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)); l Q]&:%^\
} = I,O+^
for(int i=0;i<nEndPos.length-1;i++) _G|hKk^,
{ U&yXs'3a&
nEndPos = nStartPos[i+1]; onRxe\?D(
} ?:vp3f#
nEndPos[nEndPos.length-1] = nFileLength; &PaqqU.
} S<rdPS*P
} veAg?N<c p
'DO^($N
7yD=~l\Bbs
//启动子线程 (4cWq!ax<$
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; $h`(toTyF
for(int i=0;i<nStartPos.length;i++) Ni#!C:q
{ X1&Ug^
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 3sIW4Cs7)U
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), reR><p
nStartPos,nEndPos,i); 0{^vqh.La
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Z"#eN(v.N
fileSplitterFetch.start(); >J[Bf9)>
} dU1w)Y
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 0<_|K>5dS|
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); hr_ 5D
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", F-[zuYGp
nEndPos = " + nFileLength); M #'br<]
// fileSplitterFetch[nPos.length-1].start(); C~4_Vc*
[ -"o5!0<
\95qH,w)T
//等待子线程结束 _;(`u!@/{
//int count = 0; nlmc/1C
//是否结束while循环 fZ1v|
boolean breakWhile = false; EBlfwFd
R,R[.2Vi
5OeTOI()&5
while(!bStop) bwo-9B
{ _OV\W'RrA
write_nPos(); E}AOtY5a
Utility.sleep(500); 9<u^.w
breakWhile = true; U"$Q$ OFs
y6NOHPp@
#=F"PhiX`
for(int i=0;i<nStartPos.length;i++) uw!
{ !`=ms1%U
if(!fileSplitterFetch.bDownOver) K*iy^}
{ Ay)q %:qx
breakWhile = false; <"A|Xv'Q
break; !<r+h,C
} 8|^dM$
} uo0g51%9
if(breakWhile) j,%@%upM
break; r@N 0%JZZ
_svEPHU
$jT&]p
//count++; Y<|!)JLB2
//if(count>4) )006\W|t9
// siteStop(); Td#D\d\R
} T=r-6eN
I)#=#eI*:
fxfzi{}uj
System.err.println("文件下载结束！"); Y g>W.wA
} +./c=o/v
catch(Exception e){e.printStackTrace ();} lv -z[
} N]n]7(e+0C
i0F.c\
VBc[(8o
//获得文件长度 kN3T/96
public long getFileSize() |GuIp8~
{ \zj _6Os
int nFileLength = -1; f[,9WkC
try{ fw>@:m_bK
URL url = new URL(siteInfoBean.getSSiteURL()); *M5: \+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); bqugo
httpConnection.setRequestProperty("User-Agent","NetFox"); TDI8L\rr
0kN;SSX!
O%)@> 5#S
int responseCode=httpConnection.getResponseCode(); g\MHv#v*k
if(responseCode>=400) IV{,'+hT
{ <S~_|Y*v
processErrorCode(responseCode); (Wkli:Lq
return -2; //-2 represent access is error e&[gde(
} =H*}{'#
bc}X.IC
*8}Y0V\s
String sHeader; Hw"ik6
4)D#kP
jvx9b([<sG
for(int i=1;;i++) 3/IQ]8g"
{ ~ILig}I
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); vQrce&
//Utility.log(in.readLine()); QX(x6y>Q
sHeader=httpConnection.getHeaderFieldKey(i); 97:1L4w.(
if(sHeader!=null) \RN,i]c-g/
{ NfLvK o8
if(sHeader.equals("Content-Length")) /x.TF'Z*
{ 1|Y(XB^os(
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); gr %8 O-n
break; ]D^dQ%{
} "sLdkd}dj
} tB.;T0n
else 1lyJ;6i6L
break; A7U'>r_.
