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)); C0sX gM
} Vouvr<43o
for(int i=0;i<nEndPos.length-1;i++) 2VPdw@"~}
{ 55G+;
nEndPos = nStartPos[i+1]; UZWioxsKr+
} :W"~ {~#?
nEndPos[nEndPos.length-1] = nFileLength; ~jWn4 \
} ]N/=Dd+|
} S:u:z=:r
}V'}E\\
2pZXZ
//启动子线程 R &nPj~
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; UgRhWV~f0
for(int i=0;i<nStartPos.length;i++) |{&{
{ d}OTO10
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ,xw#NG6
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), imVo<Je7z(
nStartPos,nEndPos,i); UI0(=>L
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ;RH;OE,A
fileSplitterFetch.start(); 2my_;!6T[
} 8mCxn@yV
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), EHSlK5bD,
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); OP;v bZ
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", _Mi5g_
nEndPos = " + nFileLength); j9m_jv
// fileSplitterFetch[nPos.length-1].start(); ~Q*%DRd&Z-
>|J`s~?
\0A3]l
//等待子线程结束 hl;u'_AB
//int count = 0; seba9y
//是否结束while循环 CYt?,qk-r
boolean breakWhile = false; N'F77 .
gBd]B03
*tGY6=7O
while(!bStop) 52Yq
{ #`~C)=-
write_nPos(); &C:IX\
Utility.sleep(500); s'3 s^Dd
breakWhile = true; XUrXnz|>
WEAT01
mR!1DQ.\<
for(int i=0;i<nStartPos.length;i++) Plc-4y1
{ 1&\0:vA^Y
if(!fileSplitterFetch.bDownOver) ;[(oaK@+n
{ y$;/Vm_'
breakWhile = false; []D&bYpv
break; t1]K<>g
} md+nj{Ib
} =-tw5], L
if(breakWhile) 3\AU 72-
break; '-wj9OU
( B!uy`
<xup'n^7C
//count++; O8^A5,2@3>
//if(count>4) ,yC-+VL
// siteStop(); #OZ>V3k
} CZ8KEBl
rDl*d`He!
qjwxhabc
System.err.println("文件下载结束！"); /{Is0+)
} ag;Q F
catch(Exception e){e.printStackTrace ();} qjc8fP2
} Nv$R\'3
Id*Ce2B
PYQ;``~x
//获得文件长度 W=lyIb{?^0
public long getFileSize() mD/9J5:
{ @efh{
int nFileLength = -1; "_P;2N6
try{ 8<5]\X
URL url = new URL(siteInfoBean.getSSiteURL()); q$p%ZefZ
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); +\x,HsUc"
httpConnection.setRequestProperty("User-Agent","NetFox"); [2>yYr s_=
U] ~$g}!)
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int responseCode=httpConnection.getResponseCode(); FSP+?((
if(responseCode>=400) eP.wOl
{ w2Us!<x
processErrorCode(responseCode); &]V.S7LC#
return -2; //-2 represent access is error 7Sf bx~48
} H[m:0eF'5
2uzW+D6J
j~"Q3P;V
String sHeader; H-WJp<_
ksc;X$f&4
&\#sI9
for(int i=1;;i++) 1Rq,a
{ s kvGU(G}
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); i3dkYevs?
