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)); $ VT)
} .C'\U[A{
for(int i=0;i<nEndPos.length-1;i++) L/i'6(="
{ z@,pT"rb
nEndPos = nStartPos[i+1]; 1SExlU
} 7kLurv
nEndPos[nEndPos.length-1] = nFileLength; #_DpiiS,.Q
} Nx 42k|8
} U#z"t&o=L
0t7N yKU
p*Z<DEh#
//启动子线程 =-r"@2HBq
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; if*V-$[I
for(int i=0;i<nStartPos.length;i++) I~&*^q6 |
{ 2P"643tz
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), LKM018H>
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), JWNN5#=fQ
nStartPos,nEndPos,i); WZ'<iI
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); >V"{]v
fileSplitterFetch.start(); E=I'$*C\D
} ]3 "0#Y
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), &W\e 5X<A
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); xrf|c
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", [U&k"s?
nEndPos = " + nFileLength); rS [4Pey
// fileSplitterFetch[nPos.length-1].start(); *j3U+HV
'gY?=,dF>
SY,ns*>1F
//等待子线程结束 RdX+:!lD
//int count = 0; tK3$,9+
//是否结束while循环 MSCH6R"5
boolean breakWhile = false; \l/(L5gY
jwI2T$
Q`k;E}x_-
while(!bStop) JN8Rh
{ aT,WXW*
write_nPos(); y4kn2Mw;
Utility.sleep(500); 7J);{ &x9h
breakWhile = true; OeQ[-e
-HF?1c
A|"T8KSMB
for(int i=0;i<nStartPos.length;i++) v?He]e'
{ -5*OSA:8x
if(!fileSplitterFetch.bDownOver) _ s 3aaOL
{ lV'?X%
breakWhile = false; 1K/HVj+'.
break; -C2!`/U
} #w;"s*
} :Racu;xf
if(breakWhile) |>ztx}\
break; )<QX2~m<
)7.)fY$
ew\:&"@2]w
//count++; ;` L%^WZ;-
//if(count>4) e#oK% {A
// siteStop(); hJSvx
} .i;.5)shsu
LH54J;7Y
3HyOQD"{
System.err.println("文件下载结束！"); QvbH " 7
} "}X+vd``
catch(Exception e){e.printStackTrace ();} /4+L2O[
} "nz\YQdg
r5gqRh}+
'-"[>`[q
//获得文件长度 Z`kVyuQ
public long getFileSize() 2sGKn a
{ NnAIL;WS
int nFileLength = -1; E:qh}wY
try{ kI"9T`owR
URL url = new URL(siteInfoBean.getSSiteURL()); qlM<X?
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); P].Eb7I
httpConnection.setRequestProperty("User-Agent","NetFox"); {`):X_$T
yV`Tw"p
u.A}&'H
int responseCode=httpConnection.getResponseCode(); jTS8 qu
if(responseCode>=400) k;cIEEdZD
{ |dxWO
processErrorCode(responseCode); k9eyl)
return -2; //-2 represent access is error ?$`kT..j,u
} \dQc!)&C9
Yz;7g8HI
3D6&0xTq
String sHeader; 53hX%{3
&B5&:ib1D
`a52{Wa
for(int i=1;;i++) R?1Z[N
{ o~'p&f
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ^Zvb3RJg
//Utility.log(in.readLine()); a=W%x{
sHeader=httpConnection.getHeaderFieldKey(i); '`;=d<'
if(sHeader!=null) Z'A 3\f
{ qMEd R;o
if(sHeader.equals("Content-Length")) 0to`=;JI
{ u"zR_CzYc
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); %KVmpWku
break; ]-t>F
} b~UWFX#U
} kB?/_a`]
else vw>(JCR
break; ktPM66`b
} z4 =OR@ h
} sf$hsPC^
catch(IOException e){e.printStackTrace ();} Y;R,ph.a
catch(Exception e){e.printStackTrace ();} g}R#0gkdk}
E-^(VZ_Xj
rV\G/)xL
Utility.log(nFileLength); UB+~K/
/*;a6S8q
'__>M>[
return nFileLength; 4IW fp&Q!
} --diG$x.