} H"(:6 `
} Mr'}IX5
catch(IOException e){e.printStackTrace ();} 8?] :>
catch(Exception e){e.printStackTrace ();} 3_=~7B) 8
Cpaeo0Oq
Wd4fIegk
Utility.log(nFileLength); pM~Xh ]/
Myss$gt}
1"46OCu{
return nFileLength; 2=ZR}8}9Q:
} \3K6NA!L
=/=x"q+X
3ojK2F(1D
//保存下载信息（文件指针位置） Wu)ATs}
private void write_nPos() }@yvw*c
{ 6QdNGpN
try{ IV^LYu
output = new DataOutputStream(new FileOutputStream(tmpFile)); ^&<~6y}U^
output.writeInt(nStartPos.length); G],+?E_,
for(int i=0;i<nStartPos.length;i++) LLmgk"
{ 1_:1cF{w
// output.writeLong(nPos); N>`+{
output.writeLong(fileSplitterFetch.nStartPos); C>cc!+n%H
output.writeLong(fileSplitterFetch.nEndPos); Ff>Y<7CQ v
} qx 3.oU
output.close(); c?) pn9
} 7UHqiA`L
catch(IOException e){e.printStackTrace ();} qGkrG38K
catch(Exception e){e.printStackTrace ();} yb/< 7
} QxnP+U~N
Bir}X
Td[w<m+p<P
//读取保存的下载信息（文件指针位置） Z{#^lhHx
private void read_nPos() cNC\w%
{ /og}e~q
try{ Js+d4``W
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); M)Rp+uQ
int nCount = input.readInt(); bI[!y#_z4
nStartPos = new long[nCount]; fLI@;*hL0
nEndPos = new long[nCount]; 7qE V5!
for(int i=0;i<nStartPos.length;i++) >0 !J]gK
{ ~p;<H
nStartPos = input.readLong(); N=D Ynz_~
nEndPos = input.readLong(); JmNeqpbB`w
} #BS]wj2#
input.close(); Qm`f5-d
} CW\o>yh
catch(IOException e){e.printStackTrace ();} 'lC"wP&$
catch(Exception e){e.printStackTrace ();} t)XV'J
} ?^BsR
R'dF<&Kj|
3\=8tg p
private void processErrorCode(int nErrorCode) 5YS`v#+
{ "EEE09~l\
System.err.println("Error Code : " + nErrorCode); :^%soEi
} j,/o0k,
_Fl]zs<
74gU4T
//停止文件下载 WY 2b
public void siteStop() w**.8]A"N
{ s+zb[3}
bStop = true; /bCrpcH
for(int i=0;i<nStartPos.length;i++) a]X6)6
fileSplitterFetch.splitterStop(); R2]?9\II
@2$PU{dH
f~Kln^
} *\VQ%_wg
} }i[i{lKj
//负责部分文件的抓取 yE"hgdL
**FileSplitterFetch.java 2gt08\
*/ *otJtEI>6
package NetFox; "Wi`S;
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S}Mxm2
import java.io.*; $Fr2oSTT)
import java.net.*; ?-@hNrx
`dL9sfj>
1Za\T?V
public class FileSplitterFetch extends Thread { /c'#+!19
f7s]:n*Ih
QJ"Bd`wc
String sURL; //File URL O)9T|, U
long nStartPos; //File Snippet Start Position yvH:U5%
long nEndPos; //File Snippet End Position Q;5\( 0w5
int nThreadID; //Thread's ID m7M*)N8
boolean bDownOver = false; //Downing is over y~-?
boolean bStop = false; //Stop identical Q 5@~0
FileAccessI fileAccessI = null; //File Access interface %{}Jr`
<EBp X
PI{sO |
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException h+Q==
{ aaaC8;.
this.sURL = sURL; u8?ceM^r
this.nStartPos = nStart; ie$=3nZJ}
this.nEndPos = nEnd; wh*OD
nThreadID = id; ~(%G;fZ?x
fileAccessI = new FileAccessI(sName,nStartPos);//定位 .5dZaI)
} K/%aoTO}
sWX
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public void run() *K+*0_
{ S>"dUM
while(nStartPos < nEndPos && !bStop) ~Snw':
{ *uv\V@0
pixI&iQ
P{qn@:
try{ I9u=RIs
URL url = new URL(sURL); tjTF?>^6|
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ';lO[B
httpConnection.setRequestProperty("User-Agent","NetFox"); u#P7~9ZG-
String sProperty = "bytes="+nStartPos+"-"; sV*Q8b*
httpConnection.setRequestProperty("RANGE",sProperty); A{c6XQR~z
Utility.log(sProperty); ,%jJ ,G,
/z'j:~`E
nut7b
InputStream input = httpConnection.getInputStream(); CjST*(,b
//logResponseHead(httpConnection); S\X_!|
z[k2&=c
N&ddO-r[s
byte[] b = new byte[1024]; (%r:PcGMEV
int nRead; A9R}74e4g
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) I3L1|!
