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)); qg!|l7e
} ~j5x+yC
for(int i=0;i<nEndPos.length-1;i++) #iWSDy
{ }L3oR
nEndPos = nStartPos[i+1]; ]Nl=wZ#`
} f3{MvAy[
nEndPos[nEndPos.length-1] = nFileLength; :Jy'#c
} C] 9p5Hs
} U{z9>
*@Y3oh}S
7L@K _ZJ
//启动子线程 M^iU;vo
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ryCI>vJz
for(int i=0;i<nStartPos.length;i++) Y$Y_fjd_
{ &)vC;$vD`
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), I1\a[Xe8E
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), T ;vF(
nStartPos,nEndPos,i); GXjfQ~<]
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); C;`XlQG `
fileSplitterFetch.start(); Bj}^\Pc;}
} {>,V\J0p
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), !V\Q<So<
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); T G{k0cdOT
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", t{FlB!jv
nEndPos = " + nFileLength); 92d6U2T4&
// fileSplitterFetch[nPos.length-1].start(); 4Hn`'+b
)\be2^p
ks97k8B
//等待子线程结束 8<7GdCME
//int count = 0; YoLx>8
//是否结束while循环 D3^7y.u<)
boolean breakWhile = false; :l&V]}:7*
^#1.l=s
vab@-=%k
while(!bStop) tBT<EV{ G
{ C,NxE5?h
write_nPos(); w'fT=v)
Utility.sleep(500); DUe&r,(4O
breakWhile = true; E)7F\w
;3@YZM'wt
CQr<N w
for(int i=0;i<nStartPos.length;i++) $w0lrh[+
{ YJ/zU52JK~
if(!fileSplitterFetch.bDownOver) oY|,GvCnK
{ f7~9|w&
breakWhile = false; I,VH=Yn5,
break; 3a 1u
} 3g~^[&|i
} wTGbd
if(breakWhile) +1!qs,
break; V$icWu
D8nD/||;Z
qc!MG_{Y
//count++; ofMY,~w
//if(count>4) PN<C=gAe
// siteStop(); bb`':3%
} aKlUX
;?~$h-9)
1q3( @D5~+
System.err.println("文件下载结束！"); R:AA,^Z
} *"98L+
catch(Exception e){e.printStackTrace ();} >,gvb5
} b}wC|\s
k({\/t3i
3 M10fI?
//获得文件长度 8kt5KnD2
public long getFileSize() Q33"u/-v
{ %#Z/2<_
int nFileLength = -1; TO*BH^5R
try{ ^o@,3__7Q
URL url = new URL(siteInfoBean.getSSiteURL()); $DC*i-}qFg
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); iy\nio`
httpConnection.setRequestProperty("User-Agent","NetFox"); st&
3bd5FsI^pU
\U?n+6 7g
int responseCode=httpConnection.getResponseCode(); ^(f4*m6`
if(responseCode>=400) L0]_hxE?
{ tpEI(9>
processErrorCode(responseCode); 5P+t^\
return -2; //-2 represent access is error M9f?q.Bv
} !k(_PM
Enq|Y$qm
/?6|&
String sHeader; J5[~LZKW
{[t`j+J
:!f(F9
for(int i=1;;i++) qXW})(
{ J.+BD\pa
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); =GBI0&U
//Utility.log(in.readLine()); z6~ H:k1G%
sHeader=httpConnection.getHeaderFieldKey(i); *P!e:Tm)
if(sHeader!=null) 3!o4)yJWx
{ $RwB_F
if(sHeader.equals("Content-Length")) C4#rA.nF|
{ oM1 6C|
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); Ei3zBS?J)
break; ia{c
} NLe}Jqp
} %=<IGce
else q*AQq=
break; MfBdNdox7
} Y'3}G<'%
} asgF1?r
catch(IOException e){e.printStackTrace ();} ]G}B 0u3
catch(Exception e){e.printStackTrace ();} 's!-80sd
O:/yAc`
0l#)fJo
Utility.log(nFileLength); qxJQPz
9H]Lpi^OH
b2&V
return nFileLength; ;C/bJEgdd
} +~U=C9[gj
YEx)"t8E
"$5\,
//保存下载信息（文件指针位置） a!c[!
