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)); (A?>U_@
} YW7w>}aW
for(int i=0;i<nEndPos.length-1;i++) ;>7~@ K
{ HB )+.e
nEndPos = nStartPos[i+1]; "[ S[vkI
} x;W!sO@$
nEndPos[nEndPos.length-1] = nFileLength; qXtC7uNj$
} cpk\;1&t
} .gy:Pl]w
bVcJ/+Yx|
h?TIxo:6/
//启动子线程 807+|Ol[
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; I q|'#hs
for(int i=0;i<nStartPos.length;i++) ,9y6:W%5
{ b,Eq-Z;
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), zYM2`(Z 5B
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), qq!ZYWy2
nStartPos,nEndPos,i); wp~}1]g
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 4Y?fbb<
fileSplitterFetch.start(); &~eCDlX/
} [lIX&!T"
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), )y]Dmm
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); _!2lnJ4+5
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", |4DN2P
nEndPos = " + nFileLength); N@PuC>
// fileSplitterFetch[nPos.length-1].start(); ;\th.!'rn
.J-k^+-
1V`-D8-?
//等待子线程结束 mZU L}[xf
//int count = 0; 5"h4XINZ
//是否结束while循环 6KGT?d
boolean breakWhile = false; -|'@:cIZ
-Jd7
Z+V%~C1
while(!bStop) W)1nc"WqY
{ H^Pq[3NQ
write_nPos(); JX'}+.\
Utility.sleep(500); i3XtrP""
breakWhile = true; 0-PT%R
q2#Ebw%]
nOyG7:
for(int i=0;i<nStartPos.length;i++) JA{kifu0+
{ [`tOhL
if(!fileSplitterFetch.bDownOver) RV@B[:
{ :#vA5kC
breakWhile = false; 1o5kP,)
break; 0VvY(j:hp
} ~d&&\EZ
} &DGqY5=
if(breakWhile) G!`%.tH
break; zji9\
eLT3b6'"?
~V(>L=\V;
//count++; 8/2Wq~&
//if(count>4) UK OhsE
// siteStop(); F$>#P7ph\a
} .;31G0<w2
u"5/QB{
J4]"@0?6
System.err.println("文件下载结束！"); Hd4 ~v0eS
} iM!V4Wih6
catch(Exception e){e.printStackTrace ();} 7r,GdP.
} V@+sNM
jA8Bmwt;w
H`<u2fo|p
//获得文件长度 1<h@^s;
public long getFileSize() /7B3z}rd
{ R[F`b
int nFileLength = -1; &K!0yR
try{ _&(Wz0
URL url = new URL(siteInfoBean.getSSiteURL()); 8r}tf3xMCM
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); %^W(sB$b
httpConnection.setRequestProperty("User-Agent","NetFox"); \aSc2Ml]3n
6!)hl"
$ ^)g,
int responseCode=httpConnection.getResponseCode(); 0Runex[
if(responseCode>=400) atZNX1LD[/
{ h_X'O3r
processErrorCode(responseCode); ,6y.wNb:F
return -2; //-2 represent access is error FXk*zXn6
} v+EJ $
-DGuaUU
gs}&a3d7k
String sHeader; ?b d&Av
/slCK4vFc
H1~9f{
for(int i=1;;i++) DB"z93Mr<K
{ ,P`:`XQ>_B
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); [)}`w;#
//Utility.log(in.readLine()); UptKN|S&V
sHeader=httpConnection.getHeaderFieldKey(i); x15&U\U
if(sHeader!=null) eOVln1a
{ c&#Q`m
if(sHeader.equals("Content-Length")) GwgY{-|`
{ pb<eg,
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); Q_/UC#I8
break; Oc~<`C~
} ,X| >d
} kFQo[O]
else PtPx(R3
break; cooicKS7
} aa]|
} /"!ck2d&1
catch(IOException e){e.printStackTrace ();} WO69Wo\C
catch(Exception e){e.printStackTrace ();} M$v\7vBgO!