{ 7dakj>JM
nStartPos += fileAccessI.write(b,0,nRead); Th8Q~*v
//if(nThreadID == 1) vIG,!^*3
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); L{Th>]X
} e-s@@k
ECSC,oJ
qJK^i.e
Utility.log("Thread " + nThreadID + " is over!"); Kr#=u~~M
bDownOver = true; TcIUo!:z
//nPos = fileAccessI.write (b,0,nRead); dHu]wog
} 4 '+)9&g
catch(Exception e){e.printStackTrace ();} NMDNls&)k
} Z/I!\
} Q\rqG
i3GvTg-X
t"L:3<U7
//打印回应的头信息 Rsulp#['
public void logResponseHead(HttpURLConnection con) 54OYAkPCk
{ Po_9M4kU
for(int i=1;;i++) a=J?[qrx
{ _+. t7q^
String header=con.getHeaderFieldKey(i); z=xHk|+'
if(header!=null) 226s:\d
//responseHeaders.put(header,httpConnection.getHeaderField(header)); a} /Vu"
Utility.log(header+" : "+con.getHeaderField(header)); j NY8)w_
else L=p.@VSZ
break; J8%|Gd0#4
} w iq{Jo#
} -`RJk(
8fN0"pymo
i~,k2*o
public void splitterStop() 4 hj2rK'y
{ U%4g:s
bStop = true; 4/jY;YN,2
} 70NHU;&N
j\vK`.z
RpXQi*c0
} cC[n~OV
TM}F9!*je
? vlGr5#
/* K c<z;
**FileAccess.java ArEpH"}@
*//文件访问(定位，写) {$t*Mb0
package NetFox; Yyo|W;a]
import java.io.*; "tark'
)k1,oUx
Pjy?&;GvT
public class FileAccessI implements Serializable{ t[maUy_A
D6]$P%t9
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 @r43F$bcqo
RandomAccessFile oSavedFile; 5 QeGx3'
long nPos; IX(yajc[~M
%(Ys-GeGr
n96gDH*
public FileAccessI() throws IOException )eEvyU
{ OT[m g4&
this("",0); Z)A+ wM
} C]H <L#)ZU
<f6PULm
t/1NTa
public FileAccessI(String sName,long nPos) throws IOException 55DzBV
{ _PbfFY #
oSavedFile = new RandomAccessFile(sName,"rw"); h%s
this.nPos = nPos; Ltw7b
oSavedFile.seek(nPos); \i+h P1mz
} lnWiE}F
#<PdZl R
Uq.~3V+u
public synchronized int write(byte[] b,int nStart,int nLen) 5)7mjyo%
{ gJxVU41
int n = -1; UK>=y_FYO
try{ I 6YT|R
oSavedFile.write(b,nStart,nLen); 5#)<rK
n = nLen; }?J5!X
} mv?H]i`N
catch(IOException e) -l@W)?$
{ $tHwJ!<$&
e.printStackTrace (); PJ@,01
} Vk_&W.~
&i^NStqu
&n.uNe
return n; Z{4aGp*
} "EYjY->
8ysK VF
[0ffOTy
} Ti|++oC/&
T\!SA
qetP93N_*
/* RhNaYO
**SiteInfoBean.java R(83E B~_
*/ ]MLLr'6?
package NetFox; K_|~3g
Fg\| e%
;u};&sm
public class SiteInfoBean { %)Uvf`Xhh4
H\+c'$
s!/holu
private String sSiteURL; //Site's URL _#D\*0J
private String sFilePath; //Saved File's Path N3yB1_
private String sFileName; //Saved File's Name Qy^z*s
private int nSplitter; //Count of Splited Downloading File Y-3[KHD
T[XP\!z]B!
c`i=(D<
public SiteInfoBean() Ym.l@(
{//nSplitter的缺省值为5 vMX6Bg8
//default value of nSplitter is 5 Dyk[ug5
this("","","",5); X'#$e{
} r d6F"W
(OyY_`
n;kciTD%wK
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 8gbm"!
