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)); g7.7E6%H
} =n> iQS
for(int i=0;i<nEndPos.length-1;i++) =AWX +znP
{ H0: iYHu
nEndPos = nStartPos[i+1]; np<f,
} [Bl $IfU
nEndPos[nEndPos.length-1] = nFileLength; E~'q?LJOB
} 6\; 4 4,3
} ;M%oQ>].[
u)<Ysx8G
<9Lv4`]GU5
//启动子线程 .}IK}A/-
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; pem3G5 `g=
for(int i=0;i<nStartPos.length;i++) `,F&y{A
{ Q%M'[L?[
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), +")qi=
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), {DKXn`V
nStartPos,nEndPos,i); <C7M";54-
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); FY1},sq
fileSplitterFetch.start(); ioE66-n
} +)/Rql(lY
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 08TaFzP81
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); !!?+M @
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", Y|{r vBKjf
nEndPos = " + nFileLength); -ET*M<
// fileSplitterFetch[nPos.length-1].start(); $=e&q
u=p ;A1oy
]_^"|RJ
//等待子线程结束 \_m\U.*
//int count = 0; .V5q$5j
//是否结束while循环 ib5;f0Qa
boolean breakWhile = false; oV0LJ%
+-Z"H)
OaD Alrm
while(!bStop) #6Efev
{ _n-VgPRn
write_nPos(); 3q~":bpAp
Utility.sleep(500); P!`Q_h6a
breakWhile = true; 37j\D1Y
eT7!a']x
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for(int i=0;i<nStartPos.length;i++) F&W0DaH
{ .ujs`9d_-
if(!fileSplitterFetch.bDownOver) \_*?R,$3Y,
{ /3CHE8nSh
breakWhile = false; 4kW30Ma
break; wx]+*Lzz
} 8ktjDs$=.:
} A}>|tm7|
if(breakWhile) )64LKb$
break; HGP%a1RF#
kPx]u\
@+0@BO12
//count++; fZka%[B
//if(count>4) Wo:zU
// siteStop(); otmIu`h
} b xk'a,!S
^@|<'g.R-
>< <$
System.err.println("文件下载结束！"); <GL}1W"Ay
} ^%K1R;
catch(Exception e){e.printStackTrace ();} ;,F-6RNj
} 8]cv&d1f
tJ?qcT?
d&PE,$XC
//获得文件长度 ImUQ*0
public long getFileSize() "4Vi=*2V
{ p6&LZ=tL3
int nFileLength = -1; hYP6z^
try{ SeRK7Q&_
URL url = new URL(siteInfoBean.getSSiteURL()); ,_"7|z wb
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ~6@c]:
httpConnection.setRequestProperty("User-Agent","NetFox"); D-TNFYYy2
1=9qAp;?o
r+{!@`dYi
int responseCode=httpConnection.getResponseCode(); #hy5c,}>
if(responseCode>=400) ugIm:bg&
{ 38x[Ad4%
processErrorCode(responseCode); ^D]7pe
return -2; //-2 represent access is error 9[t]]
} ({d,oU$>y
dvg;
x*loACee.
String sHeader; GsP@ B'
OBKC$e6I
vxbH^b
for(int i=1;;i++) }<5\O*kX4
{ b:}wR*Adc
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); bik] JIM
//Utility.log(in.readLine()); dUsJv
sHeader=httpConnection.getHeaderFieldKey(i); /?.r!Cp
if(sHeader!=null) 2-"Lxe65f
{ |!4BWt
if(sHeader.equals("Content-Length")) G<">/_jn
{ z{D$~ ob
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); G:h;C].
break; ~# hE&nq
} )E[ Q
} M\Uc;:) H
else 2HvTM8
break; +H)!uLvaB
} ~n8Oyr
} :w {M6mM>
catch(IOException e){e.printStackTrace ();} {|Mxvp*Hg
catch(Exception e){e.printStackTrace ();} xoz*UA.
