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)); |_<'qh
} d3nx"=Cy0I
for(int i=0;i<nEndPos.length-1;i++) t=-t xnlr<
{ nqp:nw
nEndPos = nStartPos[i+1]; /mdPYV
} jCJbmEfo9@
nEndPos[nEndPos.length-1] = nFileLength; <5Ye')+
} FWi c/7
} g&79?h4UXQ
q5Bj0r[/o
,5Vc
//启动子线程 \IL;}D{
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; fPW|)e"
for(int i=0;i<nStartPos.length;i++) ~RdD6V
{ '7'*+sgi$
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Mx-? &
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), fG *1A\t]
nStartPos,nEndPos,i); P4\{be>e
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); "PFczoRZ
fileSplitterFetch.start(); >M}\_c=
} | c:E)S\
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), R04%;p:k#
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 9S<87sO
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", FJ/>=2^B
nEndPos = " + nFileLength); xH,D bAC;
// fileSplitterFetch[nPos.length-1].start(); 2&e2/KEWR
RFsd/K;Zp
[RAzKzC\M
//等待子线程结束 %VV\biO]
//int count = 0; rNi]|)-ET
//是否结束while循环 4$5d*7
boolean breakWhile = false; t:NYsL
2 }9of[
(31ia"i%
while(!bStop) :Dh\
{ j{U#g8
write_nPos(); LnwI 7uvq
Utility.sleep(500); :,<G6"i
breakWhile = true; sIM^e
S!LLC{
|b BA0.yS
for(int i=0;i<nStartPos.length;i++) 4qd =]i
{ -\6";_Y
if(!fileSplitterFetch.bDownOver) |UudP?E
{ $0kuR!U.N
breakWhile = false; [N35.O6P6u
break; 5s5GBJ?
} gI~4A,
} AQUl:0!
if(breakWhile) \n&l
break; iY|zv|;]=
{r.KY
'8k{\>
//count++; '7Ad:em
//if(count>4) ^R g=*L
// siteStop(); ^|b]E
} [!g$|
iXF iFsb
mJ'Q9x"
System.err.println("文件下载结束！"); B-R& v8F
} [Iwb7a0p
catch(Exception e){e.printStackTrace ();} m L#%H(
} xr;:gz!h
""Ub^:ucD
hc2AGeZr
//获得文件长度 >}uDQwX8
public long getFileSize() *y}<7R
{ $] gwaJ:
int nFileLength = -1; p)x*uqSd
try{ @4O;dFOQ)
URL url = new URL(siteInfoBean.getSSiteURL()); ZaNZUVBh
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !R b
httpConnection.setRequestProperty("User-Agent","NetFox"); ~x(1g;!^
p aQ"[w
Wl29xY}`{!
int responseCode=httpConnection.getResponseCode(); We8n20wf<
if(responseCode>=400) #`g..3ey
{ E$4_.Z8sRw
processErrorCode(responseCode); |vGb,&3
return -2; //-2 represent access is error M0B6v}^H
} LH:M`\(DL1
\68x]q[
Dc1tND$X3g
String sHeader; OBCH%\;g
<P%<EgOE
q2$-U&
for(int i=1;;i++) ]_hrYjX;
{ GKk>;X-
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 96VJE,^h
//Utility.log(in.readLine()); ~!Ar`= [
sHeader=httpConnection.getHeaderFieldKey(i); 8et*q3D7`
if(sHeader!=null) brdfjE8
{ ,GU|3
if(sHeader.equals("Content-Length")) ~Z{IdE
{ ( !THd
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 'Nqa=_<WW
break; E7CeE6U
} ,Ky-3p>
} bV3az/U
else I7S#vIMXR.
break; "3?N*,U_
} @W|N1,sp
} 8Qo~zO
catch(IOException e){e.printStackTrace ();} yF _@^V
catch(Exception e){e.printStackTrace ();} m|CB')
u2FD@Xq?