private void write_nPos() W~B5>;y
{ qy!Ou3^
try{ YIp-Y}6
output = new DataOutputStream(new FileOutputStream(tmpFile)); sK=}E=
output.writeInt(nStartPos.length); >7U>Yh
for(int i=0;i<nStartPos.length;i++) j#6|V]l
{ &MgeYpd
// output.writeLong(nPos); \hP=-J[~C
output.writeLong(fileSplitterFetch.nStartPos); yWHiw<
output.writeLong(fileSplitterFetch.nEndPos); Zx?b<"k
} 6ZqgY1
output.close(); kDYN>``biP
} W;Jx<-#1
catch(IOException e){e.printStackTrace ();} ,rwuy[Q8
catch(Exception e){e.printStackTrace ();} w[Ep*-yeI
} xq-$\#O
=]Hs|{
$ Cjk
//读取保存的下载信息（文件指针位置） 3Gr&p6
private void read_nPos() AdoZs8Q
{ w,jcm;
try{ {sv{847V
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); rp:wQH7
int nCount = input.readInt(); F X1ZG!
nStartPos = new long[nCount]; f|aDTWF
nEndPos = new long[nCount]; Y"eEkT\
for(int i=0;i<nStartPos.length;i++) ]yX@'f
{ QI!i
nStartPos = input.readLong(); fd8#Ng"1
nEndPos = input.readLong(); %xyX8c{sP
} -#A:`/22
input.close(); c;I, O
} +MO E
catch(IOException e){e.printStackTrace ();} gKb0)4 AK
catch(Exception e){e.printStackTrace ();} 88a<{5 :z
} ~%|G+m>
xQlT%X;'
lg:y|@Y''
private void processErrorCode(int nErrorCode) ;? uC=o>Z{
{ dyFKxn`,
System.err.println("Error Code : " + nErrorCode); qG>DTKIU
} ; a/cty0Ch
jlKGXD)Q[
fjDpwb:x)
//停止文件下载 oBlzHBn>0
public void siteStop() 8!h'j
{ 26:evid
bStop = true; 5>ST"l_ca
for(int i=0;i<nStartPos.length;i++) Ew^ @Aq
fileSplitterFetch.splitterStop(); dNVv4{S
dTD5(}+J
o;-<|W>
} G\Q9IcJ0dY
} D)&o8D`
//负责部分文件的抓取 eZO9GMO
**FileSplitterFetch.java s5Fr)q// !
*/ D?+ RJs
package NetFox; >4![&&
~%q7Vmk9
|r~ uos
import java.io.*; j+748QAhh
import java.net.*; bGh0<r7R
%7`d/dgR
j=.g:&r)
public class FileSplitterFetch extends Thread { iWXMKu
v`G U09
#cEq_[yI
String sURL; //File URL "L~@.W!@
long nStartPos; //File Snippet Start Position ^[M~K5Y
long nEndPos; //File Snippet End Position x|apQ6
int nThreadID; //Thread's ID 3GmK3uM
boolean bDownOver = false; //Downing is over }?O[N}>,m
boolean bStop = false; //Stop identical Yn[x #DS
FileAccessI fileAccessI = null; //File Access interface Jc~E"x
J7a-CI_Tf
TJ2/?p\x
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException )Ul&1UYA
{ yer> x
this.sURL = sURL; ,eELRzjl
this.nStartPos = nStart; uU+s!C9r
this.nEndPos = nEnd; O=O(3Pf>
nThreadID = id; -"Gl 4)
fileAccessI = new FileAccessI(sName,nStartPos);//定位 Rx. rj~
} tmxPOe
BpXEK.Xw
HRRngk#lV
public void run() S.fXHtSx
{ ti;%BS
while(nStartPos < nEndPos && !bStop) _XN~@5elrC
{ F|]rA*2u
+IsWI;lp
>1XL;)IL>
try{ dx359
URL url = new URL(sURL); x9*ys;~w
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); g@(30{
