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)); ,HZYG4,
} c_#*mA"+
for(int i=0;i<nEndPos.length-1;i++) Rv<L#!; t
{ ^2EhlK^)
nEndPos = nStartPos[i+1]; }%$OU =T
} *hF^fxLbl
nEndPos[nEndPos.length-1] = nFileLength; 09d9S`cS\
} <#y*h8IZ@t
} wX0l?xdI
_8^0!,j
Q ]"jD#F
//启动子线程 F}'wH-qp
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; X'x3esw w
for(int i=0;i<nStartPos.length;i++) D,Lp|V
{ n?:2.S.8
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ]v\^&7pW
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ;'}'5nO=$
nStartPos,nEndPos,i); i6Qb[\;
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); T#@{G,N
fileSplitterFetch.start(); H@D;e
} F.?01,J=1
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), b/u8} J
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); e[{mVhg4E
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 'w.}2(
nEndPos = " + nFileLength); ,hWcytzEw
// fileSplitterFetch[nPos.length-1].start(); =IZ[_ /@
RBE7485
\0?$wIH?
//等待子线程结束 3+>OGwfQ
//int count = 0; a8Uk[^5
//是否结束while循环 uE`r/=4
boolean breakWhile = false; "Zcu[2,
|9IC/C!HC
?YBaO,G9o
while(!bStop) ]g,lRG
{ J\=a gQ
write_nPos(); Xwq]f:@V
Utility.sleep(500); j;\[pg MR/
breakWhile = true; d>|;f
q@l(Qol
m[:K"lZ ]2
for(int i=0;i<nStartPos.length;i++) ]-:6T0JuS
{ "|t!7hC
if(!fileSplitterFetch.bDownOver) sn"fK=,#g
{ {<K=*rrZ
breakWhile = false; 9x?'}
break; 8sg|MWSU
} ?:igumeYX
} E'EcP4eL
if(breakWhile) ){P^P!s$
break; ?pG/m%[
=45W\
kRlA4h1u_$
//count++; q]FBl}nwl%
//if(count>4) 9S>g6}[E#0
// siteStop(); +sf .PSz$
} !^WHZv4
S^N{wZo
:(,mL2[
System.err.println("文件下载结束！"); 89HsPB1"t
} |m;L?)F<
catch(Exception e){e.printStackTrace ();} S6sq#kcH
} @AQwr#R"l
`}fw1X5L
|cd-!iJX-
//获得文件长度 66\jV6eH7L
public long getFileSize() +Gh7^v|"
{ Qxa{UQh}9
int nFileLength = -1; D4Etl5k
try{ (=c1
URL url = new URL(siteInfoBean.getSSiteURL()); h@1!T
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); <)U4Xz?
httpConnection.setRequestProperty("User-Agent","NetFox"); 5 1dSFr<#
(D7$$!}
_<*Hv*Zm
int responseCode=httpConnection.getResponseCode(); 4W;S=#1
if(responseCode>=400) (Rd$VYuf
{ gzdG6"
processErrorCode(responseCode); obo&1Uv,/
return -2; //-2 represent access is error 80;n|nNB
} FTf<c0
2SG$LIV 9Y
J7+w4q~cB`
String sHeader; BKIjNV3
|+}G|hx@9
O!&,5Dy
for(int i=1;;i++) F9flSeN
{ wtH~-xSB|
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); XP3xJm3
//Utility.log(in.readLine()); p|[B =.c{
sHeader=httpConnection.getHeaderFieldKey(i); WZn.;
if(sHeader!=null) <1"+,}'x
{ )L5i&UK.
if(sHeader.equals("Content-Length")) X.FGBR7=q
{ w>e s
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); igC_)C^i>
break; c#cx>wq9
} k)7{Y9_No
} X}A'Cg0y
else xDLG=A%]z
break; /+|#^:@
} =L]Q2V}
} !{%&=tIZ
catch(IOException e){e.printStackTrace ();} !3qVB
catch(Exception e){e.printStackTrace ();} =#xK=pRy;
e0HfP v_
F0lOlS
Utility.log(nFileLength); v)X\GmW7w
~E5z"o6$
;zH HIdQ>-
return nFileLength; (u1m]WYL
} ~nY]o"8D
}q[Bd
>BVoHt~;
//保存下载信息（文件指针位置） e'9r"<>i
private void write_nPos() }} ZY
{ rS8 w\`_
try{ ~O6\6$3b5E
output = new DataOutputStream(new FileOutputStream(tmpFile)); nH-V{=**
output.writeInt(nStartPos.length); O XP\R
for(int i=0;i<nStartPos.length;i++) g(4bBa9y
{ n/4i|-^
// output.writeLong(nPos); mY7>(M{
output.writeLong(fileSplitterFetch.nStartPos); qxOi>v0\H
output.writeLong(fileSplitterFetch.nEndPos); #UP~iHbt\
} Ond'R'3\E
output.close(); WT\<.Py
} YN/}9.