>!qtue7B
k>i`G5Dh
//保存下载信息（文件指针位置） )^8[({r~
private void write_nPos() R<fF ^^
{ p8XvfM
try{ 4RctYMz
output = new DataOutputStream(new FileOutputStream(tmpFile)); -uN{28;@
output.writeInt(nStartPos.length); 6|lsG6uf
for(int i=0;i<nStartPos.length;i++) v5@4|u3ds
{ 0Sk~m4fj(
// output.writeLong(nPos); w;Azxcw
output.writeLong(fileSplitterFetch.nStartPos); %AJ9fs4/
output.writeLong(fileSplitterFetch.nEndPos); V5-!w0{
} %h(%M'm?
output.close(); kIa16m
} 9:g A0Z
catch(IOException e){e.printStackTrace ();} _1RvK? ;.{
catch(Exception e){e.printStackTrace ();} E5A"sB
} fn/?I\
s#<fj#S
t{B@k[|
//读取保存的下载信息（文件指针位置） Z^Um\f
private void read_nPos() Z796;qk
{ u[KxI9Q
try{ >VZxDJ$R
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); G0m$bi=z
int nCount = input.readInt(); 4S*ifl
nStartPos = new long[nCount]; <BT18u\
nEndPos = new long[nCount]; Kn3Xn`P?
for(int i=0;i<nStartPos.length;i++) R`$Y]@i&B
{ 74N_>1!j
nStartPos = input.readLong(); $aEv*{$y
nEndPos = input.readLong(); I*j~5fsS'
} _QHk&-Lp
input.close(); T}z? i
} x]`F#5j
catch(IOException e){e.printStackTrace ();} >&fD:y'&
catch(Exception e){e.printStackTrace ();} Kg~D~ +j
} e}-fGtFx
66-\}8f8a
y$nI?:d
private void processErrorCode(int nErrorCode) O13]H"O_
{ `%~}p7Zu
System.err.println("Error Code : " + nErrorCode); z9&j
} Ax\d{0/oL2
_\yR/W~
]%-U~avph
//停止文件下载 Uc_}="
public void siteStop() g$2#TWW5
{ [;aM8N
bStop = true; /2d>nj
for(int i=0;i<nStartPos.length;i++) $bp$[fX(e
fileSplitterFetch.splitterStop(); sqpo5~
WI| -pzg
F0&ubspt\
} WJ-.?
} AvZ5?rN$
//负责部分文件的抓取 j;48Yya'
**FileSplitterFetch.java &?Erkc~#
*/ UW}@oP$r
package NetFox; 7xB]Z;:
>Vx_Xv`Jwb
byE0Z vDM
import java.io.*; LH}9&FfjU
import java.net.*; VJw7defc
&n8Ja@Y]
I)#8}[vK
public class FileSplitterFetch extends Thread { rSt5@f?
'hWA&Xx+
` ;mQ"lO
String sURL; //File URL ceJ#>Rj
long nStartPos; //File Snippet Start Position "9^b1UH<
long nEndPos; //File Snippet End Position \tvL<U"'
int nThreadID; //Thread's ID bh5P98s
boolean bDownOver = false; //Downing is over Wtw,YFT
boolean bStop = false; //Stop identical 6wu`;>
FileAccessI fileAccessI = null; //File Access interface >`&2]Wc)
)N~ p4kp
r?Mf3U^G
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException PfU\.[l$
{ #>KiX84
this.sURL = sURL; NwOV2E6@OW
this.nStartPos = nStart; 6q'Q?Uw^
this.nEndPos = nEnd; ,6MJW#~]
nThreadID = id; Hmm0H6&u
fileAccessI = new FileAccessI(sName,nStartPos);//定位 'MX|=K!C
} 0+qC_ISns
o:cTc:l)
@,=pG
public void run() ,J+L_S+B~
{ 9XQE5^
while(nStartPos < nEndPos && !bStop) bJ 6ivz
{ 6&'kN2
wXp:XZ:]T
QsxvA;7%
try{ wmVb0~[
URL url = new URL(sURL); 2V%z=
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); T#!% Uzz
httpConnection.setRequestProperty("User-Agent","NetFox"); U5-8It2OR
String sProperty = "bytes="+nStartPos+"-"; .]KC*2
httpConnection.setRequestProperty("RANGE",sProperty); aY,Bt
Utility.log(sProperty); jyF*JQjK4
B_[I/ ?