httpConnection.setRequestProperty("User-Agent","NetFox"); mahi7eU P
String sProperty = "bytes="+nStartPos+"-"; m0iV m|
httpConnection.setRequestProperty("RANGE",sProperty); x[m'FsR4
Utility.log(sProperty); T^.{9F]*S
$wXih#7
rAatJc"0
InputStream input = httpConnection.getInputStream(); S1>Z6
//logResponseHead(httpConnection); WRMz]|+}4
WB"$u2{|i
0O['w<_
byte[] b = new byte[1024]; j[T%'%
int nRead; er\:U0fr#@
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) V9$-twhu
{ :A$wX$H01
nStartPos += fileAccessI.write(b,0,nRead); M7H~;S\3IM
//if(nThreadID == 1) xucIjPi]
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 7+]F^ 6
} B=x~L
2vXGO|W
uk{J@&F
Utility.log("Thread " + nThreadID + " is over!"); y%g`FC
bDownOver = true; ;G$)MS'nB
//nPos = fileAccessI.write (b,0,nRead); Y=WR6!{
} gx&73f<J
catch(Exception e){e.printStackTrace ();} i~AJ.@ #
} AuM:2N2
} I_L;T
'qlxAYw<f
G\IocZ3Gz
//打印回应的头信息 EreAn
public void logResponseHead(HttpURLConnection con) r2)pAiTM*
{ bn|DRy
for(int i=1;;i++) A@{ !:_55
{ ][N) 2_^M
String header=con.getHeaderFieldKey(i); /op/g]O}
if(header!=null) 9e76pP(
//responseHeaders.put(header,httpConnection.getHeaderField(header)); $@4e(Zrmo
Utility.log(header+" : "+con.getHeaderField(header)); 8I {56$
else 9w$7VW;
break; Ty iU1,oO
} [EcV\.
} 4}PeP^pj
6A@Lj*:2m
VG#$fRrZ
public void splitterStop() 0<"tl0p_
{ :=B[yD!
bStop = true; nR#a)et
} OUKj@~T
E-[:. &
|3W3+Rn!
} 7vdHR\#;$
qFGB'mIrFz
.k|-Ks|d|
/* ^K*~ <O-
**FileAccess.java )[RpZpd`*
*//文件访问(定位，写) D)RdOldr
package NetFox; >R) F}
import java.io.*; f@#w{W,3
l+'`BBh*]
@<%oIE~]F
public class FileAccessI implements Serializable{ 3Y=,r!F.h
(#lm#?<)
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 )<tzm'Rc
RandomAccessFile oSavedFile; 8:BQHYeJK
long nPos; oO}>i0ax*
X$ejy/+.
s:G[Em1
public FileAccessI() throws IOException gx&\Kw6HM
{ N_*u5mfQX
this("",0); TosPk(o(
} tgS+"ugl
_;%.1H{N
<m:4g ,6
public FileAccessI(String sName,long nPos) throws IOException C!oksI
{ RbyF#[}
oSavedFile = new RandomAccessFile(sName,"rw"); 939]8BERt
this.nPos = nPos; Ig='a"%
oSavedFile.seek(nPos); hu`Lv
} CD$u=E ]
'XG:1Bpm
h7)VJY
public synchronized int write(byte[] b,int nStart,int nLen) 6Eij>{v
{ FDZeIj9uF
int n = -1; 1'gKZB)TG7
try{ /,-h%gj
oSavedFile.write(b,nStart,nLen); knI*-
n = nLen; @DUN;L 4
} QGu7D #%|
catch(IOException e) n^3NA|A
{ | 3hT{
e.printStackTrace (); nA|gQibA
} kwDjK"
1NB2y[
n+:m_2T
return n; $ $W{HsX
} :H~UyrN
5n-9#J$
R*zBnHAb!
} @|jKO5Y
ze-TBh/
JsHxQ0Tw
/* %D`^
**SiteInfoBean.java ktkn2Twa/
*/ RcKQER
package NetFox; m&(%&}g
f/$-Nl.
