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)); Z,/BPK<e
} u1a5Vtel
for(int i=0;i<nEndPos.length-1;i++) rMIr&T
{ ,@ A1eX}
nEndPos = nStartPos[i+1]; 2'_xg~
} }:C4T*|
nEndPos[nEndPos.length-1] = nFileLength; ri&B%AAc
} 2bBTd@m4
} ;o]'7qGb
:IDD(<^9
; mF-y,E
//启动子线程 yCZV:R;
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; *(@(9]B~
for(int i=0;i<nStartPos.length;i++) hM^#X,7
{ cUssF%ud]
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), \D(6t!Ox
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 9,=3D2x&
nStartPos,nEndPos,i); Y<M,/Y_ !
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); qy=4zOOD#
fileSplitterFetch.start(); hD!W&Er
} U^SJWYi<Y
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), mMm_=cfv
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ~Emeo&X
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 3eQ-P8LS
nEndPos = " + nFileLength); Qrjo@_+w!
// fileSplitterFetch[nPos.length-1].start(); J<Di2b+
preKg$U
yS0YWqv]6@
//等待子线程结束 @O9.~6
//int count = 0; laN:H mR8
//是否结束while循环 kFmd):U!R
boolean breakWhile = false; %7 h_D
<CIJg*
ko\VDyt,
while(!bStop) s@sRdoTdF
{ !K^.r_0H.
write_nPos(); IBWUXG;
Utility.sleep(500); s 7re
breakWhile = true; ^Ts|/+}'i
|r5 np
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for(int i=0;i<nStartPos.length;i++) /,dcr*
{ x'_I{$C&
if(!fileSplitterFetch.bDownOver) %[0V>
{ |SC^H56+
breakWhile = false; VE5w!of
break; Lbk?( TL
} 3a #2 }
} rlr)n\R#
if(breakWhile) Xwy0dXko
break; =4cK9ac
4hdxqI!y2
T!e]=
//count++; YL\d2
//if(count>4) W]MKc&R
// siteStop(); f.acH]p
} KB49~7XjQ@
|D<J9+
Pn|A>.)z
System.err.println("文件下载结束！"); tcyami6D4
} S4uX utd
catch(Exception e){e.printStackTrace ();} =#]^H c
} 4E]w4BG)
_MQ)
Zyxr#:Qm
//获得文件长度 o-\ K]
public long getFileSize() . (G9mZFV
{ Rhh5r0 \5
int nFileLength = -1; ||3%REliC
try{ !'uL
URL url = new URL(siteInfoBean.getSSiteURL()); V(Ll]g/T_;
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); PjZsMHW%
httpConnection.setRequestProperty("User-Agent","NetFox"); ;Z|X` <6g
7YT%.ID
]w z`j1
int responseCode=httpConnection.getResponseCode(); h`n,:Y^++P
if(responseCode>=400) mn;;wp
{ mxk :P
processErrorCode(responseCode); 8A/"ia
return -2; //-2 represent access is error *TQXE:vZ[
} P6'Oe|+'
0o~? ]C
KDr?<"2L
String sHeader; dPplZ,Y%
GlkTpX^b
NrH2U Jm
for(int i=1;;i++) FJo?~
{ -d]-R?mQ
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 3D L7
//Utility.log(in.readLine()); vAWJP_;J
sHeader=httpConnection.getHeaderFieldKey(i); Bfe#,
if(sHeader!=null) F N6GV
{ "8}p>gS
if(sHeader.equals("Content-Length")) As0E'n85
{ D^ZG-WR
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ;hb;%<xqT
break; e;L++D
} h>\T1PM
} ZXV_Dc
else 5{nERKaPf
break; |#9Nu9ak
} C(-wA
} ?WPuTPw{
catch(IOException e){e.printStackTrace ();} )H@"S]?7i"
catch(Exception e){e.printStackTrace ();} Vb^P{F
2noKy}q
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Utility.log(nFileLength); %(lr.9.]H
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\]RPxM:_>
return nFileLength; 6;s.%W
} buV{O[
pQv`fr=
]DVZeI03@
//保存下载信息（文件指针位置） Qj;wklq
private void write_nPos() K|JpkEw
{ U-~cVk+LI
try{ 52Sq;X
output = new DataOutputStream(new FileOutputStream(tmpFile)); N$>.V7H&
output.writeInt(nStartPos.length); $yxwB/O(
for(int i=0;i<nStartPos.length;i++) d%+oCoeb
{ .j"iJ/
// output.writeLong(nPos); /+^7lQo\]
output.writeLong(fileSplitterFetch.nStartPos); /}+VH_N1
output.writeLong(fileSplitterFetch.nEndPos); \Ps}1)wT
} cV]c/*zA
output.close(); kaM=Fk=t
} zq]I"0Bi.