$ S3b<]B
InputStream input = httpConnection.getInputStream(); Ap?,y?
//logResponseHead(httpConnection); JAjiG^]
?kZ-,@h:
3mYW]
byte[] b = new byte[1024]; `Rq|*:LV
int nRead; "XV@OjrE
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Q_fgpjEh/t
{ M0C)SU5"
nStartPos += fileAccessI.write(b,0,nRead); _2`b$/)-
//if(nThreadID == 1) -Wmb M]Z
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); a%HNz_ro
} *szs"mQ/
4P)#\$d:
|6?s?tC"u
Utility.log("Thread " + nThreadID + " is over!"); xc@$z*w
bDownOver = true; d>I)_05t
//nPos = fileAccessI.write (b,0,nRead); NTZ3Np`
} w+j\Py_G"
catch(Exception e){e.printStackTrace ();} 2.Ww(`swL
} <G<5)$ S
} E <j=5|0t
6J JA"] `
S}h d,"I
//打印回应的头信息 3 ;F
public void logResponseHead(HttpURLConnection con) 2uT6M%OC
{ ,)d`_AD+5
for(int i=1;;i++) ,KM%/;1Dm
{ ` W);+s
String header=con.getHeaderFieldKey(i); OMmfTlM%
if(header!=null) ; \co{_&D
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ?-Of\fNu
Utility.log(header+" : "+con.getHeaderField(header)); =,ax"C?pR
else ,vvfk=-
break; $ eL-fg
} \VIY[6sn\M
} >{~xO 6H
WdS1v%
lU=VCuW!
public void splitterStop() l}-k>fug
{ ziO(`"v
bStop = true; fX,O9d$
} WW3Jxd
A_ &IK;-go
%YF /=l
} {_.(,Z{
mMZrBz7r
X#0yOSR
/* 5M'cOJ
**FileAccess.java 9cN@y<_I
*//文件访问(定位，写) $4ZV(j]
package NetFox; By!u*vSev
import java.io.*; FVP,$
+&f_k@+
Brs}
public class FileAccessI implements Serializable{ *wmkcifF;
nIBeZof
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 qA!4\v={
RandomAccessFile oSavedFile; {df;R|8l
long nPos; ?Q=(?yR0]
/{8Y,pZbu
@##}zku
public FileAccessI() throws IOException 4mp)v*z
{ CpX[8>&osD
this("",0); =&"pG`x
} @%u}|iF|
?uTuO
ph(LsPT-
public FileAccessI(String sName,long nPos) throws IOException q0>9T
{ `l?MmIJ
oSavedFile = new RandomAccessFile(sName,"rw"); e'G3\h}#
this.nPos = nPos; I;_T_m4.q
oSavedFile.seek(nPos); \j)c?1*$
} $$4flfx
BIx*(
hV`?, ~K
public synchronized int write(byte[] b,int nStart,int nLen) d@*dbECG
{ s/~[/2[bnf
int n = -1; ? B|i
try{ im:[ViR {
oSavedFile.write(b,nStart,nLen); 9%ct
n = nLen; m^ar:mK@
} Xu_1r8-|=b
catch(IOException e) r:0RvWif
{ Dvz 6 E
e.printStackTrace (); VY~*QF~P
} =|$U`~YB
L&NpC&>wD
qx >Z@o
return n; ;{iTSsb
} uW[AnQ1w
Z9% u,Cb
Pk5\v0vkg
} >yVrIko
^56D)A=
3#udzC
/* V5h_uGOD
**SiteInfoBean.java e>!]_B1ad
*/ 5gx;Bp^_
package NetFox; *)\y52z
5$Kv%U
.|L9}<
public class SiteInfoBean { 60>g{1]
#vy[v22
&2@Rc?!6_P
private String sSiteURL; //Site's URL !m_y@~pV#u
private String sFilePath; //Saved File's Path '5T:*Yh
private String sFileName; //Saved File's Name 'X&"(M
private int nSplitter; //Count of Splited Downloading File Avljrds+7
5c%Fb:BW=
h=YTgJ
public SiteInfoBean() F)'_,.?0
{//nSplitter的缺省值为5 Bgsi$2hI
//default value of nSplitter is 5 !VG ]~lc
this("","","",5); xQ?$H?5B<
} qIzv|Nte
eK3d_bF+
7I(QTc)*
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) <Z]j89wzDZ
{ ep48 r>
sSiteURL= sURL; |z}VP-L
sFilePath = sPath; .bh7
sFileName = sName; UY.o,I>s
this.nSplitter = nSpiltter; |P9)*~\5
@frV:%
#f=41d%
} Ix=(f0|
yG#x*\9
gK *=T
public String getSSiteURL() 5X]f}6kT
{ \)MzUOZn
return sSiteURL; nM8'="$
} %3HF_DNOY=
$Zrc-tkV
YO@~y*,
public void setSSiteURL(String value) K"Irg.
