JAVA中IP和整数相互转化的方法

package michael.utils; import java.net.InetAddress; public class IPv4Util {  private final static int INADDRSZ = 4;  public static byte[] ipToBytesByInet(String ipAddr) {   try {    return InetAddress.getByName(ipAddr).getAddress();   } catch (Exception e) {    throw new IllegalArgumentException(ipAddr + " is invalid IP");   }  }JTA实践:Spring+ATOMIKOS  public static byte[] ipToBytesByReg(String ipAddr) {   byte[] ret = new byte[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);    return ret;   } catch (Exception e) {    throw new IllegalArgumentException(ipAddr + " is invalid IP");   }  }  public static String bytesToIp(byte[] bytes) {   return new StringBuffer().append(bytes[0] & 0xFF).append('.').append(     bytes[1] & 0xFF).append('.').append(bytes[2] & 0xFF)     .append('.').append(bytes[3] & 0xFF).toString();  }  public static int bytesToInt(byte[] bytes) {   int addr = bytes[3] & 0xFF;   addr |= ((bytes[2] << 8) & 0xFF00);   addr |= ((bytes[1] << 16) & 0xFF0000);   addr |= ((bytes[0] << 24) & 0xFF000000);   return addr;  }  public static int ipToInt(String ipAddr) {   try {    return bytesToInt(ipToBytesByInet(ipAddr));   } catch (Exception e) {    throw new IllegalArgumentException(ipAddr + " is invalid IP");   }  }  public static byte[] intToBytes(int ipInt) {   byte[] ipAddr = new byte[INADDRSZ];   ipAddr[0] = (byte) ((ipInt >>> 24) & 0xFF);   ipAddr[1] = (byte) ((ipInt >>> 16) & 0xFF);   ipAddr[2] = (byte) ((ipInt >>> 8) & 0xFF);   ipAddr[3] = (byte) (ipInt & 0xFF);   return ipAddr;  }  public static String intToIp(int ipInt) {   return new StringBuilder().append(((ipInt >> 24) & 0xff)).append('.')     .append((ipInt >> 16) & 0xff).append('.').append(       (ipInt >> 8) & 0xff).append('.').append((ipInt & 0xff))     .toString();  }  public static int[] getIPIntScope(String ipAndMask) {   String[] ipArr = ipAndMask.split("/");   if (ipArr.length != 2) {    throw new IllegalArgumentException("invalid ipAndMask with: "      + ipAndMask);   }   int netMask = Integer.valueOf(ipArr[1].trim());   if (netMask < 0 || netMask > 31) {    throw new IllegalArgumentException("invalid ipAndMask with: "      + ipAndMask);   }   int ipInt = IPv4Util.ipToInt(ipArr[0]);   int netIP = ipInt & (0xFFFFFFFF << (32 - netMask));   int hostScope = (0xFFFFFFFF >>> netMask);   return new int[] { netIP, netIP + hostScope };  }  public static String[] getIPAddrScope(String ipAndMask) {   int[] ipIntArr = IPv4Util.getIPIntScope(ipAndMask);   return new String[] { IPv4Util.intToIp(ipIntArr[0]),     IPv4Util.intToIp(ipIntArr[0]) };  }  public static int[] getIPIntScope(String ipAddr, String mask) {   int ipInt;   int netMaskInt = 0, ipcount = 0;   try {    ipInt = IPv4Util.ipToInt(ipAddr);    if (null == mask || "".equals(mask)) {     return new int[] { ipInt, ipInt };    }    netMaskInt = IPv4Util.ipToInt(mask);    ipcount = IPv4Util.ipToInt("255.255.255.255") - netMaskInt;    int netIP = ipInt & netMaskInt;    int hostScope = netIP + ipcount;    return new int[] { netIP, hostScope };   } catch (Exception e) {    throw new IllegalArgumentException("invalid ip scope express ip:"      + ipAddr + " mask:" + mask);   }  }  public static String[] getIPStrScope(String ipAddr, String mask) {   int[] ipIntArr = IPv4Util.getIPIntScope(ipAddr, mask);   return new String[] { IPv4Util.intToIp(ipIntArr[0]),     IPv4Util.intToIp(ipIntArr[0]) };  }  public static void main(String[] args) throws Exception {   String ipAddr = "192.168.8.1";   byte[] bytearr = IPv4Util.ipToBytesByInet(ipAddr);   StringBuffer byteStr = new StringBuffer();   for (byte b : 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 = new StringBuffer();   for (byte b : 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));   int ipInt = IPv4Util.ipToInt(ipAddr);   System.out.println("IP: " + ipAddr + " --> int: " + ipInt);   System.out.println("int: " + ipInt + " --> IP: "     + IPv4Util.intToIp(ipInt));   String ipAndMask = "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]) + " ]");   String ipAddr1 = "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]) + " ]");  } }