catch(IOException e){e.printStackTrace ();} 2I'gT$h
catch(Exception e){e.printStackTrace ();} S -$ L2N
} C\"nlNKw
)F_vWbg
WUOoK$I~K
//读取保存的下载信息（文件指针位置） A^lJlr:_`
private void read_nPos() sG-$d\ 1d
{ 8<V6W F`e
try{ L#U-dzy\
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); UuXq+HYR
int nCount = input.readInt(); P?|F+RoX$
nStartPos = new long[nCount]; hr@c7/L
nEndPos = new long[nCount]; )[S~W 35
for(int i=0;i<nStartPos.length;i++) ^`M,ju
{ 2J?ON|2M
nStartPos = input.readLong(); 0"l*8%g
nEndPos = input.readLong(); Y9V%eFY5E
} 6/{V#.(
input.close(); wf*G+&b d2
} bloe|o!
catch(IOException e){e.printStackTrace ();} h8Wv t's
catch(Exception e){e.printStackTrace ();} `^FAD
} k;EG28
r?cDyQE
_0HCtx ;
private void processErrorCode(int nErrorCode) R1'tW=
{ kyV!ATL1F
System.err.println("Error Code : " + nErrorCode); vh+ ' W
} %3p~5jhm1
#63)I9>
117`=9F
//停止文件下载 *xHj*
public void siteStop() =AaTn::e/
{ 4pU|BL\j
bStop = true; :+?eF^5
for(int i=0;i<nStartPos.length;i++) m@(8-_
fileSplitterFetch.splitterStop(); |#OMrP+oi
sA^_I6>M"
iakqCjV
} 0 0JH*I
} .T!R&#]n
//负责部分文件的抓取 pI>yO~Ve
**FileSplitterFetch.java ^7b[spqE
*/ $a /jfpV
package NetFox; Oe#*-
(29h{=P'
qH1k
import java.io.*; a4a/]q4T
import java.net.*; <]:X
,[gu7z^|
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public class FileSplitterFetch extends Thread { k[_)5@2
vI84=n
o<1a]M|
String sURL; //File URL 7E0L-E=.
long nStartPos; //File Snippet Start Position ajr);xd
long nEndPos; //File Snippet End Position _ ^ JhncL
int nThreadID; //Thread's ID !V%h0OE\
boolean bDownOver = false; //Downing is over [u?*' c{
boolean bStop = false; //Stop identical cx+w_D9b!
FileAccessI fileAccessI = null; //File Access interface tccw0
QmHj=s:x\
V1yY>
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException yM_ta '^$
{ F+!w[}0
this.sURL = sURL; U3UKu/Z
this.nStartPos = nStart; K[,d9j`^
this.nEndPos = nEnd; _1>Xk_
nThreadID = id; adCTo
fileAccessI = new FileAccessI(sName,nStartPos);//定位 XIep3l*
} eT!*_.' e
DHI%R<
)Z/L
public void run() hq[:U?!Tt
{ kU75
while(nStartPos < nEndPos && !bStop) rnOg;|u8
{ ejFGeR
NE~R&ym9
HQ187IwpTm
try{ Xl/SDm_p
URL url = new URL(sURL); rofGD9f
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); $Gy&
httpConnection.setRequestProperty("User-Agent","NetFox"); kzkrvC+u
String sProperty = "bytes="+nStartPos+"-"; Sa8KCWgWh
httpConnection.setRequestProperty("RANGE",sProperty); {fd/:B 7T
Utility.log(sProperty); Z91{*?