{ |aS~"lImh
sSiteURL= sURL; +dgo-)kP(_
sFilePath = sPath; Y%)h)El
sFileName = sName; YNg\"XjJM<
this.nSplitter = nSpiltter; F!)M<8jL&9
02W4-*)
rO(TG
} nGv23R(?G
'9 *|N=
>'ksXA4b
public String getSSiteURL() XewXTd#x
{ (~G5t(+
return sSiteURL; 1<W4>~,wj
} jom}_
S!jF:Uc
hJ;f1dZ7}
public void setSSiteURL(String value) jSie&V@px
{ X;OsH
sSiteURL = value; P /c Q1
} nIyROhZ
L}}=yh6r
i'W_;Y}
public String getSFilePath() HJfQ]p'nK2
{ @],6SKbG6
return sFilePath; pcI&
} )IFl 0<d
-E8ntY-
nDHHYp
public void setSFilePath(String value) ?kL|>1TY
{ YN,y0t/cQ
sFilePath = value; I&TTr7
} Gur8.A;Y
{cR_?Y@
~\IF9!
public String getSFileName() 6R1wn&8
{ V!T^wh;
return sFileName; z5XYpi_;[
} zwM"`z
Js\-['`
1MbY7!?PG
public void setSFileName(String value) S}oG.r 9
{ VHXI@UT*
sFileName = value; K&=1Ap
} w^06z,
.S~@BI(|<
A",eS6
public int getNSplitter() zKIGWH=qqm
{ U91 &|
return nSplitter; U7^7/s/.
} )Rjb/3*!
cC^W2\
7JbY}@
public void setNSplitter(int nCount) R[x7QlA;
{ kUNj4xp)
nSplitter = nCount; 4bP13f
} Q;4}gUmI$
} iaY5JEV:CA
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wk" l[cH>
/* V?OuIg%=:
**Utility.java b<[jaI0
*/ s(Z(e %
package NetFox; >BBl7
2zz,(RA
&|)hCJu
public class Utility { 4w'lu"U
Ve)ClH/DW
yH*hL0mO
public Utility() xpF](>LC(
{ WrNLGkt
85'nXYN{d
5?Bc Y;
} <3b'm*
f0vJm
//线程睡眠 T'E] i!$
public static void sleep(int nSecond) u^Vh.g]
{ K4C^m|e
try{ HN{zT&
Thread.sleep(nSecond); hi!`9k
} UVrQV$g!
catch(Exception e) z5'ZN+
{ Ejv%,q/T(
e.printStackTrace (); xOythvO
} {3LA%xO
} TXjloGv^
$_sYfU9
//日志 6JhMkB^h
public static void log(String sMsg) uVGa(4u}
{ K1OkZ6kl
System.err.println(sMsg); []zua14F6
} K/^ +eoW(
)n( Q
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public static void log(int sMsg) 3Hw[s0[$
{ ;\qXbL7
System.err.println(sMsg); GX }q9
} `N}d}O8
} rFey4zzz
[[WF0q
Zsj`F9*e
/* =\Iu$2r`
**TestMethod.java }$&xTW_
*/ L2fZ{bgy
package NetFox; ^/toz).Q
_7"5wB?|+
zT[6eZ8m
public class TestMethod { ]]2k}A[-I
\K7t'20
oh~:,
public TestMethod() _'!kuE,*1
{ ///xx/weblogic60b2_win.exe m|O1QM;T
try{ &w85[zs
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); _w!a`w*3
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); l+'F_a
SiteFileFetch fileFetch = new SiteFileFetch(bean); 6o=G8y
fileFetch.start(); %d2!\x%bG
} |quij0_'e
catch(Exception e){e.printStackTrace ();} lr~0pL
*jITOR!uF`
y9L14
} QR0(,e$Dl
tU@zhGb
eGL<vX
public static void main(String[] args) ]s_8A`vm
{ 3@<zg1.9-
new TestMethod(); 5l{Ts04k%
} Z[?mc|*x
} V '.a)6
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