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)); VX]Ud\(
} -E>LB\[t)
for(int i=0;i<nEndPos.length-1;i++) _<6B.{$\7m
{ `=19iAp.
nEndPos = nStartPos[i+1]; zr^"zcfz&
} E?cf#;2h8m
nEndPos[nEndPos.length-1] = nFileLength; Bz4;R9_%I
} ;(Kj-,>
} rB}2F*eT
^C70b)68
8&c:73=?X
//启动子线程 R7 ^f|/l
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; u -A_l<K
for(int i=0;i<nStartPos.length;i++) wrAcVR
{ bD<hzOa
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), H-jxH,mJmW
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), (Ky$(Ubb#6
nStartPos,nEndPos,i); ,)Z1&J?
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); *Z2#U?_
fileSplitterFetch.start(); +XpQ9Cd
} \vF*n Z5/
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), aqKrf(Rv
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); )W |_f
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", _FP'SVa}D
nEndPos = " + nFileLength); Eu`K2_b
// fileSplitterFetch[nPos.length-1].start(); p61F@=EL
@f`s%o
iG+=whvL
//等待子线程结束 ChRCsu~
//int count = 0; O~D]C
//是否结束while循环 grTwo
boolean breakWhile = false; !]l;n Fd
g4}K6)@
Nc:0opPM
while(!bStop) :aWC6"ik-W
{ $\q}A:
write_nPos(); l,:>B-FV
Utility.sleep(500); 5~{s-Ms
breakWhile = true; *_/n$& I%&
F~wqt7*
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for(int i=0;i<nStartPos.length;i++) $aDkZj
{ y4Lh:;
if(!fileSplitterFetch.bDownOver) tG*HUN?*
{ bj7r"_
breakWhile = false; 1R"Z+tNB
break; g96]>]A<{
} F&$~]R=&
} /TY=ig1z
if(breakWhile) ~qkn1N%'
break; DvY)n<U1qA
>(C5&3^
v%;Nyab6$
//count++; f J+
//if(count>4) (x140_TH~
// siteStop(); wG X\ub#!
} Bj* M W
|Fe*t
:&BE-f
System.err.println("文件下载结束！"); F5%IsAH
} mO&zE;/[
catch(Exception e){e.printStackTrace ();} n7pjj
} ]:.9:RmEV
cHX~-:KOr
0`Y"xN`'i
//获得文件长度 Ti&v9re%wO
public long getFileSize() V?-SvQIk1
{ _bSn YhS
int nFileLength = -1; nHl{'|~
try{ J=Hyoz+9
URL url = new URL(siteInfoBean.getSSiteURL()); ^b6yN\,S
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); *}=z^;_oq
httpConnection.setRequestProperty("User-Agent","NetFox"); !'*1;OQ
3Uy(d,N
`gz/?q
int responseCode=httpConnection.getResponseCode(); _:+ k|I
if(responseCode>=400) lf}%^od~6
{ %a|m[6+O
processErrorCode(responseCode); i Ie{L-Na
return -2; //-2 represent access is error "z4V@gk
} Eg4_kp0Lq
}ZJ*N Y
G3j'A{
String sHeader; VvTi>2(.
='Yg^:n
K(rWM>Jv
for(int i=1;;i++) '1rO&F
{ XPT@ LM
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); m.ejGm?
//Utility.log(in.readLine()); =DwY-Ex
sHeader=httpConnection.getHeaderFieldKey(i); Lc_cB`
if(sHeader!=null) );d"gv(]D
{ 4rUOk"li
if(sHeader.equals("Content-Length")) ,P^4??' o
{ r>g5_"FL
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); U U@
break; b)7v-1N
} UnOcw
} K[l5=)G0L
else MY l9 &8
break; +^ `n- m
} N1Dr'aw*
} ;nAI;Qw L
catch(IOException e){e.printStackTrace ();} 4P^CqD&i
catch(Exception e){e.printStackTrace ();} v0KJKrliGO
k1~? }+<e
="de+S8W
Utility.log(nFileLength); >*WT[UU
Z+2 j(
1!Afq}|
return nFileLength; "mc ]^O
} Or:P*l
mq+<2 S
]MnQ3bWq"j
//保存下载信息（文件指针位置） @|<qTci
private void write_nPos() _&aPF/
{ h6Cqc}P
try{ uLSuY}K0
output = new DataOutputStream(new FileOutputStream(tmpFile)); Y=Om0=v
output.writeInt(nStartPos.length); WkDXWv\{,{
for(int i=0;i<nStartPos.length;i++) W^)'rH
{ <aQ5chf7
// output.writeLong(nPos); O3tw@ &k
output.writeLong(fileSplitterFetch.nStartPos); id[caP=`
output.writeLong(fileSplitterFetch.nEndPos); d[oHjWk
} f7:}t+d
output.close(); pyp0SGCM:
} q_Z6s5O
catch(IOException e){e.printStackTrace ();} #,9#x]U#v
catch(Exception e){e.printStackTrace ();} qm< mw"]
} xM![
6 tl#AJ-
W~/{ct$Y
//读取保存的下载信息（文件指针位置） k,-0OoCL-!