<=yqV]JR
Utility.log(nFileLength); &az :YTq
t_+Xt$Q7C
='\Di '*
return nFileLength; +L]$M)*0&
} TV['"'D&i
i3SrsVSG
{9,!XiF.:
//保存下载信息（文件指针位置） )-u0n],
private void write_nPos() `\pv^#5HV9
{ 9>OPaLn
try{ W ZAkp|R
output = new DataOutputStream(new FileOutputStream(tmpFile)); 'g@Yra&09
output.writeInt(nStartPos.length); @[=K`n:n_
for(int i=0;i<nStartPos.length;i++) (b*PDhl`+
{ ,$,c<M
// output.writeLong(nPos); KJs/4oR;
output.writeLong(fileSplitterFetch.nStartPos); q!OB?03n
output.writeLong(fileSplitterFetch.nEndPos); 1Z$` }a
} K<g<xW*X
output.close(); Ofm?`SE*|
} IQm[,Fh
catch(IOException e){e.printStackTrace ();} >QcIrq%=
catch(Exception e){e.printStackTrace ();} Vzmw%f)_+
} 7<Yf
L3@upb
%77X/%.Y
//读取保存的下载信息（文件指针位置） $*k9e^{S
private void read_nPos() I\8F.J1_
{ Jfe<$-$$7
try{ Ed>Dhy6\r
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); O'i!}$=g
int nCount = input.readInt(); -,Oq=w*EV
nStartPos = new long[nCount]; U?[_ d
nEndPos = new long[nCount]; p_g#iH!*
for(int i=0;i<nStartPos.length;i++) 7C::%OF~7
{ G%q^8#
nStartPos = input.readLong(); BPwn!ii|
nEndPos = input.readLong(); wJr5[p*M
} N}/|B}
input.close(); #J):N
} +%'!+r l
catch(IOException e){e.printStackTrace ();} en?J#fz
catch(Exception e){e.printStackTrace ();} 6 o!*bWh
} ' ~F
q\r@x-&g+
qx;8Hq(E[
private void processErrorCode(int nErrorCode) |u@/,x/t
{ zQ=c6xvm8
System.err.println("Error Code : " + nErrorCode); gd,3}@@SH
} T!F0_<
5dNM:1VoE
d8p<f+
//停止文件下载 M#CYDEB
public void siteStop() c2o.H!>
{ -yJ%G1R
bStop = true; %p(!7FDE2n
for(int i=0;i<nStartPos.length;i++) ~M!9E])
fileSplitterFetch.splitterStop(); Y;uQq-CP
N6%wHNYZ
^F?}MY>
} .m^L,;+2
} e%wzcn
//负责部分文件的抓取 {pR4+g
**FileSplitterFetch.java ~ 7^#.
*/ xaw)iC[gI{
package NetFox; |Vj@;+/j
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)/{zTg8$?/
import java.io.*; =U- w!uW
import java.net.*; R?E< }\!
Xk]:]pl4W
/]@1IC{Lk
public class FileSplitterFetch extends Thread { a:V2(nY
2Vwv#NAV k
1!P\x=Nn_
String sURL; //File URL IBn+42V
long nStartPos; //File Snippet Start Position Hdxon@,+cd
long nEndPos; //File Snippet End Position jY|fP!?[
int nThreadID; //Thread's ID m5'nqy F
boolean bDownOver = false; //Downing is over .I#ss66h
boolean bStop = false; //Stop identical {Y7dE?!`7
FileAccessI fileAccessI = null; //File Access interface ,jc')#]9B
- fx?@
&&s3>D^Ta
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException f$|AU-|<
{ Ix59(g
this.sURL = sURL; Gtm|aR{OS
this.nStartPos = nStart; %={[e`,
this.nEndPos = nEnd; {n'+P3\T:
nThreadID = id; .gP}/dj
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ;+3XDz v
} 7+2DsZ^6MW
KM:k<pvi
8TH fFL
public void run() XN Gw@$
{ Q?xCb
while(nStartPos < nEndPos && !bStop) q,%lG$0v
{ g-8D1.U
$uj3W<iw3E
>&Ios<67g