8^P2GG'+-
323yAF
Utility.log(nFileLength); =#POMK".6
((RpT0rP\
xVHQ[I%
return nFileLength; fJF8/IQ4
} V\k5h
Pjj;.c 7_j
OVQxZ~uQ
//保存下载信息（文件指针位置） 26('V `N
private void write_nPos() ,{`o/F/
{ t(z(-G|&
try{ cjy0s+>>
output = new DataOutputStream(new FileOutputStream(tmpFile)); bbQ10H
output.writeInt(nStartPos.length); Sq?6R}q%
for(int i=0;i<nStartPos.length;i++) >n$EeJ
{ IxEQh)J X
// output.writeLong(nPos); ?v)"%.
output.writeLong(fileSplitterFetch.nStartPos); $X.'W\o|
output.writeLong(fileSplitterFetch.nEndPos); hIzPy3
} %~B)~|h
output.close(); \0*yxSg,^
} QRg"/62WCD
catch(IOException e){e.printStackTrace ();} /\3XARt
catch(Exception e){e.printStackTrace ();} `F-Dd4B
} \K_!d]I {
T,xVQ4J?
fr,CH{Uq
//读取保存的下载信息（文件指针位置） VxPTh\O*[
private void read_nPos() Y00i{/a 8
{ bAy5/G!_R
try{ ?VOs:sln
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); nI|Lx`*v
int nCount = input.readInt(); =AnZ>6
nStartPos = new long[nCount]; c~0VNuN
nEndPos = new long[nCount]; eHnei F
for(int i=0;i<nStartPos.length;i++) "u,~yxYWl
{ 5EV8zf
nStartPos = input.readLong(); <Hr@~<@~
nEndPos = input.readLong(); 3*2&Fw!B
} {Gb)Et]<
input.close(); gk_Xu
} &>) `P[x
catch(IOException e){e.printStackTrace ();} A\PV@w%Ai
catch(Exception e){e.printStackTrace ();} R^u^y{ohr
} sxC{\iLY%
S{"6PXzb
g*w-"%"O
private void processErrorCode(int nErrorCode) 5f`XFe$8
{ NM.f0{:cj
System.err.println("Error Code : " + nErrorCode); ^kR^ QL$
} {'wU&!
1^H<+0
^)0{42!]
//停止文件下载 {</$ObK
public void siteStop() )S;Xy`vO
{ `w+9j-
bStop = true; 3sg)]3jm2
for(int i=0;i<nStartPos.length;i++) _I70qz8
fileSplitterFetch.splitterStop(); KxTYc
yg[Oy#^
:#&U95EC0
} T=p}By3a
} ~E6+2t*
//负责部分文件的抓取 @Qsg.9N3K
**FileSplitterFetch.java :PjUl
*/ G'}_ZUy#
package NetFox; &LxzAL,3!
/jL{JF>I
sp|y/r#
import java.io.*; [q+39
import java.net.*; !#|fuOWe
%Pvb>U(Xs
!\k#{ 1[!
public class FileSplitterFetch extends Thread { 4z3$
I\4`90uBN
X9`C2fyVd
String sURL; //File URL :;#}9g9
long nStartPos; //File Snippet Start Position w-Q 6 -
long nEndPos; //File Snippet End Position `_{'?II
int nThreadID; //Thread's ID WO*WAP)n
boolean bDownOver = false; //Downing is over -{amzyvLE
boolean bStop = false; //Stop identical me`$5Z`
FileAccessI fileAccessI = null; //File Access interface [;LPeO
\g[f4xAV
A[,"jh
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Ug'nr
{ uu/7Ie
this.sURL = sURL; 0@/E%T1c"
this.nStartPos = nStart; .STf
this.nEndPos = nEnd; NwuBe:"@
nThreadID = id; (lck6v?h
fileAccessI = new FileAccessI(sName,nStartPos);//定位 PQ#-.K
} ,c %gwzU
Q@.9wEAJ
_.8]7f`*Gc
public void run() ^l2d?v8
{ ;@-5lCvC(+
while(nStartPos < nEndPos && !bStop) !+VN
{ 9DAwC:<r
FEi,^V
-8kW!F
try{ Eq.zCD8A
URL url = new URL(sURL); nhxd
