http断点续传简单实现（java)

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0 发表于: 2006-05-10

/*
**SiteFileFetch.java
*/
package NetFox;
import java.io.*;
import java.net.*;

public class SiteFileFetch extends Thread {

SiteInfoBean siteInfoBean = null; //文件信息Bean
long[] nStartPos; //开始位置
long[] nEndPos; //结束位置
FileSplitterFetch[] fileSplitterFetch; //子线程对象
long nFileLength; //文件长度
boolean bFirst = true; //是否第一次取文件
boolean bStop = false; //停止标志
File tmpFile; //文件下载的临时信息
DataOutputStream output; //输出到文件的输出流

//负责整个文件的抓取，控制内部线程（FileSplitterFetch类）
public SiteFileFetch(SiteInfoBean bean) throws IOException
{
siteInfoBean = bean;
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath()));
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info");
if(tmpFile.exists ())
{
bFirst = false;
read_nPos();
}
else
{
nStartPos = new long[bean.getNSplitter()];
nEndPos = new long[bean.getNSplitter()];
}

}

public void run()
{
//获得文件长度
//分割文件
//实例FileSplitterFetch
//启动FileSplitterFetch线程
//等待子线程返回
try{
if(bFirst)
{
nFileLength = getFileSize();
if(nFileLength == -1)
{
System.err.println("File Length is not known!");
}
else if(nFileLength == -2)
{
System.err.println("File is not access!");
}
else
{
for(int i=0;i<nStartPos.length;i++)
{
nStartPos = (long)(i*(nFileLength/nStartPos.length)); ][v]Nk
} )j>U4a
for(int i=0;i<nEndPos.length-1;i++) M\5|
{ o?hr>b
nEndPos = nStartPos[i+1]; UWvVYdy7
} >VkBQM-%
nEndPos[nEndPos.length-1] = nFileLength; qz>R"pj0g
} mA+:)?e5~
} ={zTQ+7S`
l9&k!kF`
, i5_4
//启动子线程 ebQgk Y=
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; jTcv&`fAz
for(int i=0;i<nStartPos.length;i++) n%7?G=_kj
{ qGV_oa74
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), y]fI7nu&
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ! I0xq"
nStartPos,nEndPos,i); ;: 2U}p^-
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ~! -JN}H m
fileSplitterFetch.start(); d/&> `[i
} lFyDH{!
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Oti*"dV\::
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); sE6>JaH
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", hDW!pnj1
nEndPos = " + nFileLength); nOGTeKjEJ
// fileSplitterFetch[nPos.length-1].start(); _y^r==
2H)4}5H
*(F`NJ 3
//等待子线程结束 EyE#x_A
//int count = 0; '|zrzU=
//是否结束while循环 rm,`M
boolean breakWhile = false; Yg^ &4ZF
E=p+z"Ui
sI!H=bp-8
while(!bStop) tbd=A]B-
{ ,|({[9jA
write_nPos(); k||t<&`Ze
Utility.sleep(500); 3S:Lce'f
breakWhile = true; h^yqrDyJ
9Ux(
VI&x1C
for(int i=0;i<nStartPos.length;i++) $Iwvecn?I
{ >%j%Mj@8q|
if(!fileSplitterFetch.bDownOver) 'rcqy1-&
{ -Z"4W
breakWhile = false; 147QB+cE
break; vjuFVJwL
} hJ}i+[~be
} z~ cW,
if(breakWhile) hzqJ!
break; j~Aq-8R=
w7V\_^&Id
i+*!"/De
//count++; :aesG7=O
//if(count>4) a#YK1n[!
// siteStop(); ]ordqulq1
} FlBhCZ|^
7zb^Z]
'a['lF
System.err.println("文件下载结束！"); fE-R(9K
} P8tdT3*6/
catch(Exception e){e.printStackTrace ();} H3A$YkK [
} 513,k$7
r )F;8(
$9)os7H7
//获得文件长度 i+Z)`
public long getFileSize() ~]?:v,UIm(
{ va6Fp2n<1*
int nFileLength = -1; EuK}L[Kl
try{ u"[f\l
URL url = new URL(siteInfoBean.getSSiteURL()); _fHC+lwN