private void read_nPos() Zu/w>
{ qO[_8's8
try{ r0q?e`nsA
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); OM81$Xo=
int nCount = input.readInt(); iH8V]%
nStartPos = new long[nCount]; RaOLy \
nEndPos = new long[nCount]; ~L:H]_8F l
for(int i=0;i<nStartPos.length;i++) wY"BPl]b
{ Y6m:d&p=}
nStartPos = input.readLong(); 8wMwS6s:
nEndPos = input.readLong(); <YvW /x
} a"^rOiXR{
input.close(); wY3|5kbDj
} eu'S~c-l
catch(IOException e){e.printStackTrace ();} h}Lrpr2r
catch(Exception e){e.printStackTrace ();} GK1oS
} S=G2%u!;
[F 24xC+
h_6c9VI
private void processErrorCode(int nErrorCode) i?f;C_w
{ !V-(K_\t
System.err.println("Error Code : " + nErrorCode); >Q:h0b_$U
} K9ek
@a,}k<@E
1NkJs&
//停止文件下载 dUv(Pu(.#
public void siteStop() 6pbtE]
{ 9ePom'1f1
bStop = true; \LM.>vJ
for(int i=0;i<nStartPos.length;i++) >L433qR
fileSplitterFetch.splitterStop(); ~.CmiG.7
N v6=[_D
qWD(rq+9
} O bc>f|l]
} u}89v1._Jn
//负责部分文件的抓取 b-RuUfUn0
**FileSplitterFetch.java Uh+6fE]p
*/ ]q/USVj{
package NetFox; k:URP`w[X=
(*9-Fa
3~?m?vj|Y
import java.io.*; n?"("Fiw
import java.net.*; *t_Q5&3L+U
pA6A*~QE
QW_BT^d"
public class FileSplitterFetch extends Thread { 49YN@PXC
$e:bDZ(hjj
#I\" 'n5M
String sURL; //File URL V3ExS1fNf
long nStartPos; //File Snippet Start Position <==6fc>s
long nEndPos; //File Snippet End Position Cv[1HO<
int nThreadID; //Thread's ID nPk&/H%5hn
boolean bDownOver = false; //Downing is over +'wO:E1( w
boolean bStop = false; //Stop identical `><E J'h
FileAccessI fileAccessI = null; //File Access interface &0]5zQ
vRH2[{KQ9
bnJ4Edy
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException L%+mD$@u
{ G&08Qb ,N
this.sURL = sURL; $laUkD#vz
this.nStartPos = nStart; #7@p
this.nEndPos = nEnd; [S9"' ^H
nThreadID = id; BZ(I]:oDL
fileAccessI = new FileAccessI(sName,nStartPos);//定位 1x8wQ/p|
} b@O{eQB
H4$f+
tG~[E,/`
public void run() #Hy\lJ
{ <h~=d("j
while(nStartPos < nEndPos && !bStop) MaPI<kYQv
{ -A zOujSS
UG[r /w5(F
v-wZHkdd1
try{ GJF &id
URL url = new URL(sURL); MjWxfW/
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); mF4y0r0
httpConnection.setRequestProperty("User-Agent","NetFox"); .A0fI";Q
String sProperty = "bytes="+nStartPos+"-"; )S;3WnQ)
httpConnection.setRequestProperty("RANGE",sProperty); txE+A/>i9
Utility.log(sProperty); :(@P *"j
)_Z^oH ]<
Jt0U`_
InputStream input = httpConnection.getInputStream(); o#=C[d5BV
//logResponseHead(httpConnection); XlnSh<e
]B$J8.{q0
a ,"
byte[] b = new byte[1024]; RhC|x,E
int nRead; `3`.usw
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 7C R6ew~
{ 1jO%\uR/
nStartPos += fileAccessI.write(b,0,nRead); ?a)Fm8Y
//if(nThreadID == 1) 0Ua=&;/2
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); }9&dY!h +
} nxNHf3
;e< TEs
%NM={X|'
Utility.log("Thread " + nThreadID + " is over!"); ci/qm\JI<<
bDownOver = true; D$@2H>.-
//nPos = fileAccessI.write (b,0,nRead); 3_`)QYU'
} \0vs93>?
