OS DNS缓存
>ipconfig /displaydns
Windows IP Configuration
hm.e.shifen.com
----------------------------------------
Record Name . . . . . : hm.e.shifen.com
Record Type . . . . . : 1
Time To Live . . . . : 105
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 111.206.209.249
hm.e.shifen.com
----------------------------------------
Record Name . . . . . : hm.e.shifen.com
Record Type . . . . . : 28
Time To Live . . . . : 152
Data Length . . . . . : 16
Section . . . . . . . : Answer
AAAA Record . . . . . : 2408:80f0:410b:2ae:0:ff:b089:569d
kunpeng.csdn.net
----------------------------------------
Record Name . . . . . : kunpeng.csdn.net
Record Type . . . . . : 1
Time To Live . . . . : 144
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 101.201.173.208
hub5pr.sandai.net
----------------------------------------
Record Name . . . . . : hub5pr.sandai.net
Record Type . . . . . : 1
Time To Live . . . . : 603169
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 121.9.209.134
stats.l.doubleclick.net
----------------------------------------
Record Name . . . . . : stats.l.doubleclick.net
Record Type . . . . . : 1
Time To Live . . . . : 47
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 114.250.65.38
zhannei-dm.csdn.net
----------------------------------------
Record Name . . . . . : zhannei-dm.csdn.net
Record Type . . . . . : 1
Time To Live . . . . : 130
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 101.201.173.208
www-google-analytics.l.google.com
----------------------------------------
Record Name . . . . . : www-google-analytics.l.google.com
Record Type . . . . . : 1
Time To Live . . . . : 12
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 114.250.66.33
www.google-analytics.com
----------------------------------------
Record Name . . . . . : www.google-analytics.com
Record Type . . . . . : 5
Time To Live . . . . : 10722
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : www-google-analytics.l.google.com
www.google-analytics.com
----------------------------------------
Record Name . . . . . : www.google-analytics.com
Record Type . . . . . : 5
Time To Live . . . . : 10722
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : www-google-analytics.l.google.com
test.com
----------------------------------------
Record Name . . . . . : test.com
Record Type . . . . . : 1
Time To Live . . . . : 603169
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 192.168.0.109
dl2.iteye.com
----------------------------------------
Record Name . . . . . : dl2.iteye.com
Record Type . . . . . : 5
Time To Live . . . . : 7
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : dl2-iteye-com-idvfzoo.qiniudns.com
dl2.iteye.com
----------------------------------------
Record Name . . . . . : dl2.iteye.com
Record Type . . . . . : 5
Time To Live . . . . : 7
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : dl2-iteye-com-idvfzoo.qiniudns.com
dl2.iteye.com
----------------------------------------
Record Name . . . . . : dl2.iteye.com
Record Type . . . . . : 5
Time To Live . . . . : 7
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : dl2-iteye-com-idvfzoo.qiniudns.com
kunyu.csdn.net
----------------------------------------
Record Name . . . . . : kunyu.csdn.net
Record Type . . . . . : 1
Time To Live . . . . : 129
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 47.95.182.167
qd-update.qq.com
----------------------------------------
Record Name . . . . . : qd-update.qq.com
Record Type . . . . . : 1
Time To Live . . . . : 2089
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 58.251.112.242
Record Name . . . . . : qd-update.qq.com
Record Type . . . . . : 1
Time To Live . . . . : 2089
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 58.251.112.89
Record Name . . . . . : qd-update.qq.com
Record Type . . . . . : 1
Time To Live . . . . : 2089
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 58.250.11.124
Record Name . . . . . : qd-update.qq.com
Record Type . . . . . : 1
Time To Live . . . . : 2089
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 113.96.12.221
lobin.iteye.com
----------------------------------------
Record Name . . . . . : lobin.iteye.com
Record Type . . . . . : 1
Time To Live . . . . : 2
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 101.201.174.210
beacon.tingyun.com
----------------------------------------
Record Name . . . . . : beacon.tingyun.com
Record Type . . . . . : 1
Time To Live . . . . : 18
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 140.143.52.226
Record Name . . . . . : beacon.tingyun.com
Record Type . . . . . : 1
Time To Live . . . . : 18
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 140.143.49.61
zz.bdstatic.com
----------------------------------------
Record Name . . . . . : zz.bdstatic.com
Record Type . . . . . : 5
Time To Live . . . . : 1209
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : sslzz.jomodns.com
zz.bdstatic.com
----------------------------------------
Record Name . . . . . : zz.bdstatic.com
Record Type . . . . . : 5
Time To Live . . . . : 1209
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : sslzz.jomodns.com
safebrowsing.google.com
----------------------------------------
Record Name . . . . . : safebrowsing.google.com
Record Type . . . . . : 5
Time To Live . . . . : 9944