try{ OC5\3H
URL url = new URL(sURL); nb|KIW
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ,CED%
httpConnection.setRequestProperty("User-Agent","NetFox"); p2I9t|
String sProperty = "bytes="+nStartPos+"-"; l RM7s(^l
httpConnection.setRequestProperty("RANGE",sProperty); tMDJ,rT
Utility.log(sProperty); 6!T9VL\=H
/YrBnccqD
q?0&&"T}
InputStream input = httpConnection.getInputStream(); =&,<Co1hF
//logResponseHead(httpConnection); +aoenUm5
eR|u']Em>T
$O[$<D%H
byte[] b = new byte[1024]; AQU^7O
int nRead; bZ-_Q
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) gCjW !t
{ L}hc|(:
nStartPos += fileAccessI.write(b,0,nRead); Gzw9E.Hk
//if(nThreadID == 1) ^/M-*U8ab
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); l+XTn;cS
} sogdM{tz\
6cVJu%<V
jV 982Y
Utility.log("Thread " + nThreadID + " is over!"); [~Vj(H=KwI
bDownOver = true; $Le|4Hj
//nPos = fileAccessI.write (b,0,nRead); J-U5_>S
} (ptk!u6
catch(Exception e){e.printStackTrace ();} &peUC n
} w'Vm'zo
} .EB'n{zxd
IZSJ+KO
<nk7vo?Ks
//打印回应的头信息 e anR$I;Yj
public void logResponseHead(HttpURLConnection con) <_>xkQbn2
{ <_ruVy0]
for(int i=1;;i++) {^*K@c
{ j0uu*)Rk
String header=con.getHeaderFieldKey(i); u5O`|I@R
if(header!=null) <.knM
//responseHeaders.put(header,httpConnection.getHeaderField(header)); AV]7l}-
Utility.log(header+" : "+con.getHeaderField(header)); ; nc3O{rU
else nAT,y9&
break; `P *wz<
} N/x]-$fl
} Em]2K:
ANuO(^
76eF6N+%}t
public void splitterStop() `3?5Z/,y
{ ,k |QuOrCh
bStop = true; VXP@)\!
} r>_40+|&
m'PU0x
T8W;Lb9hQ
} E]c0+rh~
pZ)N,O3
FByA4VxB
/* \<u
**FileAccess.java +cwuj
*//文件访问(定位，写) 8Xx4W^*_
package NetFox; 5MHcgzyp
import java.io.*; #D ]P3
:>K8oE
S.R|Bwj}(Y
public class FileAccessI implements Serializable{ }'WEqNuE
9,cMb)=0
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 n%K^G4k^
RandomAccessFile oSavedFile; rGmxK|R
long nPos; rr^?9M*{V
dGG8k&
bZlKy`Z
public FileAccessI() throws IOException K:q|M?_
{ MRN=-|fV^
this("",0); :-tMH02c
} +[2ep"5H
3,^.
HB*H%>L{"B
public FileAccessI(String sName,long nPos) throws IOException t_kRYdW9
{ Y+nk:9
oSavedFile = new RandomAccessFile(sName,"rw"); ' '<3;
this.nPos = nPos; jT*?Z:U
oSavedFile.seek(nPos); 7-VP)|L#G
} *X\J[$!
0q o]nw
3W3)%[ 5
public synchronized int write(byte[] b,int nStart,int nLen) f-`C1|\w
{ ]XjL""EbC
int n = -1; +lw8YH
try{ 2?nEHIUT
oSavedFile.write(b,nStart,nLen); cnz+%Y N
n = nLen; '1"vwXJ"
} v(P5)R,
catch(IOException e) g+]o=@
{ z#*>u
e.printStackTrace (); Oh5aJ)"D
} #c$z&J7e
y`\rb<AZ*t
gTb%c84
return n; .~,=?aq^
} -T2w?|
5pH6]$
u$<>8aMei
} ZVz`g]
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6PT"9vR`)
/* I~Q G
**SiteInfoBean.java <.=-9O6
*/ bKt4
package NetFox; nLY(%):(P
zALtG<_t
x7!gmbMfK'
public class SiteInfoBean { Ejj+%)n.