catch(IOException e){e.printStackTrace ();} [g|Y7.j8
catch(Exception e){e.printStackTrace ();} Rl~T$ Ey
} 60>.ul2
Vu8,(A7D%O
!wz/cM;
//读取保存的下载信息（文件指针位置） 6<76H
private void read_nPos() ~NcQ1.
{ BMyzjteS+
try{ /RnTQ4
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); #FxPj-3(ix
int nCount = input.readInt(); jM)C4ii.-$
nStartPos = new long[nCount]; k@mVxnC
nEndPos = new long[nCount]; 4=8QZf0\
for(int i=0;i<nStartPos.length;i++) \;X+X,M
{ Vr.Y/3N&'
nStartPos = input.readLong(); dtt~ Bd
nEndPos = input.readLong(); cC{"<fYF
} yHo[{,4itA
input.close(); RW'nUL?_\
} 07v!Zj
catch(IOException e){e.printStackTrace ();} l@Z6do
catch(Exception e){e.printStackTrace ();} ay )/q5
} #U mF-c
}iB|sl2J
hsRvr`#m|
private void processErrorCode(int nErrorCode) LPd\-S_rsP
{ Ol_q{^
System.err.println("Error Code : " + nErrorCode); #dxgB:l)%l
} J9~i%hzr
O[@q%&_
pKG<Nvgz&
//停止文件下载 (5L-G{4
public void siteStop() !U%T&?E l
{ >w6taX
bStop = true; 08bJCH
for(int i=0;i<nStartPos.length;i++) Q n)d2-<
fileSplitterFetch.splitterStop(); V N{NA+I
h&&6r\4/|
*jq7X
} "_UdBG
} }n:?7
//负责部分文件的抓取 >R,'5:Rw
**FileSplitterFetch.java U&Wwyu:4i
*/ pmvT$;7I
package NetFox; ^"\s eS
8)*2@-Rp
)j l8!O7
import java.io.*; VSX@e|Nj
import java.net.*; w'4AJ Q|;
:nN1e
W*DVi_\$y
public class FileSplitterFetch extends Thread { =<@2#E)
!|waK~jK
:(|'S4z
String sURL; //File URL E_z;s3AXQ
long nStartPos; //File Snippet Start Position uQ$^;Pr
long nEndPos; //File Snippet End Position :'L2J
int nThreadID; //Thread's ID CbBSFKM
boolean bDownOver = false; //Downing is over e>rRTN
boolean bStop = false; //Stop identical wBj-m
FileAccessI fileAccessI = null; //File Access interface 2|iV,uJ&
r;>+)**@vl
Xr63?N
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException BAj-akc f
{ #hfuH=&oh
this.sURL = sURL; POI.]1i
this.nStartPos = nStart; _Q%vK*n
this.nEndPos = nEnd; ^g1f X1
nThreadID = id; S{]7C?4`
fileAccessI = new FileAccessI(sName,nStartPos);//定位 0-Y:v(|.
} +yob)%
%sBAl.!BN
&.13dq
public void run() MB ju![n
{ Qp,DL@mp>8
while(nStartPos < nEndPos && !bStop) `N//A}9
{ ]Y>h3T~
U6ZR->:
mbRqJT>@
try{ gF=jf2{YX
URL url = new URL(sURL); WF&[HKOy/
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ^efb 5
httpConnection.setRequestProperty("User-Agent","NetFox"); O%~jop7#6
String sProperty = "bytes="+nStartPos+"-"; `vG,}Pt]
httpConnection.setRequestProperty("RANGE",sProperty); d,vNem-Z*L
Utility.log(sProperty); h}_~y'^!