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); &9L4 t%As
httpConnection.setRequestProperty("User-Agent","NetFox"); s2;~FK#/
Bm$|XS3cD
v"USD<
int responseCode=httpConnection.getResponseCode(); xE/?ncTK^
if(responseCode>=400) t#k]K]
{ m=dNJF
processErrorCode(responseCode); cHjQwl
return -2; //-2 represent access is error hyI7X7Hy
} GWA"!~Hu
(jT)o,IW&
?Nos;_/
String sHeader; #-/W?kD
2Ez<Iw
;J%:DD
for(int i=1;;i++) xye-Z\-t
{ PTQ#8(_,
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); HK;NR.D
//Utility.log(in.readLine()); DB'v7 Ij0
sHeader=httpConnection.getHeaderFieldKey(i); sPH2KwEv
if(sHeader!=null) VoU8I ~
{ 66yw[,Y
if(sHeader.equals("Content-Length")) nV'1 $L#
{ zF1!a
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); -`O{iHfM|P
break; %w`d
} ~tDYo)hH8
} u`pTFy
else rB>ge]$.
break; &>sbsx\y
} @X==[gQ
} 2HX/@ERhmu
catch(IOException e){e.printStackTrace ();} (MwRe?Ih
catch(Exception e){e.printStackTrace ();} YpZB-9Krf
ACszx\[K3
J'44j;5&
Utility.log(nFileLength); }vndt*F
':*H#}Br-#
d"wA"*8~y
return nFileLength; I/E9:
} |[\;.gT K
[+ud7l
'&IGdB I
//保存下载信息（文件指针位置） EVmBLH-a
private void write_nPos() eqx }]#
{ bo0U
try{ ;mQj2Bwr
output = new DataOutputStream(new FileOutputStream(tmpFile)); _CwTe=K}
output.writeInt(nStartPos.length); X8C7d6ca
for(int i=0;i<nStartPos.length;i++) 7;>|9k
{ HDe\Oty_
// output.writeLong(nPos); i|:!I)(lh
output.writeLong(fileSplitterFetch.nStartPos); epy2}TI
output.writeLong(fileSplitterFetch.nEndPos); 9+ 'i(q z
} ,H=k5WA4m
output.close(); dCC*|b8h
} v$ ti=uk$
catch(IOException e){e.printStackTrace ();} dN8Mfa)
catch(Exception e){e.printStackTrace ();} %>KbaM1b
} E7Lqa S
pH'_k k
fO<40!%9cQ
//读取保存的下载信息（文件指针位置） Tzq@ic#!B
private void read_nPos() nrac)W
{ WzIUHNn'I
try{ wZvv5:jKpu
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 0 QTI;3
int nCount = input.readInt(); mU5Ox4>&9
nStartPos = new long[nCount]; gInh+XZs
nEndPos = new long[nCount]; O8]e(i
for(int i=0;i<nStartPos.length;i++) 0Lo8pe`DH
{ BJ|l
nStartPos = input.readLong(); &@iOB #H
nEndPos = input.readLong(); zxR]+9Zh
} kwjO5OC8
input.close(); sz9W}&(j
} !M^O\C)
catch(IOException e){e.printStackTrace ();} VLuHuih
catch(Exception e){e.printStackTrace ();} <)7aNW.
} (&}[2pb!
o/pw=R/):
Pn,I^Ej.
private void processErrorCode(int nErrorCode) wQ33Gc
{ VN`.*B|9[
System.err.println("Error Code : " + nErrorCode); $1yy;IyR
} IkCuw./
I~4z%UG
,Lig6Z`
//停止文件下载 wJC[[_"3 I
public void siteStop() L FWp}#%
{ M7=,J;@
bStop = true; VZ9 p "
for(int i=0;i<nStartPos.length;i++) u)@:V)z
fileSplitterFetch.splitterStop(); q?!HzZ
$nt&'Xnv
g+#<;Gbpe
} SBxpJsW>
} xfRp_;l+R
//负责部分文件的抓取 Pe<VPf9+
**FileSplitterFetch.java Ci`o;KVj
*/ Ark]>4x>
package NetFox; &%2^B[{
|=0vgwd"S
yCQvo(V[F
import java.io.*; Yq ]sPE92
import java.net.*; m.D8@[y
5*44QV
MG?,,8sO
public class FileSplitterFetch extends Thread { 5zK,(cF0-
d6n_Hpxw^
TAG@Ab
String sURL; //File URL G_+/ e]P
long nStartPos; //File Snippet Start Position ~Dt$}l-9
long nEndPos; //File Snippet End Position SH)-(+72d
int nThreadID; //Thread's ID "z9C@T
boolean bDownOver = false; //Downing is over Sr \y1nt