QxT\_Nej*n
oVQbc\P3
private String sSiteURL; //Site's URL >';UF;\5]Q
private String sFilePath; //Saved File's Path +1nzyD_E
private String sFileName; //Saved File's Name r2m&z%N&
private int nSplitter; //Count of Splited Downloading File a5?Yh<cJ
PZihC
]Jo}F@\g
public SiteInfoBean() -5Oy k,
{//nSplitter的缺省值为5 $]gflAe2
//default value of nSplitter is 5 {a0yHy$H
this("","","",5); Xi0fX$-,
} sAS[wcOQ
o>HU4O}
\V T.bUs
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) hA1p#
{ L&0aS:
sSiteURL= sURL; d:{}0hmxI
sFilePath = sPath; S]Ye`
sFileName = sName; Z8`Y}#Za[
this.nSplitter = nSpiltter; uM,R+)3
-z">ov-)
V1yP{XT=
} $|t={s34
hC?rHw H>
%Ix2NdC
public String getSSiteURL() EMzJyGt7
{ uC%mGZa
return sSiteURL; o37D~V;
} 0YAH[YF
dF><XZph
aKintb}n
public void setSSiteURL(String value) |nBs(>b
{ U|Uc|6
sSiteURL = value; XTRF IY
} 54#P
'Pxq>Os
CU:HTz=
public String getSFilePath() \027>~u {
{ JCci*F#r
return sFilePath; MzH'<`;BP
} MlR]+]
M(vX.kF
W;?e@}
public void setSFilePath(String value) OZEbs 7
{ intl?&wC
sFilePath = value; xlH3t&i7
} iK!FVKi}
VaA.J
3vdFO: j
public String getSFileName() 4v`G/w
{ -$$mrU
return sFileName; <H$!OPV
} LtUvFe
W#2} EX
"R"{xOQl
public void setSFileName(String value) @w;$M]o1
{ )iid9K<HB
sFileName = value; /D964VR1M\
} @9~x@[
[Sj"gLj
*4%%^*g.I
public int getNSplitter() A0OA7m:~4
{ Eihy|p
return nSplitter; "]|7%]
} 7Ah
p`EgMzVO,
xQl}~G]!
public void setNSplitter(int nCount) &G?"I%Vw
{ n6G&c4g<"
nSplitter = nCount; 2@IL n+#
} Ze <)B *
} 8Ltl32JSB[
Yr>0Qg],
\01kK)
/* &xZSM,
**Utility.java AD+OQLG]`
*/ &TL"Hd
package NetFox; J*38GX+
;NE4G;px4<
5A<}*T
public class Utility { ydA@@C\&
Uf MQ?(,
qoZ)"M
public Utility() ,.h@tN<C
{ EwmNgmYq
I9m9`4BK
}9glr]=
} jGT|Xo>t
OMM5ALc(F
//线程睡眠 5=I"bnIU
public static void sleep(int nSecond) bZr,jLEf
{ \hn$-'=4
try{ ^;F5ymb3U
Thread.sleep(nSecond); +25=u|#4r
} e-OKv#]
catch(Exception e) 1z0|uc
{ 8I Ip,#%v
e.printStackTrace (); OCq5}%yU&i
} Y]5spqG
} 5W$Jxuyqj
/Kq'3[d8
//日志 'Ebjn>"
public static void log(String sMsg) &=kb>*
{ }"SqB{5e(
System.err.println(sMsg); Gs,e8ri!
} ;)wk^W
e ;^}@X
GgnR*DVP$
public static void log(int sMsg) C|2|OTtQ
{ ~mwIr
System.err.println(sMsg); QPh3(K1w^
} UvM4-M%2JN
} \WbQS#Z9
bwcr/J(Nb
Fn iht<
/* AJE$Z0{q
**TestMethod.java w^("Pg`
*/ U=7nz|
package NetFox; J#ClQ%
qS"#jxc==+
]T)<@bmL
public class TestMethod { !dU$1:7
t%J1(H
}}ic{931
public TestMethod() 7!h> < sx
{ ///xx/weblogic60b2_win.exe IF-y/]
try{ Jz3,vVfQ:
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); -(>Ch>O
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ,,+4d :8$
SiteFileFetch fileFetch = new SiteFileFetch(bean); 8ICV"8(
fileFetch.start(); 6GPI gPL,
} 17,mqXX>
catch(Exception e){e.printStackTrace ();} +GL$[ 5G
SWY
RgL>0s
} + d3
pT3icy!A=
gu%i|-}
public static void main(String[] args) k3nvML,bv
{ .Gvk5Wn
new TestMethod(); , ,ng]&%i
} eV/oY1B]<
} Dte5g),R
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