Ai%Wt-
FBi&MZ`
Utility.log(nFileLength); n%2c<@p#
*` -
q%s<y+
return nFileLength; t`6~ud>
} `j2|aX %Z*
`,FA3boE
(<`>B
//保存下载信息（文件指针位置） M;g"rpM
private void write_nPos() )fuAdG
{ }uD*\.
try{ ZDK+>^A)
output = new DataOutputStream(new FileOutputStream(tmpFile)); FKtCUq,:
output.writeInt(nStartPos.length); CW@EQ3y0
for(int i=0;i<nStartPos.length;i++) ;[C_ho
{ yqb$,$
// output.writeLong(nPos); c]ll89`||
output.writeLong(fileSplitterFetch.nStartPos); )WkN34Q
output.writeLong(fileSplitterFetch.nEndPos); .$&vSOgd(
} nFwg pT
output.close(); x'i~o'
} aE]RVyG@L
catch(IOException e){e.printStackTrace ();} t:'^pYN:g
catch(Exception e){e.printStackTrace ();} 'eQ*?a43
} ;x)f;!e+
9D5v0Qi
h^zcM_
//读取保存的下载信息（文件指针位置） )x,-O#"A
private void read_nPos() 5p.#nc!;y
{ lA,[&
try{ O2Y1D`&5
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); xs)SKG*
int nCount = input.readInt(); O8*yho
nStartPos = new long[nCount]; 1OFrxSg
nEndPos = new long[nCount]; z4[8*}
for(int i=0;i<nStartPos.length;i++) /GP:W6:6z6
{ LqQ&4I
nStartPos = input.readLong(); V'N]u(^
nEndPos = input.readLong(); \ 0F ey9c
} 3 lKBwjW
input.close(); CTB qX
} 30cb+)h(
catch(IOException e){e.printStackTrace ();} "f!H[F1~
catch(Exception e){e.printStackTrace ();} zM%2h:*+{
} EzU=q E
]D>\Z(b
pr\OjpvD
private void processErrorCode(int nErrorCode) 78'3&,+si
{ N,ihQB5
System.err.println("Error Code : " + nErrorCode); Xj6?,J
} s=&x%0f%
!M7727
Coe%R(x5
//停止文件下载 )k6z
public void siteStop() r[nvgzv@
{ O3L:v{Kn
bStop = true; ];{CNDAL2
for(int i=0;i<nStartPos.length;i++) K{G\=yJ((
fileSplitterFetch.splitterStop(); "V4ru&a
I(Q3YDdb
]EvK.ORy
} F$,i_7Z&6
} ibuoq X`
//负责部分文件的抓取 |HTTTz9R.
**FileSplitterFetch.java O=}jg0k
*/ C/z0/mk
package NetFox; KupQtT<
K"=I,Vr:
/n1H;~f]
import java.io.*; =.q8*7UY
import java.net.*; Hc-68]T
RZ9chTX/
\avgXndI
public class FileSplitterFetch extends Thread { 8Dc'"3+6
-H](2}
N9AM% H$7
String sURL; //File URL s+]6X*)
long nStartPos; //File Snippet Start Position HqKD]1
long nEndPos; //File Snippet End Position tc<HA7vpt~
int nThreadID; //Thread's ID )cRP6 =
boolean bDownOver = false; //Downing is over 1NU@k6UHl
boolean bStop = false; //Stop identical }ILg_>uq[
FileAccessI fileAccessI = null; //File Access interface $s9YU"
"xMnD(p
D]5cijO6
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException R|t.JoP9
{ #7,;/rtO7
this.sURL = sURL; 8CGjI?j
this.nStartPos = nStart; |D[4G6&
this.nEndPos = nEnd; iJEKLv
nThreadID = id; MryY<s
fileAccessI = new FileAccessI(sName,nStartPos);//定位 5tu 4uYp;
} Ov~>* [
)tR@\G>%
sy+tLDMd
public void run() %1PNP<3r0
{ :J;*]o:
while(nStartPos < nEndPos && !bStop) {$qLMx';
{ +m1y#|08
v^Pjvv=
LLW\1 cxi
try{ N:e5=;6s
URL url = new URL(sURL); 5|bc*iqU
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Q$=X ?{
httpConnection.setRequestProperty("User-Agent","NetFox"); H1kxY]_/
String sProperty = "bytes="+nStartPos+"-"; gK>aR ^*
httpConnection.setRequestProperty("RANGE",sProperty); T.#Vma
Utility.log(sProperty); L3^+`e
A{KF<Omu
i|OG#PsY-
InputStream input = httpConnection.getInputStream(); ~_hn{Ous
//logResponseHead(httpConnection); (GDW9:
H6%%n X
CUZ ;<Pn
byte[] b = new byte[1024]; \6c8Lqa
int nRead; i.6+CA
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ~{gV`nm=J
{ ^Y+P(o$HM
nStartPos += fileAccessI.write(b,0,nRead); vvcA-k?