L- '{
d:<</ah
InputStream input = httpConnection.getInputStream(); ;#i$5L!*B
//logResponseHead(httpConnection); >$/<~j]
uGoySt&;(
!^Ly#$-X
byte[] b = new byte[1024]; 5%6{ ePh{
int nRead; t^k^e{,q#
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) z~m{'O`
{ (GCeD-
nStartPos += fileAccessI.write(b,0,nRead); e>zv+9'Q
//if(nThreadID == 1) eb` !
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Z&Qz"V>$
} 9Z[EzKd<~'
Y^Y1re+}
w'r?)WW$
Utility.log("Thread " + nThreadID + " is over!"); /%9Ge AAs
bDownOver = true; Yl$R$u)
//nPos = fileAccessI.write (b,0,nRead); Xn%ty@8
} V7gv@<1<y
catch(Exception e){e.printStackTrace ();} @H83Ad
} bb4 `s0
} 0[ BPmO6
t@#l0lu$
!T|q/ri
//打印回应的头信息 X]1Q# $b
public void logResponseHead(HttpURLConnection con) Y[R;UJE`5
{ i"_@iN0N
for(int i=1;;i++) \@8.BCWK
{ m)q e
String header=con.getHeaderFieldKey(i); c/'Cju W
if(header!=null) Iq?#kV9)
//responseHeaders.put(header,httpConnection.getHeaderField(header)); <Pnz$nH:e
Utility.log(header+" : "+con.getHeaderField(header)); Sb|9U8h
else >WZ_) `R
break; f(*ygI
} 2?}5U)Hg
} \RF{ITV$kD
LkwjEJQf
sX c|++
public void splitterStop() h>:eu#
{ +7V4mF!u
bStop = true; }o:sU^Pwa
} }\?]uNH
2R`dyg
?= RC?K
} 2mt S\bAF
MXP3ZN'
+ FG Xx
/* K;'s+ZD
**FileAccess.java s[n*fV']A
*//文件访问(定位，写) 1w$X;q"
package NetFox; #*tWhXU
import java.io.*; ]n 'FD|
L5RBe
?l/+*/AR;
public class FileAccessI implements Serializable{ W1\F-:4L@
Ve9*>6i&-4
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 N3m~nEj
RandomAccessFile oSavedFile; "Nh}_jO
long nPos; j&|>Aa${
3$n O@rOS
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public FileAccessI() throws IOException JW2~ G!@
{ ]w5j?h"b
this("",0); 17ol %3 M
} +d289"
,&ld:v?~
rk)h_zN
public FileAccessI(String sName,long nPos) throws IOException 8r\;8all
{ Y7GHIzX
oSavedFile = new RandomAccessFile(sName,"rw"); @\?QZX(H
this.nPos = nPos; 9k*1_
oSavedFile.seek(nPos); Mrly(*!U"@
} sIz*r Gz
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tg"NWp6
public synchronized int write(byte[] b,int nStart,int nLen) Z[%vO?,
{ yk0#byW`
int n = -1; SLjSNuOP
try{ (> VD#n
oSavedFile.write(b,nStart,nLen); 5tUN'KEbN
n = nLen; ,xOOR
} HlgkW&}c^
catch(IOException e) caD|*.b
{ ~ \3j{pr
e.printStackTrace (); nJr:U2d
} :p0<AU47
@w @SOzS)
%<rV~9:
return n; D:.1Be`Tv
} w(cl,W/w
cz.,QIt_
NA{?DSP
} >!BZ>G2
P~9y}7Q\0
i"GCm`
/* 9*CJWS;
**SiteInfoBean.java 9 lH00n+'
*/ 3aERfIJyE
package NetFox; C|g]Y 7
)mh,F#"L
Nu4PY@m]C
public class SiteInfoBean { Kq&JvY^
3v,Bg4[i
?L(y8b}F(
private String sSiteURL; //Site's URL YJqbA?i
private String sFilePath; //Saved File's Path w#w?Y!JXo
private String sFileName; //Saved File's Name ){FXonVP
private int nSplitter; //Count of Splited Downloading File u0i;vO)MNt
3x3 =ke!