//Utility.log(in.readLine()); Yf:IKY
sHeader=httpConnection.getHeaderFieldKey(i); 5c9^-|-T
if(sHeader!=null) =MSr/O2
{ ?:pP8/y
if(sHeader.equals("Content-Length")) XYjV.j\
{ m];]7uB5=
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); tankR9(o
break; S3F;(PDzy
} w+C7BPV&
} 6RG)`bu
else l#m#c6;=
break; NYt&@Z}]
} Sw:7pByjI
} &[_g6OL
catch(IOException e){e.printStackTrace ();} Jk&3%^P{m
catch(Exception e){e.printStackTrace ();} neB\q[k
6q*9[<8
y.anl
Utility.log(nFileLength); I+BHstF5um
Bu#E9hJFvA
UGD2
return nFileLength; >d*iD
} ^b/ Z)3
?iPC*
I*%-cA%l
//保存下载信息（文件指针位置） G(Lzf(
private void write_nPos() o#;b
{ t,QyfN
try{ DD7h^-x
output = new DataOutputStream(new FileOutputStream(tmpFile)); $g@=Z"
output.writeInt(nStartPos.length); xRJ\E }/7
for(int i=0;i<nStartPos.length;i++) M.Y~1c4f
{ S\LkL]qx
// output.writeLong(nPos); *Tas`WA
output.writeLong(fileSplitterFetch.nStartPos); yGI;ye'U
output.writeLong(fileSplitterFetch.nEndPos); 4Z1ST;
} ;QWIsVz
output.close(); MPCBT!o4Z
} M:XSQ["6>V
catch(IOException e){e.printStackTrace ();} U [*FCD!~
catch(Exception e){e.printStackTrace ();} qT,Te
} fg s!v7
lAi6sPG)0
2gc/3*F8
//读取保存的下载信息（文件指针位置） YT8vP~
private void read_nPos() .+qQYDEw
{ yQU_>_!n
try{ a,xycX:U
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ]*vdSr-J
int nCount = input.readInt(); j`oy`78O
nStartPos = new long[nCount]; tU4s'J
nEndPos = new long[nCount]; 3XL#0\im?s
for(int i=0;i<nStartPos.length;i++) Qr1"Tk7s
{ ~Am,%"%\
nStartPos = input.readLong(); Cf TfL3(J
nEndPos = input.readLong(); ~KHVY)@P
} *$yR*}A
input.close(); _/F7?^j
} Y?S!8-z
catch(IOException e){e.printStackTrace ();} %Qc La//
catch(Exception e){e.printStackTrace ();} ?/BqD;{?I
} wr5AG<%(
+s(HOq)b
&]8P1{
private void processErrorCode(int nErrorCode) 9zZr^{lUl
{ ,.rs(5.z8/
System.err.println("Error Code : " + nErrorCode); !HrKXy0{
} l9}3XI.=
q'|rgT
pczug-nB
//停止文件下载 lH#u
public void siteStop() |L-]fjBbF
{ K17j$o^6KK
bStop = true; , 0imiv
for(int i=0;i<nStartPos.length;i++) h^?\xm|
fileSplitterFetch.splitterStop(); { WIJC',Y
g>Y|9Y
UADFnwR[R
} IT(lF
} Rd2qe /
//负责部分文件的抓取 #,,d>e
**FileSplitterFetch.java [ad@*KFxy3
*/ aAJU`=uq
package NetFox; OTy.VT|
IzsphBI
T@G?t0
import java.io.*; Y'yH;Mz
import java.net.*; 6`O.!|)
hakKs.U|[
vu|n<
public class FileSplitterFetch extends Thread { ^c<ucv6.
wLmhy,
"7!;KHc
String sURL; //File URL 5Y.vJz
long nStartPos; //File Snippet Start Position V@Rrn <l
long nEndPos; //File Snippet End Position E^QlJ8
int nThreadID; //Thread's ID #OIcLEn%
boolean bDownOver = false; //Downing is over aEM%R<e
boolean bStop = false; //Stop identical s}j{#xT
FileAccessI fileAccessI = null; //File Access interface A9f)tqbc
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Z9MdD>uwi
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException %C$%!C
{ kgnmGuka
this.sURL = sURL; ?!9)q.bW
this.nStartPos = nStart; yOphx07 (
this.nEndPos = nEnd; 74H)|Dkx
nThreadID = id; %70~M_
fileAccessI = new FileAccessI(sName,nStartPos);//定位 L%BNz3:Dt
} TatpXN\
}2<r,
TcIcS]w%
public void run() [K9'<Qnu
{ KAC6Snu1
while(nStartPos < nEndPos && !bStop) IOb*GTb
{ :E_g"_
z*kutZ:6Y
MNC*Glj=
try{ CsTF
URL url = new URL(sURL); 9;_sC
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 1nQWW9i