catch(Exception e){e.printStackTrace ();} jAU&h@
} hRMya#%-
} (4Nj3x o
{e q378d
CD%Cb53
//打印回应的头信息 XMdCQ=
public void logResponseHead(HttpURLConnection con) .rS. >d^n
{ dMCoN8W
for(int i=1;;i++) bwj{5-FU
{ (.X)=
String header=con.getHeaderFieldKey(i); 1b86@f
if(header!=null) jsx&h Y%(
//responseHeaders.put(header,httpConnection.getHeaderField(header)); crN*eFeW
Utility.log(header+" : "+con.getHeaderField(header)); klH?!r&
else K:GEC-
break; E@yo/S
} j=Izwt>
} :Zx|=
bE{YK
T]nAz<l),
public void splitterStop() >239SyC-,
{ boHbiE
bStop = true; fx>U2
} oOC&w0
x/wgD'?
lfre-pS+
} 3zu6#3^
*ra>Kl0
Ga-cto1Y
/* cpALs1j:
**FileAccess.java ch25A<O<R.
*//文件访问(定位，写) #9Ect@?N0
package NetFox; V1pBKr)v
import java.io.*; `*BV@
6q>}M
+cSc0:
public class FileAccessI implements Serializable{ {dm>]@"S
~KYzEqy
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 ' QMcQvU
RandomAccessFile oSavedFile; u&^KrOM@#
long nPos; GM?s8yZ<
nj1o!+9>$
YB<nz<;JR
public FileAccessI() throws IOException jT}={[9b
{ MtaGv#mJ
this("",0); ^m&I^\
} C=]<R<Xy
MkL2I+*
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public FileAccessI(String sName,long nPos) throws IOException 9}m?E<6&
{ GBT|1c'i
oSavedFile = new RandomAccessFile(sName,"rw"); GqR|hg
this.nPos = nPos; sZT~5c8
oSavedFile.seek(nPos); ^D6TeH
} goA=U
elQjPvb
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public synchronized int write(byte[] b,int nStart,int nLen) *OznZIn
{ BAY e:0
int n = -1; I`H&b& .`
try{ 8V 4e\q
oSavedFile.write(b,nStart,nLen); xPPA8~Dm*
n = nLen; Y0T:%
} af %w|M
catch(IOException e) AU}kIm_+
{ Nw$OJ9$L>
e.printStackTrace (); IGQBTdPUa
} At?|[%<`
Q?1J<(oq9
{59>U~
return n; 7C0xKF
} !%ju.Xs8
E;{RNf|
m*A b<$y
} GWWg3z.o"W
f? @Qt<+k
\)rMC]
/* jwa6`u
**SiteInfoBean.java s_XCKhN:
*/ `Wg"m~l$N
package NetFox; B=L!WGl<!
