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)); &hOz(825r
} -%asHDQ{
for(int i=0;i<nEndPos.length-1;i++) p* >z:=
{ }3(!kW
nEndPos = nStartPos[i+1]; )Qbd/zd\U
} XqTguO'
nEndPos[nEndPos.length-1] = nFileLength; G/_IY;
} z(|^fi(
} 5ya9VZ5#
fkV@3sj
iGyetFqKw
//启动子线程 \@<7Vo,
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; }9fa]D-a?
for(int i=0;i<nStartPos.length;i++) /_C2O"h
{ ?.~1%l!
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), &\h7E
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 98[uRywI
nStartPos,nEndPos,i); B~Sj#(WEa
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); &LLU@|
fileSplitterFetch.start(); &uq.k{<p\
} &K^0PzWWof
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), UC!mp?
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); tB_le>rhl
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", ai!u+L
nEndPos = " + nFileLength); v3-/ [-XB:
// fileSplitterFetch[nPos.length-1].start(); /$~1e7W
RN$vKJk
TGCB=e
//等待子线程结束 f{sT*_at
//int count = 0; j}+3+ 8D
//是否结束while循环 vm [lMx
boolean breakWhile = false; E7Cobpm
8U{D)KgS
5zl+M`
while(!bStop) ;4F6 $T'I
{ R/hf"E1
write_nPos(); r4yz{^G
Utility.sleep(500); E]V, @
breakWhile = true; (,|,j(=]
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;:;E|{e
for(int i=0;i<nStartPos.length;i++) UK=ELvt]
{ ,.,8-In^
if(!fileSplitterFetch.bDownOver) P>/:dt'GJ}
{ o@meogkL
breakWhile = false; }d[(kC_
break; ^FVdA1~/
} +f3Rzx]
} opcanl9pSW
if(breakWhile) Hm-#Mpw
break; YI0 wr1N
`+H=3`}X
A7p4M?09
//count++; jv)+qmqo!
//if(count>4) bvox7V>
// siteStop(); "HOZ2_(o
} ~1G^IZ6
ptCF))Zm'
\:vF FK4a
System.err.println("文件下载结束！"); WogUILB
} c{q+h V=
catch(Exception e){e.printStackTrace ();} }Fe~XO`
} BQu |qrq
8_Oeui(i
"j>X^vn
//获得文件长度 {R1]tGOf
public long getFileSize() rOJ>lPs
{ Y=S0|!u
int nFileLength = -1; 5KCQvv\
try{ #xIg(nG
URL url = new URL(siteInfoBean.getSSiteURL()); yD9enYM
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Liqo)m
httpConnection.setRequestProperty("User-Agent","NetFox"); bt}8ymcG
{##G.n\~
v?8WQNy
int responseCode=httpConnection.getResponseCode(); Ob0sB@
if(responseCode>=400) {oQs*`=l>
{ @|gG3
processErrorCode(responseCode); 15:9JVH3D
return -2; //-2 represent access is error !0{SVsc)
} ]kj^T?&n.
{*xE+ |
4^7 v@3
String sHeader; o}N@Q-i gq
LU3pCM{
h&"9v~
for(int i=1;;i++) V)$!WPL@
{ C5~#lNC
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); a&s34Pd
//Utility.log(in.readLine()); kWzp*<lWe
sHeader=httpConnection.getHeaderFieldKey(i); ~ 'ZwD/!e
if(sHeader!=null) dSDZMB sd
{ u8f\)m
if(sHeader.equals("Content-Length")) \0\O/^W0
{ O&Y;/$w
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); %ZVYgtk;*
break; WjVBz
} JVAyiNIH>M
} :H}iL*
else (KQLh,h7
break; bT:u|/I
} 5`h 6oFxGp
} @c~Z0+Ji
catch(IOException e){e.printStackTrace ();} >X~B1D,SV7
catch(Exception e){e.printStackTrace ();} *yZ6"
Ww<Y]H$xZ<
Ah2@sp,z
Utility.log(nFileLength); a%#UF@I
Tm%5:/<8
-`]9o3E7H
return nFileLength; kowS| c#
} a;o0#I#Si
)%C.IZ_s2
4$-R|@,|_
//保存下载信息（文件指针位置） I;4quFBlMu
private void write_nPos() gawY{Jr8I
{ !j!w$
try{ Y9.3`VX
output = new DataOutputStream(new FileOutputStream(tmpFile)); -}7$;QK&a
output.writeInt(nStartPos.length); dL42)HP5
for(int i=0;i<nStartPos.length;i++) {"o9pIh{~
{ *@rA7zPFf
// output.writeLong(nPos); ]d*9@+Iu
output.writeLong(fileSplitterFetch.nStartPos); oW~W(h!