//if(nThreadID == 1) zQyt1&!
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); T!Eyq,]
} "~ eF%}.
`\#J&N
!6:X]
Utility.log("Thread " + nThreadID + " is over!"); nkTu/)or
bDownOver = true; &! MV!9$
//nPos = fileAccessI.write (b,0,nRead); dhmZ3~cW>
} 5AO'IhpL
catch(Exception e){e.printStackTrace ();} n0%]dKCB
} pv;ZR
} ^+'\ u;\
>]S-a-|Bp
_ -C{:rV
//打印回应的头信息 Jde@Th
public void logResponseHead(HttpURLConnection con) K&>+<bJ_
{ jxNnrIA
for(int i=1;;i++) Avn)%9
{ <vUhJgN2/
String header=con.getHeaderFieldKey(i); q[MZSg
if(header!=null) tw%z!u[a
//responseHeaders.put(header,httpConnection.getHeaderField(header)); tg'2v/
Utility.log(header+" : "+con.getHeaderField(header)); `78)|a*R.
else )xj!7:n)
break; ]pP:
} UKBaGX:v
} &5o ln@YL
LyA}Nd]pyq
o!>h Q#h
public void splitterStop() Cp.qL
{ pLea 4
bStop = true; wwD?i.3
} P\2UIAPa\b
IIIP<nyc
2qxede
} {m7>9{`
pu?D^h9/
78-D/WY/X
/* 6y+}=)J
**FileAccess.java EQ>]~
*//文件访问(定位，写) eY#_!{*Wn
package NetFox; X6<%SJC
import java.io.*; (,!G$~Sy
vv5 uU8
}hyl)?*~
public class FileAccessI implements Serializable{ C)xM>M_CB
[/IN820t
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Nr#" 5<W
RandomAccessFile oSavedFile; 2E*h,Mo
long nPos; o+I'nFtnI
aokV'6
$K}Y
public FileAccessI() throws IOException ~s4o1^6L
{ J2d3&6
this("",0); T.x"a$AU
} W2W4w
.1#G*A|
Z%\*\6L)
public FileAccessI(String sName,long nPos) throws IOException -J\R}9 lIm
{ qVMBZ\`Qm
oSavedFile = new RandomAccessFile(sName,"rw"); 5 i;n:&Y
this.nPos = nPos; L>.*^]
oSavedFile.seek(nPos); *Y/}EX!F
} 7t~12m8x
LOf)D7T
W5_aS2$
public synchronized int write(byte[] b,int nStart,int nLen) VYC$Q;Z
{ @^UnrKSd
int n = -1; l11+sqg
try{ $>=?'wr
oSavedFile.write(b,nStart,nLen); CZ4Nw]dtR
n = nLen; fA{t\
} .tH[A[/1 a
catch(IOException e) .\:{6_
{ B(B77SOb
e.printStackTrace (); .qGfLvx%
} gOL-b9W
|QcE5UC
7;x}W-`iF
return n; %MH!L2|
} KKJ)BG?qZ
CE;J`;
CP"
} 5KIlU78
$2'Q'Mx[gd
q@0g KC&U
/* *j"u~ NF
**SiteInfoBean.java FQW{c3%qZ
*/ *p Q'w
package NetFox; Vnvfu!>(
vE<z0l
h}SP`
public class SiteInfoBean { 1Q>D^yPI[
|';oIYs|$
CS|al(?~
private String sSiteURL; //Site's URL %|\Af>o4d
private String sFilePath; //Saved File's Path |p\vH#6y+
private String sFileName; //Saved File's Name O\&-3#e
private int nSplitter; //Count of Splited Downloading File ' zz^!@
%Z]c[V.