boolean bStop = false; //Stop identical 2"D4q(@
FileAccessI fileAccessI = null; //File Access interface \ ca<L
8UU L=
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException g+B7~Z5,
{ F0!Z1S0g
this.sURL = sURL; (_ G>dP_
this.nStartPos = nStart; sU>IETo
this.nEndPos = nEnd; ,sitOy}ks
nThreadID = id; ~cc }yDe
fileAccessI = new FileAccessI(sName,nStartPos);//定位 r;{$x
} LG8h@HY&L
-=5~h
26p[x'W
public void run() LK DfV
{ fg LY{
while(nStartPos < nEndPos && !bStop) ^]sb=Amw
{ :\[l~S
sJZ2e6?n
b? o
try{ \ ku5%y
URL url = new URL(sURL); GQYR`;>
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); SMrfEmdH+
httpConnection.setRequestProperty("User-Agent","NetFox"); e*Wk;D&
String sProperty = "bytes="+nStartPos+"-"; V;eaQ
httpConnection.setRequestProperty("RANGE",sProperty); Lf(( zk:pt
Utility.log(sProperty); ulxlh8=
hEHd$tH06
t+a.,$U
InputStream input = httpConnection.getInputStream(); HQ@g6
//logResponseHead(httpConnection); ^2- <XD)
m%6VwV7U
bkd`7(r
byte[] b = new byte[1024]; 5QiQDQT}5
int nRead; JaUzu3*=
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) |RL#BKC`
{ wW\[#Ku
nStartPos += fileAccessI.write(b,0,nRead); S46aUkW.
//if(nThreadID == 1) 2{?]W/&fS
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Dizz?O
} 42]7N3:'
<7]HM5h
}`gOfj)?i
Utility.log("Thread " + nThreadID + " is over!"); rnZ$Qk-H
bDownOver = true; lQ?jdi
//nPos = fileAccessI.write (b,0,nRead); =sk[I0W
} N`Q.u-'
catch(Exception e){e.printStackTrace ();} nsI+04[F
} :V.@:x>id
} Ms|c"?se
9" q-Bb
],SQD3~9
//打印回应的头信息 f(pq`v^-n
public void logResponseHead(HttpURLConnection con) #VrIU8Q7'
{ B,\VLX
for(int i=1;;i++) s21} a,eB
{ xuvW6Q;
String header=con.getHeaderFieldKey(i); UiG/Rn
if(header!=null) 5Rl\& G\
//responseHeaders.put(header,httpConnection.getHeaderField(header)); gbuh04#~
Utility.log(header+" : "+con.getHeaderField(header)); J>
else Ef#LRcG-Z
break; tQ{/9bN?P
} nmU1xv_
} ZHK>0>;
."+lij=56
0:v!'
public void splitterStop() wS}c\!@<,
{ :$"{-n
bStop = true; W q<t+E[
} Iuxf`sd
-!XG>Z
8Nzn%0(Q
} V8/d27\
ZoXz@/T
(S!UnBb&
/* b11I$b #
**FileAccess.java 4<-Kd~uL
*//文件访问(定位，写) Em(_W5 ND{
package NetFox; M)ET1ZM
import java.io.*; W p)!G
'u<e<hU
<'4Wne.z!
public class FileAccessI implements Serializable{ K(?V]Mxl6
c6[m'cy
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 0ZjT.Ep
RandomAccessFile oSavedFile; ]W?cy
long nPos; %<>:$4U@]
t+KW=eW
futYMoV
public FileAccessI() throws IOException ^# $IoW
{ Z)|~
this("",0); \s#~ %l
} 3?B1oIHQ
B[ZQn]y
nDvfb*\
public FileAccessI(String sName,long nPos) throws IOException rpiuFst
{ w<B S
oSavedFile = new RandomAccessFile(sName,"rw"); Xgx/ubca0
this.nPos = nPos; |6Y:W$7k
oSavedFile.seek(nPos); iOZ9A~Ywy
} @S3L%lOH
_9=87u0
<ci(5M
public synchronized int write(byte[] b,int nStart,int nLen) bR7tmJ[)Z
{ JAHg_!
int n = -1; $?F_Qsy{d
try{ RP2$(%
oSavedFile.write(b,nStart,nLen); Lz1KDXr`)+
n = nLen; h~Ir=JV
} <zqIq9}r
catch(IOException e) "S#$:92
{ \Yj_U'2"i
e.printStackTrace (); )$p36dWl
} Vl$RMW@Ds
BW;@Gq@N
N|mggz
return n; eY`z\I
} 9%kO%j,3
pzRVX8
Uhvy2}w
} Pm P&Qje7
(;g/wb:
hD#Mhy5h
/* {KSLB8gtL
**SiteInfoBean.java 6DHZ,gWq
*/ <,O|fY%
package NetFox; bo/U5p
BT(eU*m-
j7);N
public class SiteInfoBean { GF@`~im
:{eYm|2-
[GCaRk>b,
private String sSiteURL; //Site's URL L|{vkkBo
private String sFilePath; //Saved File's Path }cUO+)!Y
private String sFileName; //Saved File's Name w:I!{iX
private int nSplitter; //Count of Splited Downloading File <b~~X`Z
KKk<wya&O
2 .Xx)(>
public SiteInfoBean() PQi(Oc
{//nSplitter的缺省值为5 Z[!kEW
//default value of nSplitter is 5 n2o)K;wW+
this("","","",5); ;<o?JM
} c;KMox/
2I suBX\[
9h+TO_T@F
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 'o=DGm2H
{ 1.,KN:qe
sSiteURL= sURL; ;fQIaE&H
sFilePath = sPath; 6e|uA7i4
sFileName = sName; 5l,Lp'k
this.nSplitter = nSpiltter; |BtFT
o]]tH
\ %xku:
} 25 U+L
T#e|{ZCbq
$BLd>gTzmv
public String getSSiteURL() giIPK&
{ @}r s6 G
return sSiteURL; $Ups9pQ
} CG35\b;Q
/A>nsN?:]
r0OP !u
public void setSSiteURL(String value) .f[z_%ar
{ 6h) &h1Yd
sSiteURL = value; 1JOoICjB
} JS?%zj&@
%LqT>HXJ
U.Z5;E0:
public String getSFilePath() ;B }4pv}
{ ?{L'd
return sFilePath; ww+,GnV
} Q7zpu/5?
d|gfp:Z`a
@d0~'_vtB
public void setSFilePath(String value) W8-vF++R
{ X-CoC
sFilePath = value; 4qd(a)NdY
} UsCaO<A
(6 RWI#
?oV|.LM:W
public String getSFileName() Y!ypG-
{ 4,=;:#n,J
return sFileName; ]Ee$ulJ02
} s I0:<6W
M`* BS
~?iQnQYI
public void setSFileName(String value) [CAFh:o
{ _Db&f}.`
sFileName = value; zW`a]n.
} YKOj
{=,I>w]T|W
.jbxA2
public int getNSplitter() alsD TQ'
{ <<Z, 1{3F
return nSplitter; \lwLVe
} 7e#|Iq:o
e)XnS'
}{&;\^i
public void setNSplitter(int nCount) {lppv(U
{ >4+KEK
nSplitter = nCount; r{*BJi.b
} Y%}N@ ,lT
} H%}/O;C
Qte%<POx+
s5*HS3D
/* _lm^v%J$
**Utility.java wAL}c(EHO
*/ p|BoEITL
package NetFox; {&6i$4T
T)ISDK4>S"
h 'Hnq m
public class Utility { F'B0\v=
Y; to9Kv$
dB:c2
public Utility() uW!saT5o
{ B`jq"[w]-
2n-kJl`: O
Qam48XZ >
} &rl;+QS
$3%+N|L
//线程睡眠 +F2X2e)g"
public static void sleep(int nSecond) 'P[#.9E
{ $2-_j)+
try{ o)R<sT
Thread.sleep(nSecond); H/={RuU
} h@y>QhYU0
catch(Exception e) qOnGP{
{ 3=*ur( Qy
e.printStackTrace (); wkV'']= Xg
} Ki&a"Fu3
} 9QL%q; #
DQaE9gmC
//日志 =);@<Jp
public static void log(String sMsg) GQQp(%T
{ A r>BL2@
System.err.println(sMsg); "^;h'
} ]]3rSXs2}J
~P;A 9A(k
x;Slv(|M
public static void log(int sMsg) ,|.}6\zl*{
{ pVrY';[,|
System.err.println(sMsg); vAqj4:j
} qPN9Put
} PL3hrI 5
D!.1R!(Z
=Vazxt@[
/* VxARJ*4=Y
**TestMethod.java F[`dX
*/ J_m@YkK
package NetFox; GG +T-
-5ZmIlL.S
CjP<'0gT
public class TestMethod { $bFK2yx?=
o0|Ex\
Im@OAR4,R
public TestMethod() 7')W+`o8eL
{ ///xx/weblogic60b2_win.exe <JU3sXl
try{ =WBfaxL}
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); |D%mWQng
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); u*rP8GuS
SiteFileFetch fileFetch = new SiteFileFetch(bean); & d2`{H
fileFetch.start(); 4KnBb_w
} x&0kIF'lq
catch(Exception e){e.printStackTrace ();} OE9,D:tv
n-yUt72
s.Ai_D
} 3}F>t{FDk
$?bD55
]+W){W=ai
public static void main(String[] args) ^879sI
{ %Uz\P|6PO
new TestMethod(); f:<BUqa
} gu[EYg
} j-W$)c3X
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