~0T,_N
public SiteInfoBean() 5hg ^K^ZZ
{//nSplitter的缺省值为5 ,cwjieM
//default value of nSplitter is 5 BW5!@D2
this("","","",5); 1 R,?kUa
} %O02xr=
o?((FW5.;
<:!;79T\
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ODyKS;
{ )^[PW&=W|x
sSiteURL= sURL; =q"o%dc`R
sFilePath = sPath; _d*QA{
sFileName = sName; 9 =zZ,dg
this.nSplitter = nSpiltter; 0s o27k
t(r}jU=qw
vI5'npM
} Tp&7CNl|
tXW7G@
/PTk296@
public String getSSiteURL() .yN.
{ Xb\de_8!
return sSiteURL; NKRI|'Y,
} AEO7I f@
$G D@e0
*^s^{0Ad
public void setSSiteURL(String value) &A)u!l Ue
{ )Bpvi4O
sSiteURL = value; %?i~`0-:n%
} BU=;rz!;
h$2lO^
*sYvV,
public String getSFilePath() vi~NfD@s
{ Cy2)M(RW
return sFilePath; BaXf=RsZ
} =P7!6V\f
[;,Xp/
)Nkf'&
public void setSFilePath(String value) /4%ycr6
{ @zq]vX-A_
sFilePath = value; Mcm%G#
} Q%.F Mf
TV[@!E a
H?$gHZPI
public String getSFileName() 1<$z-y'
{ ;)ji3M
return sFileName; DWmViuZmL
} dvPlKLp
||o :A
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public void setSFileName(String value) &N|`Q(QXS
{ qg9VK'3o
sFileName = value; +A%"_7L}
} 0o_wy1O1,
-_+,HyJP
O]%Vh l
public int getNSplitter() q&d5V~q
{ R~!md
return nSplitter; NjP7?nXSx
} b1Fd]4H3P
U_61y;Q"
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public void setNSplitter(int nCount) 5rUDRFO6
{ F,/yK-9
nSplitter = nCount; #-9@*FFL,
} T[+~-D @
} ["ML&2|o
TM<;Nj[*n
.V.ga2+
/* ~LSD\+
**Utility.java iiD}2yb
*/ ZxU3)`O
package NetFox; *G(ZRj@33
~%d*#Yxq
K</="3 HK
public class Utility { b|E1>TkY
*7UDTgY
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public Utility() Z<W`5sop^
{ o*Kl`3=]
ObEp0-^?
WR5W0!'Tf
} }/g1s71
y vo4 .u
//线程睡眠 ~?<VT k
public static void sleep(int nSecond) ^gdv:[m
{ 7?a!x$-U(
try{ bXRSKp[$
Thread.sleep(nSecond); (bD'SWE
} vR?E'K3
catch(Exception e) Yu_` >so
{ rO7[{<97m
e.printStackTrace (); Rb l4aB+
} <nbc RO.
} d6+{^v$#
5~\GAjf
//日志 /Q\|u:oO,
public static void log(String sMsg) #5=!ew
{ WN3]xw3
System.err.println(sMsg); 4$MV]ldUI
} ,@r 0-gL
'q, L*
NW`L6wgl
public static void log(int sMsg) SeIL
{ 7xoq:oP-}N
System.err.println(sMsg); K}TSwY
} xF])NZy|
} qJYEsI2M
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WdJJt2'
/* t)^18 z
**TestMethod.java ]D&\|,,(
*/ bPUldkB:
package NetFox; Ys+NIV#Q
gN5;Uk
/\d@AB^5I
public class TestMethod { RAAu3QKu
NNn sq@?6
$ nHf0.V1
public TestMethod() !G~`5?CvE
{ ///xx/weblogic60b2_win.exe #kRt\Fzq
try{ 7O\Qxc\
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); zx`(ojfu
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ) $=!e%{
SiteFileFetch fileFetch = new SiteFileFetch(bean); "s.s(TR8
fileFetch.start(); /nzJ`d
} )UN_,'H/V
catch(Exception e){e.printStackTrace ();} R-OQ(]<*
7p[NuU*Gg
(%SKTM
} %%qg<iO_
Da&Brm
2"8qtG`Et
public static void main(String[] args) ` 3h,Cy^
{ Zx U?d
new TestMethod(); jWcfQ
} Z^6qxZJ7
} 33OkYC%e
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