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . : sb.l.google.com
safebrowsing.google.com
----------------------------------------
Record Name . . . . . : safebrowsing.google.com
Record Type . . . . . : 5
Time To Live . . . . : 9944
Data Length . . . . . : 4
Section . . . . . . . : Answer
Chrome DNS缓存
访问chrome://net-internals/#dns
也可以访问chrome://net-internals，然后选择“DNS”
报文头
typedef struct {
unsigned id :16; // query identification number
#if BYTE_ORDER == BIG_ENDIAN
// fields in third byte
unsigned qr: 1; // response flag
unsigned opcode: 4; // purpose of message
unsigned aa: 1; // authoritive answer
unsigned tc: 1; // truncated message
unsigned rd: 1; // recursion desired
// fields in fourth byte
unsigned ra: 1; // recursion available
unsigned unused :3; // unused bits (MBZ as of 4.9.3a3)
unsigned rcode :4; // response code
#endif
#if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
// fields in third byte
unsigned rd :1; // recursion desired
unsigned tc :1; // truncated message
unsigned aa :1; // authoritive answer
unsigned opcode :4; // purpose of message
unsigned qr :1; // response flag
// fields in fourth byte
unsigned rcode :4; // response code
unsigned unused :3; // unused bits (MBZ as of 4.9.3a3)
unsigned ra :1; // recursion available
#endif
// remaining bytes
unsigned qdcount :16; // number of question entries
unsigned ancount :16; // number of answer entries
unsigned nscount :16; // number of authority entries
unsigned arcount :16; // number of resource entries
} HEADER;
响应报文解析
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.SocketChannel;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
public class SocketChannelInput extends AbstractInput {
private SocketChannel channel;
public SocketChannelInput(SocketChannel channel) {
this.channel = channel;
}
private ByteBuffer readBuffer(int bytes) throws IOException {
ByteBuffer dst = ByteBuffer.allocate(bytes);
while (dst.hasRemaining()) {
channel.read(dst);
}
dst.rewind();
return dst;
}
private int readLength() throws IOException {
ByteBuffer dst = readBuffer(2);
return dst.getShort();
}
private ByteBuffer readMessage(int length) throws IOException {
return readBuffer(length);
}
/**
* question section
*/
private void readSection2(ByteBuffer src, int n) {
for (int i = 0; i < n; i++) {
StringBuffer qname = new StringBuffer();
int ll = 0;
while ((ll = src.get()) != 0) {
qname.append(ll);
for (int j = 0; j < ll; j++) {
qname.append((char) src.get());
}
}
qname.append(0);
int qtype = src.getShort();
int qclass = src.getShort();
Entry entry = new Entry(qname.toString(), (short) qtype, (short) qclass);
System.out.println(ToStringBuilder.reflectionToString(entry, ToStringStyle.MULTI_LINE_STYLE));
}
}
/**
* resource record
*/
private void readRecord(ByteBuffer src) {
String name = null;
int prefix = src.getShort();
int flag = (prefix << 16) >>> 30;
if (flag == 3) {
int offset = (prefix << 18) >>> 18;
int position = src.position();
src.position(offset);
StringBuffer sb = new StringBuffer();
int ll = 0;
while ((ll = src.get()) != 0) {
sb.append(ll);
for (int j = 0; j < ll; j++) {
sb.append((char) src.get());
}
}
sb.append(0);
name = sb.toString();
src.position(position);
} else {
}
System.out.println(name);
int type = src.getShort();
System.out.println(type);
int clazz = src.getShort();
System.out.println(clazz);
int ttl = src.getInt();
System.out.println(ttl);
int length = src.getShort();
System.out.println(length);
StringBuffer data = new StringBuffer();
ByteBuffer db = readRecordData(src, length);
int position = db.position();
prefix = db.getShort();
db.position(position);
flag = (prefix << 16) >>> 30;
if (flag == 3) {
int offset = (prefix << 18) >>> 18;
position = src.position();
src.position(offset);
int ll = 0;
while ((ll = src.get()) != 0) {
data.append(ll);
for (int j = 0; j < ll; j++) {
data.append((char) src.get());
}
}
data.append(0);
src.position(position);
}
// position = db.position();
int suffix = db.getShort(db.limit() - 2);
int term = db.get(db.limit() - 2);
// db.position(position);
flag = (suffix << 16) >>> 30;
if (flag == 3) {
int ll = 0;
while ((ll = db.get()) != term) {
data.append(ll);
for (int j = 0; j < ll; j++) {
data.append((char) db.get());
}
}
int offset = (suffix << 18) >>> 18;
position = src.position();
src.position(offset);
ll = 0;
while ((ll = src.get()) != 0) {
data.append(ll);
for (int j = 0; j < ll; j++) {
data.append((char) src.get());
}
}
data.append(0);
src.position(position);
}
flag = db.get(db.limit() - 1);
if (flag == 0) {
int ll = 0;
while ((ll = db.get()) != 0) {
data.append(ll);
for (int j = 0; j < ll; j++) {
data.append((char) db.get());
}
}
data.append(0);
}
System.out.println(data);
}
/**
* answer, authority, additional section
*/
private void readSection(ByteBuffer src, int n) {
for (int i = 0; i < n; i++) {
readRecord(src);
}
}
/**
* answer section
*/
private void readSection3(ByteBuffer src, int n) {
readSection(src, n);
}
/**
* authority section
*/
private void readSection4(ByteBuffer src, int n) {
readSection(src, n);
}
/**
* additional section
*/
private void readSection5(ByteBuffer src, int n) {
readSection(src, n);
}
public void reply() throws IOException {
// 0, 12, 0, 17, -128, 1, 0, 0, 0, 0, 0, 0, 0, 0