( _6j@?u
GDSXBa*7
public class SiteInfoBean { +pwTM]bV
H-+U^@w
fmj}NV&ma
private String sSiteURL; //Site's URL n qO*z<
private String sFilePath; //Saved File's Path G)%V 3h
private String sFileName; //Saved File's Name Um{) ?1
private int nSplitter; //Count of Splited Downloading File 3qf#NJN}
I9qFXvqL
-^2p@^
public SiteInfoBean() 3*~`z9-z
{//nSplitter的缺省值为5 SsTBjIX
//default value of nSplitter is 5 6qFzo1LO
this("","","",5); uX3yq<lK"
} vJ}WNvncVF
qnboXGaFu
RQ=$, i`
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) zKGZg>q
{ yuBRYy#E|%
sSiteURL= sURL; F:T(-,
sFilePath = sPath; } &+]UGv
sFileName = sName; V 97ORI
this.nSplitter = nSpiltter; Mf#@8"l
1F,U^O
oo\^}jb
} %%}l[W
AXHY$f|
BInSS*L
public String getSSiteURL() Lv['/!DJ|
{ dN3^PK
return sSiteURL; RU7+$Z0K
} q"<=^vi
t3Gy *B
Os-Z_zSl6
public void setSSiteURL(String value) 9dNkKMc@
{ SNOc1c<~
sSiteURL = value; rIPfO'T?
} +;lDU}$
A{T9-f@X
E> GmFw
public String getSFilePath() <b,WxR`
{ 2PyuM=(Wt
return sFilePath; 4"kc(J`c
} t2)uJN`a$X
f?tU5EX
Q4-d|
public void setSFilePath(String value) 7FcZxu\
{ ]pBEoktp
sFilePath = value; z2YYxJc&w
} 9DhM 9VU
ygnZ9ikh<-
hRX9Du`$
public String getSFileName() =Pw{1m|k
{ $I*}AUp v?
return sFileName; #X'-/q`.
} YGOkqI
W7WHDL^
\99'#]\_/E
public void setSFileName(String value) !7I07~&1
{ "[~yu* S
sFileName = value; ]sb?lAxh{
} 36(qe"s
8iaMr278W
&?bsBqpN
public int getNSplitter() ~/K&=xE
{ NzyEsZ]$
return nSplitter; ai$l7]7
} pP":,8Q{
^g6v#]&WA
aSIb0`(3
public void setNSplitter(int nCount) hbJy<e1W
{ =t-Ud^3
nSplitter = nCount; !9 kNL
} |OF3O,5z
} vw!7f|Pg ~
"KK}}$>
,H"}Rw
/* S;#:~?dU
**Utility.java a%m )8N;C
*/ 5*Zz_ .
package NetFox; ^2$b8]q
)yb~ kbe
d^RcJ3w
public class Utility { 9_5>MmiB
6jc5B#
b}Gm{;s!
public Utility() L]z8'n,
{ 1$E[`` n
/]z#V'
Fz(;Eo3
} 153*b^iDBh
18%$Z$K,
//线程睡眠 A,EG0yb
public static void sleep(int nSecond) 8Gy]nD
{ 2EpQ(G J
try{ vzI>:Bf
Thread.sleep(nSecond); i=n;rT
} liPrxuP`
catch(Exception e) L@[}sMdq(
{ A}9^,C$#
e.printStackTrace (); 3l~7
} 1YMi4.
} n]#YL4j
!O!:=wq
//日志 paV1o>_Rd
public static void log(String sMsg) b*h:e.q
{ o'$-
System.err.println(sMsg); 2(GYk
} i`l;k~rP
- i2^ eZl
.$cX:"_Mk
public static void log(int sMsg) XkqsL0\
{ "6%{#TZ
System.err.println(sMsg); wS|k3^OV%
} ',[AKXJ
} h& 4#5{=
ZKt{3P
'j'6x'[>]
/* THOYx :Nr;
**TestMethod.java uaP5(hUI
*/ nX7F<k4G2
package NetFox; -2}ons(
y{(Dv}
j07A>G-=
public class TestMethod { Cd^1E]O0{
!U4YA1>>
g/$RuT2U
public TestMethod() qmnl
{ ///xx/weblogic60b2_win.exe 8SroA$^n
try{ "kcix!}&
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); [Y`E"1f2
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 6W YVHG
SiteFileFetch fileFetch = new SiteFileFetch(bean); Z"Lr5'}
fileFetch.start(); 4s|qxCks
} \anOOn@
catch(Exception e){e.printStackTrace ();} 3%9XJ]Qao
`*Wg&u
RRyD<7s1
} mnZfk
VgbT/v
GBS+ 4xL|
public static void main(String[] args) 7R5ebMW V
{ *\:sHVyG(
new TestMethod(); GE] QRKf
} -XnIDXM
} &$T7eOiZ
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