output.writeLong(fileSplitterFetch.nEndPos); Zkp~qx
} F^l1WX6
output.close(); yi$CkG}
} &xGdKH
catch(IOException e){e.printStackTrace ();} {B$CqsvJ
catch(Exception e){e.printStackTrace ();} 80nEQT y
} 7L~*%j
& SXw=;B
Z`TfS+O6
//读取保存的下载信息（文件指针位置） 1/$PxQ
private void read_nPos() O-, "/Z
{ * + T(i
try{ ! ._q8q\
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); &}DfIP<
int nCount = input.readInt(); y##h(y
nStartPos = new long[nCount]; .}__XWK5
nEndPos = new long[nCount]; CW1l;uwtU
for(int i=0;i<nStartPos.length;i++) 9p_?t'&>q
{ @a8lF$<
nStartPos = input.readLong(); Tm"H9
nEndPos = input.readLong(); oidZWy
} Jm_)}dj3o
input.close(); '_v~+
} V%-hP~nyBx
catch(IOException e){e.printStackTrace ();} qda 2
catch(Exception e){e.printStackTrace ();} ebA:Sq:w
} dIC\U
0)&!$@HW
x%dny]O1;
private void processErrorCode(int nErrorCode) VMah3T!
{ GvVkb=="
System.err.println("Error Code : " + nErrorCode); 7}iv+rQ
} J;& y?%{@5
::Zo` vP
/WQ.,a
//停止文件下载 EL,k z8
public void siteStop() ztVTXI%Kz
{ 5=o^/Vkc
bStop = true; 2@S}x@^
for(int i=0;i<nStartPos.length;i++) (Yewd/T
fileSplitterFetch.splitterStop(); }UyQGRZ=
~kW?]/$h
+tPBm{|
} 8maWF.xq
} 12 p`ZD=
//负责部分文件的抓取 uw mN!!TS
**FileSplitterFetch.java '5h`="
*/ 9=>q0D2
package NetFox; :^7w
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JxIJxhA>
import java.io.*; Nbl&al@"
import java.net.*; O3sV)
4*EMd!E=<
Ph3;;,v '
public class FileSplitterFetch extends Thread { kjYM&q
Dg&6@c|
x^1udK^re
String sURL; //File URL MblRdj6
long nStartPos; //File Snippet Start Position a_Y<daRO
long nEndPos; //File Snippet End Position x2!R&q8U>
int nThreadID; //Thread's ID K P]ar.
boolean bDownOver = false; //Downing is over hYoUZ'4
boolean bStop = false; //Stop identical jOGdq;|
FileAccessI fileAccessI = null; //File Access interface kmC@\xTp
B4.: 9Od3
;UQza ]i
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException `Gio 2gl9
{ D4VDWv
this.sURL = sURL; y_m+&Oe
this.nStartPos = nStart; aHN"I
this.nEndPos = nEnd; 8c5YX
nThreadID = id; ]}3s/NJi
fileAccessI = new FileAccessI(sName,nStartPos);//定位 \_Bj"K
} P j
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public void run() wn"}<ka
{ 9q"kM
while(nStartPos < nEndPos && !bStop) R XCn;nM4
{ Znb={hh
C]!2
9q'&tU'a=c
try{ v#,queGi
URL url = new URL(sURL); k8D_
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); K1@Pt}
httpConnection.setRequestProperty("User-Agent","NetFox"); </[.1&S+\
String sProperty = "bytes="+nStartPos+"-"; S=4o@3%$
httpConnection.setRequestProperty("RANGE",sProperty); 9xR5Jm>k
Utility.log(sProperty); 2+9VDf2
jR%*,IeB
gG?@_ie
InputStream input = httpConnection.getInputStream(); -#ZvjEaey
//logResponseHead(httpConnection); {s8c@-'
w;lpJB\
/h>g-zb
byte[] b = new byte[1024]; x3y+=aj
int nRead; Tz1^"tx9
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) =UKxf
{ _[HZ[9c!