// 2, 8, 0, 17, -127, 0, 0, 1, 0, 0, 0, 13, 0, 15, 3, 119, 119, 119, 6, 104, 97, 111, 49, 50, 51, 3, 99, 111, 109, 0, 0, 1, 0, 1, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 20, 1, 104, 12, 103, 116, 108, 100, 45, 115, 101, 114, 118, 101, 114, 115, 3, 110, 101, 116, 0, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 99, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 101, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 98, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 109, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 97, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 103, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 108, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 105, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 102, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 100, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 107, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 106, -64, 46, -64, -116, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 5, 6, 30, -64, 108, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 33, 14, 30, -64, 76, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 26, 92, 30, -64, -36, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 31, 80, 30, -64, 92, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 12, 94, 30, -64, -52, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 35, 51, 30, -64, -100, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 42, 93, 30, -64, 44, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 54, 112, 30, -64, -68, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 43, -84, 30, -64, -4, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 48, 79, 30, -64, -20, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 52, -78, 30, -64, -84, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 41, -94, 30, -64, 124, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 55, 83, 30, -64, -116, 0, 28, 0, 1, 0, 2, -93, 0, 0, 16, 32, 1, 5, 3, -88, 62, 0, 0, 0, 0, 0, 0, 0, 2, 0, 48, -64, 108, 0, 28, 0, 1, 0, 2, -93, 0, 0, 16, 32, 1, 5, 3, 35, 29, 0, 0, 0, 0, 0, 0, 0, 2, 0, 48, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
// 2, 8, 0, 17, -128, 0, 0, 1, 0, 0, 0, 13, 0, 15, 3, 119, 119, 119, 6, 104, 97, 111, 49, 50, 51, 3, 99, 111, 109, 0, 0, 1, 0, 1, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 20, 1, 99, 12, 103, 116, 108, 100, 45, 115, 101, 114, 118, 101, 114, 115, 3, 110, 101, 116, 0, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 108, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 100, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 107, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 103, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 104, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 97, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 109, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 106, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 98, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 101, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 102, -64, 46, -64, 23, 0, 2, 0, 1, 0, 2, -93, 0, 0, 4, 1, 105, -64, 46, -64, -100, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 5, 6, 30, -64, -52, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 33, 14, 30, -64, 44, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 26, 92, 30, -64, 92, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 31, 80, 30, -64, -36, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 12, 94, 30, -64, -20, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 35, 51, 30, -64, 124, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 42, 93, 30, -64, -116, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 54, 112, 30, -64, -4, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 43, -84, 30, -64, -68, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 48, 79, 30, -64, 108, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 52, -78, 30, -64, 76, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 41, -94, 30, -64, -84, 0, 1, 0, 1, 0, 2, -93, 0, 0, 4, -64, 55, 83, 30, -64, -100, 0, 28, 0, 1, 0, 2, -93, 0, 0, 16, 32, 1, 5, 3, -88, 62, 0, 0, 0, 0, 0, 0, 0, 2, 0, 48, -64, -52, 0, 28, 0, 1, 0, 2, -93, 0, 0, 16, 32, 1, 5, 3, 35, 29, 0, 0, 0, 0, 0, 0, 0, 2, 0, 48, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
int length = readLength();
ByteBuffer bb = readMessage(length);
int id = bb.getShort();
int b = bb.get();
int qr = b >> 7;
boolean query = qr == 0 ? true : false;
int opcode = (b << 25) >> 28;
int aa = (b << 29) >> 31;
int tc = (b << 30) >> 31;
int rd = (b << 31) >> 31;
b = bb.get();
int ra = b >> 7;
int rcode = b & 0x0F;
// number of entries in the question section
int n2 = bb.getShort();
System.out.println(n2);
// number of resource records in the answer section
int n3 = bb.getShort();
System.out.println(n3);
// number of name server resource records in the authority
// records section
int n4 = bb.getShort();
System.out.println(n4);
int n5 = bb.getShort();
System.out.println(n5);
readSection2(bb, n2);
readSection3(bb, n3);
readSection4(bb, n4);
readSection5(bb, n5);
}
private ByteBuffer readRecordData(ByteBuffer src, int length) {
ByteBuffer dst = ByteBuffer.allocate(length);
while (dst.hasRemaining()) {
dst.put(src.get());
}
dst.rewind();
return dst;
}
}
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