{ G-o6~"J\
sSiteURL = value; G&6`?1k
} /W}"/W9
K7qR
6k37RpgH
public String getSFilePath() Y|-&=
{ 8k Sb92
return sFilePath; /(s N@kt
} w);Bet
v&66F`
cSTL.QF
public void setSFilePath(String value) Qq.Ja%Zq
{ 5]3Mj*u\
sFilePath = value; uD4W@*PYr
} eM7F8j
>v/%R~BuX
UD2l!)rW
public String getSFileName() _*t75e$-
{ ZU7u>
return sFileName; g</Mk^CE
} <@n3vO6
`,c~M
ub4(g~E
public void setSFileName(String value) e:QH3|'y
{ j2hp*C'^
sFileName = value; gb^'u
} `7V'A
^NxKA'oWQ
fzjtaH?
public int getNSplitter() 7zNfq.Ni~
{ r8_MIGM'
return nSplitter; l>7?B2^<E
} P$/Y9o
\&v)#w
"t>H B6^
public void setNSplitter(int nCount) +5Y;JL<%/
{ ~^g*cA t}
nSplitter = nCount; %W2 o`W$
} S)^eHuXPI
} jyRz53
'z};tIOKJk
O3p<7`K<4
/* 8(-N;<Ef2
**Utility.java H ;HFen|
*/ zK:2.4
package NetFox; 6ZC~q=my
\%#luk@:
Oh7wyQiV
public class Utility { Gfle"_4m8
!@)tkhP
drB$q[Ak9
public Utility() (%]M a
{ ~#P` 7G
cMAY8$
=A/$[POr
} MnW"ksH
;'4Kg@/
//线程睡眠 }~ga86:n0
public static void sleep(int nSecond) n=h!V$X
{ ^QTkre
try{ zgSv -h+f
Thread.sleep(nSecond); `S]DHxS
} B!1L W4^
catch(Exception e) vPu{xy
{ M9(Kxux#
e.printStackTrace (); QLH6Nmk
} MBFn s/
} }Szs9-Wns
tHH @[E+h
//日志 t)l^$j!h@
public static void log(String sMsg) chU,));F
{ 3hR3)(+1
System.err.println(sMsg); 04!akPP<
} +tv"j;z
SiT5QJe
J~5+=V7OV
public static void log(int sMsg) |+aD%'|
{ r 4+%9)
System.err.println(sMsg); JjBlje
} =K6{AmG$
} ,@@FAL
%uy?@e
fSm|anuKZe
/* X0]5I0YP
**TestMethod.java v,)vW5jGI
*/ vsbD>`I
package NetFox; -+ Mh('K
~"U^N:I"
(=QiXX1r
public class TestMethod { G-RE
t",b.vki\z
{pk&dB _Bu
public TestMethod() 22v= A6 =
{ ///xx/weblogic60b2_win.exe HVM(LHm=:
try{ NYF 7Ep; _
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); .v#Tj|w^
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); E"t79dD
SiteFileFetch fileFetch = new SiteFileFetch(bean); BGL-lJrG
fileFetch.start(); \7tJ)[0aF
} c8qwsp
catch(Exception e){e.printStackTrace ();} M{`uI8vD
#j6qq3OG
_n!W4zwi
} axiP~t2
jsIT{a*]
SHUn<+/e
public static void main(String[] args) jRSY`MU}t+
{ zFO#oW,D
new TestMethod(); ]*yUb-xY
} j{H,{x
} [7=?I.\Cr7
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