Bt[Wh@
public SiteInfoBean() lJIcU RI4
{//nSplitter的缺省值为5 !Pf6UNN'
//default value of nSplitter is 5 `y0u(m5
this("","","",5); z8-dntkf
} NL}Q3Vv1.
}ofx?s}
L-z9n@=8\
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Gw1Rp
{ N&jHU+{OU
sSiteURL= sURL; :Cdqj0O3u
sFilePath = sPath; J*FUJT
sFileName = sName; EPu-oE=HW4
this.nSplitter = nSpiltter; y13Y,cz~B
5[5|_H+0
0LD$"0v/C3
} K2 b\9}
Uuq*;L
n3B#M}R
public String getSSiteURL() CD:$22*]
{ v{c,>]@
return sSiteURL; +]dh`8*8>1
} H&_drxUq;L
G%FLt[
S\"#E:A
public void setSSiteURL(String value) ]21`x
{ x*7Q
sSiteURL = value; @/f'i9?oM`
} s=[T,:Z
^sqTgrG
u}QcyG^
public String getSFilePath() U"L7G$
{ MR3\7D+9y
return sFilePath; *-\qO.4\
} 3$f+3/l
$rV4JROb
pr?k~Bn
public void setSFilePath(String value) nBkzNb{"AZ
{ rm?C_
sFilePath = value; T:=ST3#m
} =;A>1g$
oo-O>M#5
a>8&B
public String getSFileName() 6QM$aLLP?
{ K'\Jnn
return sFileName; R>T9 H0
} CAa&,ZR
PP&9ORG
[x8_ax}w
public void setSFileName(String value) 1G<S'd+N
{ Zgw4[GpL
sFileName = value; LTWiCI
} ^Gwpx+
&qyXi[vw
?"-1QG
public int getNSplitter() Ny` =]BA
{ C/#?S=w`4
return nSplitter; ;6}> Shs
} 1uco{JX<S
*)D$w_06S
2|\WaH9P
public void setNSplitter(int nCount) O<()T6
{ \&\U&^?
nSplitter = nCount; D5"Xjo*
} Y. Uca<{.[
} @p%WFNR0
4Is Wp!`W
9}A\BhtiM
/* l8H8c &
**Utility.java +%=lu14G
*/ MREB
package NetFox; >UnLq:G
XImX1GH
a^g}Z7D'T
public class Utility { Z9q1z~qSQ
ac%x\e$
LARMZoyi
public Utility() k@P?,r
{ LZ}m;
p\22_m_wd
5$&',v(
} utU;M*
5Zuk`%O
//线程睡眠 ^;'FC vd
public static void sleep(int nSecond) +FH@|~^O
{ V='A;gs
try{ #`@5`;U>#
Thread.sleep(nSecond); ov\+&=IRG
} ]ONBr(M\
catch(Exception e) F60?%gg
{ C;0VR
e.printStackTrace (); Hq aay
} Ij2Th]
} nhy:5eSK
#H;1)G(/
//日志 m+QZ|
public static void log(String sMsg) cJ#n<Rsz
{ *r)dtI*
System.err.println(sMsg); I{i6e'.jP
} }poLHS/
1vinO!
"Pl.G[Buc-
public static void log(int sMsg) U;#G$
{ ($Q|9>5,
System.err.println(sMsg); [&pMU)
} 1EWskmp
} #xh M&X
cb }OjM F
S;j"@'gz9
/* ;sAe#b
**TestMethod.java V3<#_:;
*/ ?{%"v\w
package NetFox; 9L>73P{_
.UYhj8
=g|5VXW5
public class TestMethod { !NMiWG4R
D< 0))r
VV"w{#XKw
public TestMethod() i,2eoM)FB
{ ///xx/weblogic60b2_win.exe 3LZvlcLb
try{ mhI
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); {7Hc00FM
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); <07]w$m/
SiteFileFetch fileFetch = new SiteFileFetch(bean); Mtc-
fileFetch.start(); 5DJ!:QY!
} vr4{|5M
catch(Exception e){e.printStackTrace ();} xAr&sGMA
oG\lejO
<B!DwMk;.
} NH4T*R)Vz
U6#9W}CE
%WPyc%I
public static void main(String[] args) ;Kh?iqn^
{ qfqL"G
new TestMethod(); n7.85p@ua
} vs@u*4.Ut<
} <8^ws90Y
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