httpConnection.setRequestProperty("User-Agent","NetFox"); \Kl+ 5%L
String sProperty = "bytes="+nStartPos+"-"; %ZNI:Uh
httpConnection.setRequestProperty("RANGE",sProperty); XM1WfjE\
Utility.log(sProperty); Z3{>yYR+
7Bb9t
v5By:z
InputStream input = httpConnection.getInputStream(); Av"R[)
//logResponseHead(httpConnection); "$N#p5
;u;#g
qR(\5}
byte[] b = new byte[1024]; VTG9$rQZ
int nRead; n;(\5{a
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ]F;f`o
{ o=21|z
nStartPos += fileAccessI.write(b,0,nRead); qp/v^$EA
//if(nThreadID == 1) BnCbon)
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); .C&ktU4
} SF&BbjBE0
*"D3E7AO
5"HVBfFk
Utility.log("Thread " + nThreadID + " is over!"); ?*E'^~,H)
bDownOver = true; t"k*PA
//nPos = fileAccessI.write (b,0,nRead); -M[$Zy^
} G]fRk^~
catch(Exception e){e.printStackTrace ();} 29!q!g|
} ?%`@ub$
} wS4.8iJ
RT)d]u
<z]cyXv/
//打印回应的头信息 J13>i7]L%
public void logResponseHead(HttpURLConnection con) ANJ$'3tg
{ '<rZm=48
for(int i=1;;i++) zRq-b`<7V
{ {P{bOe
String header=con.getHeaderFieldKey(i); V>R8GSx
if(header!=null) [* @5\NWR}
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ;k7xMZs
Utility.log(header+" : "+con.getHeaderField(header)); L1ieaKw
else lmfi
break; FP;Ccl"s
} s0DGC
} jJuW-(/4[
Q.]}]QE
c8L~S/t
public void splitterStop() %7"X(Ts7B
{ ^;/b+ /B0
bStop = true; sB^<6W!`(
} TYJ:!
3~}uqaGt
3jlh}t>$l
} zY|t0H
`0P$#5?
#;%JT
/* kMtwiB|7j
**FileAccess.java r41\r,`Dj
*//文件访问(定位，写) O)ME"@r@:
package NetFox; 'h^0HE\~p
import java.io.*; MxGu>r
XVKfl3'%
|g #K]v
public class FileAccessI implements Serializable{ r:F
/C>wd
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 COW}o~3-4
RandomAccessFile oSavedFile; "\}@gV#r$A
long nPos; xER\ZpA:,
rb1`UG"h$
>TQH|}|6(y
public FileAccessI() throws IOException +m8!U=Zi
{ =|I>G?g-
this("",0); |lJX 3
} \>CYC|
f}1&HI8r
:{IO=^D=$
public FileAccessI(String sName,long nPos) throws IOException <^zHE=h"
{ HYD"#m'TkB
oSavedFile = new RandomAccessFile(sName,"rw"); >B2:kY F
this.nPos = nPos; WDg+J
oSavedFile.seek(nPos); M#~Cc~oT
} w:?oTuw
kAu+zX>S+
pek%08VSEU
public synchronized int write(byte[] b,int nStart,int nLen) wi4=OU1L)a
{ PB#fP_0C
int n = -1; mml<9fbH
try{ 6(G?MW.
oSavedFile.write(b,nStart,nLen); Gi "941zVl
n = nLen; <L`"!~Q
} Y]L9Y9
catch(IOException e) iVG-_RsKK
{ ^my].Qpt
e.printStackTrace (); *cC_j*1@
} rFC" Jx
"g'jPwFG
J41G&$j(
return n; z.Y$7bf)
} d)pV;6%[$q
QF&W`c
r=6v`)Qr
} /)dFK~
>2]JXLq
'A:x/iv}^
/* #*TEq
**SiteInfoBean.java `;>= '"O!\
*/ s1e:v+B]
package NetFox; :PtF+{N>
"dI;
(y M^
public class SiteInfoBean { /r-aPJX
Pv<24:ao
v@wb"jdFi$
private String sSiteURL; //Site's URL e0J6Ae4V[
private String sFilePath; //Saved File's Path (ZY@$''
private String sFileName; //Saved File's Name \mV'mZ9>
private int nSplitter; //Count of Splited Downloading File +QE^\a
1}tbH[
^|TG$`M(w
public SiteInfoBean() h;-yU.(w
{//nSplitter的缺省值为5 $2u 'N:o
//default value of nSplitter is 5 (sQr X{~
this("","","",5); ak:ibV
} 1&P<
?gwUwOV"
@"o@}9=d
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) #?XQ7Im
{ n_B"-n
sSiteURL= sURL; |U_]vMq
sFilePath = sPath; I8QjKI (
sFileName = sName; ,9P:Draxs`
this.nSplitter = nSpiltter; IXb}AxBf
=&},;VOh
JXw^/Y$
} ~j-cS J3
#Jna6
in(U:04
public String getSSiteURL() zLF?P3^
{ m~dC3}e8/?