Ki&WS<,0Z
public class SiteInfoBean { `bBfNI?3d*
..v@Q%
Xq} n^W
private String sSiteURL; //Site's URL Qq@_Z=mt
private String sFilePath; //Saved File's Path tRpL0 =y
private String sFileName; //Saved File's Name .`i'gPLkn2
private int nSplitter; //Count of Splited Downloading File 7<Z~\3x
g]oc(RM
$X{B* WF
public SiteInfoBean() ?HEo9/ *7
{//nSplitter的缺省值为5 '2Mjz6mBDA
//default value of nSplitter is 5 #3 }5cC8_
this("","","",5); ir( -$*J
} .YnP%X=
~5XL@jI^
_#y(w%
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) L<{OBuR
{ P'FPe55F
sSiteURL= sURL; ;p?42rCIcl
sFilePath = sPath; BWqik_
sFileName = sName; [MSDk"o&
this.nSplitter = nSpiltter; ZEXj|wC
*Xf[b)FR
QSl:=Q'
} _>Pe]3
c,{&
sM);gI14
public String getSSiteURL() 3> n2
{ DkF@XK0c3
return sSiteURL; cP$wI;P
} +S:u[x
dvrvpDoE.
5Xq.=/eX
public void setSSiteURL(String value) 8k*
{ hSLwiX~
sSiteURL = value; 9~Y)wz
} '>S8t/
` maN5)
Y3sNr)qss
public String getSFilePath() 945 |MQPn
{ 8as$h*Wh
return sFilePath; JaB tX'
} jN5} 2 p*
;OT#V,}r
2:6Y83
public void setSFilePath(String value) _dJVnC1 !
{ o0-fUCmC
sFilePath = value; t2!$IHE:
} ,/[dmoe
/o}0oo5B
ozxK?AMgG
public String getSFileName() b'Piymx
{ -?2&5YB
return sFileName; X,C/x)
} nJM9c[Ou^H
y<Z#my$`|n
(dGM;Dq8
public void setSFileName(String value) OJC*|kN-#^
{ E-7a`S
sFileName = value; D,m&^P=%e
} X<@y*?D9D
ki][qvXJ
>8Yrmq
public int getNSplitter() jP6oJcZ
{ GmEJ,%A
return nSplitter; k:HSB</}
} ys"mP*wD
\8@[bpI@g
h#6 jUQ
public void setNSplitter(int nCount) NIXcib"tG
{ n<Xm%KH.
nSplitter = nCount; ]J"+VZ_"I
} ZF11v(n
} #k|g9`
}IalgQ(i
_UVX
/* | xErA
**Utility.java C\hZ;Z1
*/ k0Vo
package NetFox; vSHIl"h
"n2xn%t{
?#{2?%_
public class Utility { T\$^>@
WriJco<v
N6m*xxI{
public Utility() ( _F
{ xZ{|D
{0Ol/N;|D
~%!U,)-
} GXvo't@N
I!i#=
//线程睡眠 `sp'Cl!
public static void sleep(int nSecond) ,h)T(
{ rc{[\1 -N
try{ l4BO@
Thread.sleep(nSecond); 5fDtSsW
} 5l7L@Ey
catch(Exception e) HDae_.
{ .WPR}v,.Z
e.printStackTrace (); ]&tr\-3
} kl{OO%jZ
} vS,G<V3B
v%PWr5]
//日志 ^zluO
public static void log(String sMsg) fKK-c9F
{ Xe^=(| M
System.err.println(sMsg); A%2M]];%X
} JI#Enh!Lv
L|xen*O
&.bR1wX
public static void log(int sMsg) *U^\Mwp
{ zZjLt1
System.err.println(sMsg); u g$\&rM>
} Z=5}17kA
} YPJx/@Z`
sZP3xh[B
hZ/
/* `F`'b)
**TestMethod.java Vh[o[ U
*/ -D^y)
package NetFox; sN`o_q{Q
`/j|Rb|eow
M$hw(fC|m1
public class TestMethod { ..]X<
M[3w EX^
D"XQ!1B%
public TestMethod() ?%fZvpn-
{ ///xx/weblogic60b2_win.exe ~^5n$jq
try{ 9QQ@Y}
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); CR PE?CRQF
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ALieUf
SiteFileFetch fileFetch = new SiteFileFetch(bean); WHj4#v(
fileFetch.start(); C-b%PgA
} $j2)_(<A%Q
catch(Exception e){e.printStackTrace ();} +mW$D@Pf
#=~1hk
N~<}\0
} la{:RlW
oZcwbo8
d`][1rZk
public static void main(String[] args) &Or=_5Y`
{ )tQ6rd'
new TestMethod(); U.sPFt
} T9v#Jb6
} !U~#H_
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