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); K[;,/:Y
httpConnection.setRequestProperty("User-Agent","NetFox"); LUVJ218p
String sProperty = "bytes="+nStartPos+"-"; D~?*Xv]s~
httpConnection.setRequestProperty("RANGE",sProperty); ZZJ"Ny.2
Utility.log(sProperty); YZtA:>;p
CpdY)SMSL
x3F L/^S
InputStream input = httpConnection.getInputStream(); #K*q(ei,7h
//logResponseHead(httpConnection); ]x{H
mb6?$1j
[goPmVe+
byte[] b = new byte[1024]; #"YWz)8
int nRead; H9m2Whq
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ?-v?SN#
{ I:)#U[tn0
nStartPos += fileAccessI.write(b,0,nRead); >oYwzK0&
//if(nThreadID == 1) $[;eb,
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); \J g#X:d
} F88SV6
Pw{{+PBu R
@%85k/(
Utility.log("Thread " + nThreadID + " is over!"); .{ Lm
bDownOver = true; 3'uES4+r
//nPos = fileAccessI.write (b,0,nRead); Z"nuO\zH~
} DQXx}%Px
catch(Exception e){e.printStackTrace ();} 7Ki7N{Kt
} m64\@ [
} ]`U?<9~Ob
z#67rh{
D(?#oCCA
//打印回应的头信息 0#GwhB
public void logResponseHead(HttpURLConnection con) J-?(sjIX
{ %Ne>'252y
for(int i=1;;i++) Mo r-$a8
{ #`wfl9tj
String header=con.getHeaderFieldKey(i); R.$Y1=U6
if(header!=null) D"aQbQP
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 6j![m+vo%
Utility.log(header+" : "+con.getHeaderField(header)); WoR**J?}w
else 5 :>
break; v333z<<S
} I9&<:`
} / UBAQ8TR
DuZ]g#
0n^j 50Yq
public void splitterStop() J=bOw//
{ dL"i\5#%A
bStop = true; "2j~3aWj
} vv_?ip:t
du)G)~
ZWW}r~d{
} pDN,(Ip
#>NZN1
[$+61n}.12
/* ho<#i(
**FileAccess.java nXW1:
*//文件访问(定位，写) ]&BFV%kw
package NetFox; 3Or3@e5r
import java.io.*; b=go"sJ@>(
Um&@ 0C+L
M" \y2
public class FileAccessI implements Serializable{ ^<b.j.$<z
0+h?Bk
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 5lY9
RandomAccessFile oSavedFile; KwyXM9h6=
long nPos; M,lu)~H
MkG->*
RH'R6
public FileAccessI() throws IOException J#nEGl|a
{ SjU6+|l
this("",0); m8`A~
} 1 crjRbi
Xb;`WE gC
6P$q7G
public FileAccessI(String sName,long nPos) throws IOException 8b $7#
{ .=D6<4#t
oSavedFile = new RandomAccessFile(sName,"rw"); :v48y.Ij7s
this.nPos = nPos; ;W:Q}[
oSavedFile.seek(nPos); 7%WI
} O;tn5
?+_"2XY
(ZJ_&8C#
public synchronized int write(byte[] b,int nStart,int nLen) > [7vXm4
{ m 9Q{)?J7
int n = -1; CiFbk&-g
try{ Ha\hQ'99
oSavedFile.write(b,nStart,nLen); Rh^$0Q*2
n = nLen; 2|EoP-K7
} ]e9kf$'
catch(IOException e) I}{eYXh
{ 0U~JSmj:2K
e.printStackTrace (); }%|OnEk"
} <9vkiEo
y3GIR f;>
C<ljBz`,t
return n; ~a Rq\fx{
} Ja2.1v|r.
nwYeOa/t
,kI1"@Tu
} wVB8PO8
iBt5aUt
re2%e-F"
/* a!.8^:B&
**SiteInfoBean.java XO>Y*7rO
*/ *QJ/DC$
package NetFox; Pr"ESd>Y
qKXn=J/0tA
s,=^V/c
public class SiteInfoBean { v%w]Q B
fk_i~K
_9dV 3I
private String sSiteURL; //Site's URL a1&^P1.
