这是自己写的简单的解析pcap文件，方便读取pcap文件，大家参考使用吧

复制代码 代码如下:
InputStream is = DataParser.class.getClassLoader().getResourceAsStream("baidu_cdr.pcap");

Pcap pcap = PcapParser.unpack(is);
is.close();
byte[] t = pcap.getData().get(0).getContent();
byte[] data = Arrays.copyOfRange(t, 42, t.length);

PcapParser.java
复制代码 代码如下:
package com.hylanda.pcap;

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
* @author zhouqisheng
*
*/
public class PcapParser {

public static Pcap unpack(InputStream is) throws IOException {
Pcap pcap = null;
byte[] buffer_4 = new byte[4];
byte[] buffer_2 = new byte[2];
pcap = new Pcap();

PcapHeader header = new PcapHeader();
int m = is.read(buffer_4);
if(m != 4){
return null;
}
reverseByteArray(buffer_4);
header.setMagic(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_2);
reverseByteArray(buffer_2);
header.setMagor_version(byteArrayToShort(buffer_2, 0));
m = is.read(buffer_2);
reverseByteArray(buffer_2);
header.setMinor_version(byteArrayToShort(buffer_2, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
header.setTimezone(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
header.setSigflags(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
header.setSnaplen(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
header.setLinktype(byteArrayToInt(buffer_4, 0));

pcap.setHeader(header);

List<PcapData> dataList = new ArrayList<PcapData>();
while (m > 0) {
PcapData data = new PcapData();
m = is.read(buffer_4);
if (m < 0) {
break;
}
reverseByteArray(buffer_4);
data.setTime_s(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
data.setTime_ms(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
data.setpLength(byteArrayToInt(buffer_4, 0));
m = is.read(buffer_4);
reverseByteArray(buffer_4);
data.setLength(byteArrayToInt(buffer_4, 0));
byte[] content = new byte[data.getpLength()];
m = is.read(content);
data.setContent(content);

dataList.add(data);
}

pcap.setData(dataList);
return pcap;
}

private static int byteArrayToInt(byte[] b, int offset) {
int value = 0;
for (int i = 0; i < 4; i++) {
int shift = (4 - 1 - i) * 8;
value += (b[i + offset] & 0x000000FF) << shift;
}
return value;
}

private static short byteArrayToShort(byte[] b, int offset) {
short value = 0;
for (int i = 0; i < 2; i++) {
int shift = (2 - 1 - i) * 8;
value += (b[i + offset] & 0x000000FF) << shift;
}
return value;
}

/**
* 反转数组
* @param arr
*/
private static void reverseByteArray(byte[] arr){
byte temp;
int n = arr.length;
for(int i=0; i<n/2; i++){
temp = arr[i];
arr[i] = arr[n-1-i];
arr[n-1-i] = temp;
}
}

}

Pcap.java
复制代码 代码如下:
/**
*
*/
package com.hylanda.pcap;

import java.util.List;

/**
* @author zhouqisheng
*
*/
public class Pcap {
private PcapHeader header;
private List<PcapData> data;
public PcapHeader getHeader() {
return header;
}
public void setHeader(PcapHeader header) {
this.header = header;
}
public List<PcapData> getData() {
return data;
}
public void setData(List<PcapData> data) {
this.data = data;
}
@Override
public String toString(){
StringBuilder s = new StringBuilder();
s.append("header{\n");
s.append(header.toString());
s.append("}\n");
s.append("data part count=").append(data.size());

return s.toString();
}
}

PcapData.java
复制代码 代码如下:
package com.hylanda.pcap;

/**
* @author zhouqisheng
* 数据包头
*/
public class PcapData {
private int time_s;//时间戳（秒）
private int time_ms;//时间戳（微妙）
private int pLength;//抓包长度
private int length;//实际长度
private byte[] content;//数据
public int getTime_s() {
return time_s;
}
public void setTime_s(int time_s) {
this.time_s = time_s;
}
public int getTime_ms() {
return time_ms;
}
public void setTime_ms(int time_ms) {
this.time_ms = time_ms;
}
public int getpLength() {
return pLength;
}
public void setpLength(int pLength) {
this.pLength = pLength;
}
public int getLength() {
return length;
}
public void setLength(int length) {
this.length = length;
}
public byte[] getContent() {
return content;
}
public void setContent(byte[] content) {
this.content = content;
}

@Override
public String toString(){
StringBuilder s = new StringBuilder();
s.append("time_s=").append(this.time_s);
s.append("\ntime_ms=").append(this.time_ms);
s.append("\npLength=").append(this.pLength);
s.append("\nlength=").append(this.length);
return null;
}
}

PcapHeader.java
复制代码 代码如下:
package com.hylanda.pcap;

/**
* @author zhouqisheng
* pcap文件头
*/
public class PcapHeader {
private int magic;//文件识别头,为0xA1B2C3D4
private short magor_version;//主要版本
private short minor_version;//次要版本
private int timezone;//当地标准时间
private int sigflags;//时间戳的精度
private int snaplen;//最大的存储长度
/**
* 0 BSD loopback devices, except for later OpenBSD
1 Ethernet, and Linux loopback devices
6 802.5 Token Ring
7 ARCnet
8 SLIP
9 PPP
10 FDDI
100 LLC/SNAP-encapsulated ATM
101 “raw IP”, with no link
102 BSD/OS SLIP
103 BSD/OS PPP
104 Cisco HDLC
105 802.11
108 later OpenBSD loopback devices (with the AF_value in network byte order)
113 special Linux “cooked” capture
114 LocalTalk
*/
private int linktype;//链路类型
public int getMagic() {
return magic;
}
public void setMagic(int magic) {
this.magic = magic;
}
public short getMagor_version() {
return magor_version;
}
public void setMagor_version(short magor_version) {
this.magor_version = magor_version;
}
public short getMinor_version() {
return minor_version;
}
public void setMinor_version(short minor_version) {
this.minor_version = minor_version;
}
public int getTimezone() {
return timezone;
}
public void setTimezone(int timezone) {
this.timezone = timezone;
}
public int getSigflags() {
return sigflags;
}
public void setSigflags(int sigflags) {
this.sigflags = sigflags;
}
public int getSnaplen() {
return snaplen;
}
public void setSnaplen(int snaplen) {
this.snaplen = snaplen;
}
public int getLinktype() {
return linktype;
}
public void setLinktype(int linktype) {
this.linktype = linktype;
}

@Override
public String toString(){
StringBuilder s = new StringBuilder();
s.append("magic=").append("0x" + Integer.toHexString(this.magic));
s.append("\nmagor_version=").append(this.magor_version);
s.append("\nminor_version=").append(this.minor_version);
s.append("\ntimezone=").append(this.timezone);
s.append("\nsigflags=").append(this.sigflags);
s.append("\nsnaplen=").append(this.snaplen);
s.append("\nlinktype=").append(this.linktype);
return s.toString();
}
}