return sSiteURL; 8@PX7!9
} lt_']QqU
E"L2&.
ki{3IEOr}
public void setSSiteURL(String value) !o>H1#2l
{ }=v)Js
sSiteURL = value; NNF>Xa`9,
} B}eA\O4}I
UK{irU|\
F {B\kq8
public String getSFilePath() m~>Y{F2
{ 3 E3qd'
return sFilePath; _$p$")
} $z$u{
4]/7 )x?R
p2N:;lXM
public void setSFilePath(String value) I(S)n+E
{ Cn_$l>
sFilePath = value; 5BR2?hO4
} wP57Pf0
[j"9rO" +
*#TYqCc+g
public String getSFileName() {VP$J"\e
{ k64."*X
return sFileName; JMCW}bA
} qiZO _=0
NWd<+-pC6
!bC+TYsU
public void setSFileName(String value) (oJ9k[(
{ `juLQH
sFileName = value; ZbT/$\0(6
} KE1ao9H8wR
zh$}~RG[
l?iSxqdT
public int getNSplitter() \@>b;4Fb+N
{ 87WBM;$&s
return nSplitter; m{7^EF
} yi^b)2G
'SYo_!
[|~2X>
public void setNSplitter(int nCount) 9z I.pv+]
{ `y+-H|%?
nSplitter = nCount; @Eb2k!T
} ~Xlrvb}LP
} x'zBK0i
l_j4DQBRV
cD4 kC>P*
/* [I:KpAd/
**Utility.java huudBc A[
*/ 5`]UE7gT
package NetFox; nr)c!8
"Pl9nE
Fxc)}i`
public class Utility { dDDGM:]
kF;5L)o
hfcIvs/!
public Utility() azP+GM=i7
{ >23-
efG6v
"C?5f]T
} F/1#l@qN
+ <c^=&7Lq
//线程睡眠 3jogD
public static void sleep(int nSecond) E1&b#TE6O
{ ICB~_O5
try{ [~\PQYm'
Thread.sleep(nSecond); CU:o*;jP
} =V97;kq+v
catch(Exception e) 1ZJQs6
{ N4K8 u'f^
e.printStackTrace (); _28<m JfG
} \tyg(srw0
} d/74{.
O8U<{jgAG
//日志 B$?qQ|0:=
public static void log(String sMsg) $3X-rjQtW
{ O|cu.u|
System.err.println(sMsg); %~NH0oFO
} ZAuWx@}
l$*=<tV
Q{QYBh&
public static void log(int sMsg) INSkgOo
{ Y`6rEA0
System.err.println(sMsg); GO! uwo:
} fWGOP~0
} 3E^M?N2oc
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QIB>rQCceo
/* IgL_5A
**TestMethod.java *FR$vLGn
*/ qP*}.Sqk7
package NetFox; utlpY1#q/
r'BAT3
'j%F]CK
public class TestMethod { 'rb'7=z5
.r+hERcB
(IbW;bV
public TestMethod() [O ",
{ ///xx/weblogic60b2_win.exe vQ@2FZzu>
try{ iO1nwl !#
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); aH_6s4+:
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ]>i~6!@
SiteFileFetch fileFetch = new SiteFileFetch(bean); I-NN29Sk
fileFetch.start(); E{Pgf8
} 1U\$iy8}
catch(Exception e){e.printStackTrace ();} H/~?@CE(YC
ps:f=6m2
!wLg67X$ -
} 2_QN&o ~h
oh#N 0 0X
&ogt2<1W
public static void main(String[] args) ]"fsW 9s
{ > ^[z3T
new TestMethod(); PHM:W%g:
} "L&k)J
} g+zJ?
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