private String sFilePath; //Saved File's Path hCrgN?Mz
private String sFileName; //Saved File's Name 7tQiKrhp
private int nSplitter; //Count of Splited Downloading File LgYzGlJp
E&AR=yqk
w.jATMJ)F
public SiteInfoBean() X;0@41t'
{//nSplitter的缺省值为5 /:)4tIV
//default value of nSplitter is 5 *@Z'{V\
this("","","",5); oc3/ IWII
} ]0O$2j_7
}#1{GhsS
Q*5d~Yr]R
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) bBf+z7iyc
{ |m%&Qb
sSiteURL= sURL; TfOZ>uR"g
sFilePath = sPath; O_q_O
sFileName = sName; s&l[GKR
this.nSplitter = nSpiltter; +J}M$eQ
8,Z0J
6Xa2A6
} :0l(Ll KD
))vwofkw4
go@}r<B$
public String getSSiteURL() t&0p@xLQ
{ iJK9-k~
return sSiteURL; ~a}pYLxl
} 4KKNw9L)
zq#o8))4X
8~bPoWP
public void setSSiteURL(String value) 3ml|`S
{ HD>{UU?
sSiteURL = value; utXcfKdt
} i8]r}a
!WmpnPr1
w@4+&v>O
public String getSFilePath() @9L9c
{ l d@^$
return sFilePath; 5y)kQ<x"
} Z'~5L_.]Ai
,^(T^ -
3y!CkJKv
public void setSFilePath(String value) YY9q'x,w
{ TFhj]r^{
sFilePath = value; UTz;Sw?~hw
} DRnXo-Aaj
-p1arA
`@90b4u
public String getSFileName() oj/tim
{ %2{E'^#)p-
return sFileName; BBDOjhik
} hf'3yEm
n\ZFPXP
5"sF#Y&
public void setSFileName(String value) ifkA3]
{ j(SQNSFD
sFileName = value; _i&\G}mrC
} c:bB4ch}
(?Yz#Yf
AxeWj%w@
public int getNSplitter() >/>a++19
{ hN.#ui5 $
return nSplitter; JBqzQ^[n
} j EX([J1
]Vubz54
4xlsdq8`t
public void setNSplitter(int nCount) &HE8O}<>
{ REJ}T:
nSplitter = nCount; ;rFa I^
} srCjq
} biJU r^n
%ug`dZ/
t :_7O7
/* wNPZ[V:
**Utility.java |(/"IS]
*/ F'K{=
package NetFox; *6h.#$\
</fnbyGR
I%ez_VG
public class Utility { Lh+^GQ
T]:5y_4?[
@cx!m
public Utility() 6x{B
{ aRV<y8{9
1F=x~FMvY
6@d( <Z
} 9SrV,~zD
TiOvrp7B
//线程睡眠 NzEuiI}
public static void sleep(int nSecond) }b-?Dm_H
{ W] lFwj
try{ NENbr$,G
Thread.sleep(nSecond); p%?R;W`u2
} 'HC4Q{b`
catch(Exception e) F2u{Wzr_@
{ |h3YL!
e.printStackTrace (); 'd28YjtoX
} rlds-j''
} /q>"">
{u:DC4eut
//日志 hGpaHY>My
public static void log(String sMsg) v/kYyz
{ =.uE(L`]NA
System.err.println(sMsg); }NUP[%
} 8T%z{A1T
M]&9Kg3
<mpkkCl,
public static void log(int sMsg) ;xb:{?
{ EZ$m4:{e
System.err.println(sMsg); k`N)-`O7
} eX=W+&lj
} AttDD{Ta
Q%85,L^U
fQv^=DI#
/* 4WNWn#M
**TestMethod.java <5nz:B/
*/ O=yUAAD$
package NetFox; Ly^r8I
0iwx$u7[
k:c)|2
public class TestMethod { !7_Q_h',
j/9'L^]
a.q=
public TestMethod() 8&3G|m1-2
{ ///xx/weblogic60b2_win.exe m:'fk;khN
try{ N!,@}s
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); zW\&q!`IRP
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); (_d^iZyf
SiteFileFetch fileFetch = new SiteFileFetch(bean); /N~.,vf
fileFetch.start(); :#+VH_%N
} fSSDOH!U,
catch(Exception e){e.printStackTrace ();} +4)Kc9S#
VPf=LSxJe
HQ]g{JVld\
} "6.kZ$`%
dfk=%lZYd9
R7vO,kZ6Q
public static void main(String[] args) )4DF9JpD
{ xvb5-tK -
new TestMethod(); JD,/oL.KA
} A9[l5E
} 32dR`qb
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