nStartPos += fileAccessI.write(b,0,nRead); L-|l$Ti"
//if(nThreadID == 1) @:>]jp}uq
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); \V-N~_-H
} SA TX_
~P|;Y<?3
?~o`mg
Utility.log("Thread " + nThreadID + " is over!"); #*g=F4>t
bDownOver = true; j4/[Z'5ny
//nPos = fileAccessI.write (b,0,nRead); H$%MIBz>$
} ^MpMqm1?8;
catch(Exception e){e.printStackTrace ();} R,3cJ Y_%
} 1GYZ1iA
} _/1/{
G'JHimP2j
6ld4'oM
//打印回应的头信息 ">[#Ops-;$
public void logResponseHead(HttpURLConnection con) *D|a`R!Y
{ WZ'Z"'
for(int i=1;;i++) 1Dr&BXvf]8
{ 7(84j5zb
String header=con.getHeaderFieldKey(i); W\l&wR
if(header!=null) <{#_;7h"
//responseHeaders.put(header,httpConnection.getHeaderField(header)); =gj?!d`
Utility.log(header+" : "+con.getHeaderField(header)); /"X_{3dq?
else x0# Bc7y
break; 0=>$J WF
} Qj^Uz+b
} CV0id&Nv
e\6H.9=
<&\ng^Z$
public void splitterStop() 0q5J)l:
{ T<n`i~~
bStop = true; xX&B&"]5
} Jj=qC{]
KZ5%q.
}PI:O%N;
} I0mp[6
8"&!3_
d27q,2f!
/* nI3p`N8j*
**FileAccess.java *'?ZG/ (
*//文件访问(定位，写) Kg6J:HD49
package NetFox; s,Gl{
import java.io.*; ek&~A0k_o
|.@!CqJ
YYT;a$GTo
public class FileAccessI implements Serializable{ rD}g9?ut
T 6D+@i
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 boojq{cvYA
RandomAccessFile oSavedFile; 3H,x4L5j
long nPos; ] hT\"5&6
5M>h[Q"R
j-9)Sijj{
public FileAccessI() throws IOException cM%?Ot,mK"
{ @\?HlGWEf
this("",0); m.+h@
} jG1(Oe;#
hNXZL>6
z@`o(gh
public FileAccessI(String sName,long nPos) throws IOException ^os_j39N9
{ af|h4.A
oSavedFile = new RandomAccessFile(sName,"rw"); FGn"j@m0
this.nPos = nPos; Sqa9+' [
oSavedFile.seek(nPos); 5qM$ahN3wH
} lc <V_8
:of([e|u6
@1oX&#
public synchronized int write(byte[] b,int nStart,int nLen) [l-o*@
{ N[cIr{XBGN
int n = -1; +mrLMbBiD
try{ J|I*n
oSavedFile.write(b,nStart,nLen); Ovx *
n = nLen; li[[AAWVm
} p<r^{y
catch(IOException e) ZQlk 5
{ 6)1PDlB
e.printStackTrace (); Q>$B.z
} OkC.e')Vx
vhF9|('G
+JI,6)Ry
return n; syr0|K[
} 43k'96[2d
l0'Yq%Nf
Nk@-yZ@,8
} Mst%]@TG
}-tJ.3Zw
>12jUm)
/* G/JGb2I/7|
**SiteInfoBean.java uBts?02
*/ bhD-;Y!6;
package NetFox; K#k/t"r
-. *E<%
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public class SiteInfoBean { .'=S1|_(
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7@"X?uo%o
private String sSiteURL; //Site's URL pJFn 8&!J
private String sFilePath; //Saved File's Path a8TtItN
private String sFileName; //Saved File's Name %fF,Fnf2
private int nSplitter; //Count of Splited Downloading File IN/$b^Um
4Wgzp51Aq!
