非正则表达式判断是否是ipv6地址
package com.stackdump.ipv6.format;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
public class MainActivity extends Activity{
private final static int INADDR4SZ = 4;
private final static int INADDR16SZ = 16;
private final static int INT16SZ = 2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String ipStr = "2001:db8::1";
//判断是ipv6地址
if (isIPv6LiteralAddress(ipStr)) {
Log.d("stackdump","ipStr is ipv6");
}
}
public boolean isIPv6LiteralAddress(String src) {
return null != src && textToNumericFormatV6(src) != null;
}
public byte[] textToNumericFormatV6(String src) {
// Shortest valid string is "::", hence at least 2 chars
if (src.length() < 2) {
return null;
}
int colonp;
char ch;
boolean saw_xdigit;
int val;
char[] srcb = src.toCharArray();
byte[] dst = new byte[INADDR16SZ];
int srcb_length = srcb.length;
int pc = src.indexOf("%");
if (pc == srcb_length - 1) {
return null;
}
if (pc != -1) {
srcb_length = pc;
}
colonp = -1;
int i = 0, j = 0;
/* Leading :: requires some special handling. */
if (srcb[i] == ':')
if (srcb[++i] != ':')
return null;
int curtok = i;
saw_xdigit = false;
val = 0;
while (i < srcb_length) {
ch = srcb[i++];
int chval = Character.digit(ch, 16);
if (chval != -1) {
val <<= 4;
val |= chval;
if (val > 0xffff)
return null;
saw_xdigit = true;
continue;
}
if (ch == ':') {
curtok = i;
if (!saw_xdigit) {
if (colonp != -1)
return null;
colonp = j;
continue;
} else if (i == srcb_length) {
return null;
}
if (j + INT16SZ > INADDR16SZ)
return null;
dst[j++] = (byte) ((val >> 8) & 0xff);
dst[j++] = (byte) (val & 0xff);
saw_xdigit = false;
val = 0;
continue;
}
if (ch == '.' && ((j + INADDR4SZ) <= INADDR16SZ)) {
String ia4 = src.substring(curtok, srcb_length);
/* check this IPv4 address has 3 dots, ie. A.B.C.D */
int dot_count = 0, index = 0;
while ((index = ia4.indexOf('.', index)) != -1) {
dot_count++;
index++;
}
if (dot_count != 3) {
return null;
}
byte[] v4addr = textToNumericFormatV4(ia4);
if (v4addr == null) {
return null;
}
for (int k = 0; k < INADDR4SZ; k++) {
dst[j++] = v4addr[k];
}
saw_xdigit = false;
break; /* '\0' was seen by inet_pton4(). */
}
return null;
}
if (saw_xdigit) {
if (j + INT16SZ > INADDR16SZ)
return null;
dst[j++] = (byte) ((val >> 8) & 0xff);
dst[j++] = (byte) (val & 0xff);
}
if (colonp != -1) {
int n = j - colonp;
if (j == INADDR16SZ)
return null;
for (i = 1; i <= n; i++) {
dst[INADDR16SZ - i] = dst[colonp + n - i];
dst[colonp + n - i] = 0;
}
j = INADDR16SZ;
}
if (j != INADDR16SZ)
return null;
byte[] newdst = convertFromIPv4MappedAddress(dst);
if (newdst != null) {
return newdst;
} else {
return dst;
}
}
public byte[] convertFromIPv4MappedAddress(byte[] addr) {
if (isIPv4MappedAddress(addr)) {
byte[] newAddr = new byte[INADDR4SZ];
System.arraycopy(addr, 12, newAddr, 0, INADDR4SZ);
return newAddr;
}
return null;
}
public byte[] textToNumericFormatV4(String src) {
if (src.length() == 0) {
return null;
}
byte[] res = new byte[INADDR4SZ];
String[] s = src.split("\\.", -1);
long val;
try {
switch (s.length) {
case 1:
/*
* When only one part is given, the value is stored directly in
* the network address without any byte rearrangement.
*/
val = Long.parseLong(s[0]);
if (val < 0 || val > 0xffffffffL)
return null;
res[0] = (byte) ((val >> 24) & 0xff);
res[1] = (byte) (((val & 0xffffff) >> 16) & 0xff);
res[2] = (byte) (((val & 0xffff) >> 8) & 0xff);
res[3] = (byte) (val & 0xff);
break;
case 2:
/*
* When a two part address is supplied, the last part is
* interpreted as a 24-bit quantity and placed in the right
* most three bytes of the network address. This makes the
* two part address format convenient for specifying Class A
* network addresses as net.host.
*/
val = Integer.parseInt(s[0]);
if (val < 0 || val > 0xff)
return null;
res[0] = (byte) (val & 0xff);
val = Integer.parseInt(s[1]);
if (val < 0 || val > 0xffffff)
return null;
res[1] = (byte) ((val >> 16) & 0xff);
res[2] = (byte) (((val & 0xffff) >> 8) & 0xff);
res[3] = (byte) (val & 0xff);
break;
case 3:
/*
* When a three part address is specified, the last part is
* interpreted as a 16-bit quantity and placed in the right
* most two bytes of the network address. This makes the
* three part address format convenient for specifying
* Class B net- work addresses as 128.net.host.
*/
for (int i = 0; i < 2; i++) {
val = Integer.parseInt(s[i]);
if (val < 0 || val > 0xff)
return null;
res[i] = (byte) (val & 0xff);
}
val = Integer.parseInt(s[2]);
if (val < 0 || val > 0xffff)
return null;
res[2] = (byte) ((val >> 8) & 0xff);
res[3] = (byte) (val & 0xff);
break;
case 4:
/*
* When four parts are specified, each is interpreted as a
* byte of data and assigned, from left to right, to the
* four bytes of an IPv4 address.
*/
for (int i = 0; i < 4; i++) {
val = Integer.parseInt(s[i]);
if (val < 0 || val > 0xff)
return null;
res[i] = (byte) (val & 0xff);
}
break;
default:
return null;
}
} catch (NumberFormatException e) {
return null;
}
return res;
}
private boolean isIPv4MappedAddress(byte[] addr) {
if (addr.length < INADDR16SZ) {
return false;
}
if ((addr[0] == 0x00) && (addr[1] == 0x00) &&
(addr[2] == 0x00) && (addr[3] == 0x00) &&
(addr[4] == 0x00) && (addr[5] == 0x00) &&
(addr[6] == 0x00) && (addr[7] == 0x00) &&
(addr[8] == 0x00) && (addr[9] == 0x00) &&
(addr[10] == (byte) 0xff) &&
(addr[11] == (byte) 0xff)) {
return true;
}
return false;
}
}
若想了解ipv4地址格式的判断，可点击下方链接：https://stackdump.cn/java-%E5%AE%9E%E7%8E%B0ip%E5%9C%B0%E5%9D%80%E6%AD%A3%E5%88%99%E8%A1%A8%E8%BE%BE%E5%BC%8F/
0
《android 判断是否是ipv6地址》有1条留言
评论已关闭。