstaticintbytesToInt(byte[]bytes){
intaddr=bytes[3]&0xFF;
addr|=((bytes[2]<<8)&0xFF00);
addr|=((bytes[1]<<16)&0xFF0000);
addr|=((bytes[0]<<24)&0xFF000000);
returnaddr;
}
publicstaticintipToInt(StringipAddr){
try{
returnbytesToInt(ipToBytesByInet(ipAddr));
}catch(Exceptione){
thrownewIllegalArgumentException(ipAddr+"isinvalidIP");
}
}
publicstaticbyte[]intToBytes(intipInt){
byte[]ipAddr=newbyte[INADDRSZ];
ipAddr[0]=(byte)((ipInt>>>24)&0xFF);
ipAddr[1]=(byte)((ipInt>>>16)&0xFF);
ipAddr[2]=(byte)((ipInt>>>8)&0xFF);
ipAddr[3]=(byte)(ipInt&0xFF);
returnipAddr;
}
publicstaticStringintToIp(intipInt){
returnnewStringBuilder().append(((ipInt>>24)&0xff)).append('.')
.append((ipInt>>16)&0xff).append('.').append(
(ipInt>>8)&0xff).append('.').append((ipInt&0xff))
.toString();
}
publicstaticint[]getIPIntScope(StringipAndMask){
String[]ipArr=ipAndMask.split("/");
if(ipArr.length!=2){
thrownewIllegalArgumentException("invalidipAndMaskwith:"
+ipAndMask);
}
intnetMask=Integer.valueOf(ipArr[1].trim());
if(netMask<0||netMask>31){
thrownewIllegalArgumentException("invalidipAndMaskwith:"
+ipAndMask);
}
intipInt=IPv4Util.ipToInt(ipArr[0]);
intnetIP=ipInt&(0xFFFFFFFF<<(32-netMask));
inthostScope=(0xFFFFFFFF>>>netMask);
returnnewint[]{netIP,netIP+hostScope};
}
publicstaticString[]getIPAddrScope(StringipAndMask){
int[]ipIntArr=IPv4Util.getIPIntScope(ipAndMask);
returnnewString[]{IPv4Util.intToIp(ipIntArr[0]),
IPv4Util.intToIp(ipIntArr[0])};
}
publicstaticint[]getIPIntScope(StringipAddr,Stringmask){
intipInt;
intnetMaskInt=0,ipcount=0;
try{
ipInt=IPv4Util.ipToInt(ipAddr);
if(null==mask||"".equals(mask)){
returnnewint[]{ipInt,ipInt};
}
netMaskInt=IPv4Util.ipToInt(mask);
ipcount=IPv4Util.ipToInt("255.255.255.255")-netMaskInt;
intnetIP=ipInt&netMaskInt;
inthostScope=netIP+ipcount;
returnnewint[]{netIP,hostScope};
}catch(Exceptione){
thrownewIllegalArgumentException("invalidipscopeexpressip:"
+ipAddr+"mask:"+mask);
}
}
publicstaticString[]getIPStrScope(StringipAddr,Stringmask){
int[]ipIntArr=IPv4Util.getIPIntScope(ipAddr,mask);
returnnewString[]{IPv4Util.intToIp(ipIntArr[0]),
IPv4Util.intToIp(ipIntArr[0])};
}
publicstaticvoidmain(String[]args)throwsException{
StringipAddr="192.168.8.1";
byte[]bytearr=IPv4Util.ipToBytesByInet(ipAddr);
StringBufferbyteStr=newStringBuffer();
for(byteb:bytearr){
if(byteStr.length()==0){
byteStr.append(b);
}else{
byteStr.append(","+b);
}
}
System.out.println("IP:"+ipAddr+"ByInet-->byte[]:["+byteStr
+"]");
bytearr=IPv4Util.ipToBytesByReg(ipAddr);
byteStr=newStringBuffer();
for(byteb:bytearr){
if(byteStr.length()==0){
byteStr.append(b);
}else{
byteStr.append(","+b);
}
}
System.out.println("IP:"+ipAddr+"ByReg-->byte[]:["+byteStr
+"]");
System.out.println("byte[]:"+byteStr+"-->IP:"
+IPv4Util.bytesToIp(bytearr));
intipInt=IPv4Util.ipToInt(ipAddr);
System.out.println("IP:"+ipAddr+"-->int:"+ipInt);
System.out.println("int:"+ipInt+"-->IP:"
+IPv4Util.intToIp(ipInt));
StringipAndMask="192.168.1.1/24";
int[]ipscope=IPv4Util.getIPIntScope(ipAndMask);
System.out.println(ipAndMask+"-->int地址段：["+ipscope[0]+","
+ipscope[1]+"]");
System.out.println(ipAndMask+"-->IP地址段：["
+IPv4Util.intToIp(ipscope[0])+","
+IPv4Util.intToIp(ipscope[1])+"]");
StringipAddr1="192.168.1.1",ipMask1="255.255.255.0";
int[]ipscope1=IPv4Util.getIPIntScope(ipAddr1,ipMask1);
System.out.println(ipAddr1+","+ipMask1+"-->int地址段：["
+ipscope1[0]+","+ipscope1[1]+"]");
System.out.println(ipAddr1+","+ipMask1+"-->IP地址段：["
+IPv4Util.intToIp(ipscope1[0])+","
+IPv4Util.intToIp(ipscope1[1])+"]");
}
}
希望本文所述对大家的java程序设计有所帮助。