9"^ib9M
public SiteInfoBean() z*T41;b
{//nSplitter的缺省值为5 Osz=OO{
//default value of nSplitter is 5 80Y%C-Y:
this("","","",5); -n7@r
} lq.:/_m0
fDDpR=
<h#7;o
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 3m&r?xZs
{ oOprzxf"+Z
sSiteURL= sURL; *m]Y6
sFilePath = sPath; s=)W
sFileName = sName; 6Mk#) ebM
this.nSplitter = nSpiltter; ; s(bd#Q
WT\wV\Pu
mW]dhY 3X
} 9iT9ZfaW
A o*IshVh
/{l_tiE7
public String getSSiteURL() 6)sKg{H
{ tC'#dU`=qY
return sSiteURL; rL\}>VC)
} Rng-o!
?8$`GyjS
3~fi#{
public void setSSiteURL(String value) :JSxsA6k
{ 3F"vK
sSiteURL = value; ;q'-<O
} D,=~7/g
%!iqJ)*~
NUM!'+H_h
public String getSFilePath() 5$+7Q$Gw
{ o`,}b1lh
return sFilePath; *i*\dl
} ^nZ=B>Yn2
nY MtK
]a.e;c-
public void setSFilePath(String value) ds`YVXKH
{ V^tD@N
sFilePath = value; k-&<_ghT \
} 0(d!w*RpG
w&YUb,{Y
?J6Ek*E#
public String getSFileName() #NyO'
{ )7Hx<?P
return sFileName; RNB-W%
} Q^<amM!
N'{Yhx u
~I N g9|
public void setSFileName(String value) :kcqf,7
{ g:RS7od=,
sFileName = value; 6v{&,q
} fahQ^#&d`
rZ,3:x-:
Uy=yA
public int getNSplitter() jhz*Y}MX
{ )j'Qi^;(D
return nSplitter; )}$rgYKJ
} Ruq;:5u
3KqRw (BK
zdem}kBIe
public void setNSplitter(int nCount) @G]*]rkKb
{ 2Rys:$
nSplitter = nCount; U$DZht4>u
} Wk^{Tn/]
} B{0]v-w
FnVW%fh
fph+05.%
/* nv0D4 t
**Utility.java 851BOkRal4
*/ :)Es]wA#HZ
package NetFox; WyV,(~y
z z]~IxQ
A]Hz?i
public class Utility { y)LX?d
_GY2|x2c
3R$R?^G
public Utility() Hwd^C2v
{ VO1
hc$m1lLn
B}NJs,'FJ
} ga KZ4#
k"7ZA>5jk
//线程睡眠 CUTjRWQ
public static void sleep(int nSecond) M'|[:I.V
{ MZ0cZv$v!~
try{ g#fn(A
Thread.sleep(nSecond); 4T52vM
} )M.g<[=^
catch(Exception e) RpU i'
{ Tn,_0
e.printStackTrace (); 8S#&XS>o
} P$Yw'3v/
} V4u4{wU]
rVhfj~Ts
//日志 (e_p8[x
public static void log(String sMsg) VxOWv8}|
{ )6"p@1\u
System.err.println(sMsg); KBi(Ns#+
} 7H6Ge-u
<:(;#&<
d|87;;X|u
public static void log(int sMsg) VJA/d2Oys
{ 0gOca +&
System.err.println(sMsg); *EO*Gg0d
} 0 GFho$f
} f3vl=EA4|
Z;u3G4XlF
w?3ww7yf`
/* _"H\,7E
**TestMethod.java &RuTq6)r
*/ $uwz`N:
package NetFox; irw5<l
RI<smt.Ng
EGFP$nvq
public class TestMethod { (VkO[5j
r1.zURY
=>o !
public TestMethod() |gk4X%o6
{ ///xx/weblogic60b2_win.exe LB.B w
try{ +F,])p4,]i
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); z<P?p
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); s 7%iuP
SiteFileFetch fileFetch = new SiteFileFetch(bean); bFG?mG:
fileFetch.start(); {[bpvK
} pi70^`@'B
catch(Exception e){e.printStackTrace ();} [Djx@x
| Wj=%Ol%o
npytb*[|c
} zSMM?g^T
&&jQ4@m}j
'lEIwJV$
public static void main(String[] args) 2ER_?y
{ 37IHn6r\
new TestMethod(); $\k)Y(&
} S^i8VYK,C5
} ~[aV\r?
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