<:FP4e "(
u=F+(NE"
InputStream input = httpConnection.getInputStream(); \6?A!w~6
//logResponseHead(httpConnection); #o/H~Iv
5Z/GK2[HL
hRI"y":zD
byte[] b = new byte[1024]; >7`<!YJkK
int nRead; _-!sBK+F
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) &;,,H< p
{ UUKP"
nStartPos += fileAccessI.write(b,0,nRead); LH 3}d<{
//if(nThreadID == 1) p9U?!L!y
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 3nZ9m
} OJN2z
5 8-e^.
f %lD08Sl
Utility.log("Thread " + nThreadID + " is over!"); Sd/?&
bDownOver = true; "vYE+
//nPos = fileAccessI.write (b,0,nRead); @l1
} +x?#DH-
catch(Exception e){e.printStackTrace ();} $8USyGi3J
} m=AqV:%|
} *%w69#D
Ut-B^x)gl
{qW~"z*
//打印回应的头信息 P&d"V<
public void logResponseHead(HttpURLConnection con) b*;"q9u5
{ 2$_9cF Wm
for(int i=1;;i++) ^,F;M`[
{ 6$a$K,dZ
String header=con.getHeaderFieldKey(i); $WYbm}j
if(header!=null) I$NhXZ)KT
//responseHeaders.put(header,httpConnection.getHeaderField(header)); EV#MQM
Utility.log(header+" : "+con.getHeaderField(header)); tt?58dm|
else -7/s]9o'
break; O1 .w,U
} <^b7cOFQ
} G2LK]
<H1`
n,eJ$2!J
public void splitterStop() YSJy`
{ F/m^?{==~*
bStop = true; -LDCBc"
} *#%9Rp2|
PkE5|d*,
SvN9aD1
} {U 'd}Q
4Wy<?O2
A7!g
/* 72sD0)?A
**FileAccess.java 6C>_a*w
*//文件访问(定位，写) }pk#!N
package NetFox; yc2/~a_Gx
import java.io.*; RsU3Gi_Zdz
{7cX#1
EM7+VO(
public class FileAccessI implements Serializable{ 2oa#0`{
%8*64T")
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 {GvTfZfp
RandomAccessFile oSavedFile; V._6=ZJ
long nPos; "G-1>:
aK,z}l(N
gH2,\z`[4
public FileAccessI() throws IOException <9=9b_z
{ {QBB^px
this("",0); x}U8zt)yD3
} ze_{=Cv&Y
Wv__ wZ
`28};B>
public FileAccessI(String sName,long nPos) throws IOException %}86D[PF
{ M :3u@06a
oSavedFile = new RandomAccessFile(sName,"rw"); ] 2DH;
this.nPos = nPos; ZYf2XI(_"
oSavedFile.seek(nPos); U.AjYez
} pA{ 5V9
*Nyev]8
^qCkt1C-M
public synchronized int write(byte[] b,int nStart,int nLen) LG~S8u
{ JKer//ng4
int n = -1; !R*-R.%
try{ Q^p|Ldj
oSavedFile.write(b,nStart,nLen); h/x0]@M&
n = nLen; $^&ig
} [Q\GxX.
catch(IOException e) ?u4INZ0W
{ <Dx]b*H
e.printStackTrace (); @ S<-d
} 8 #ndFpu
LPG`^SA
%{3 aW>yx
return n; UgWs{y2SE.
} nR4y`oP+
:{NC-%4o0
c}3W:}lW
} ^QuiH'
=%zLh<3v
K^_i%~
/* e]=!"nJ+
**SiteInfoBean.java USN8N (
*/ "NRDNqj(
package NetFox; !6Sd(2
!*2%"H*
dd?x(,"A`
public class SiteInfoBean { 0y&I/2
8/z3=O&
SuZ&vqS
private String sSiteURL; //Site's URL Z):n c% S
private String sFilePath; //Saved File's Path R3k1RE2c&g
private String sFileName; //Saved File's Name kNu'AT#3|
private int nSplitter; //Count of Splited Downloading File `h}q Eo`
9N%JP+<89
H _Va"yTO6
public SiteInfoBean() nhG J
{//nSplitter的缺省值为5 "O8gJ0e
//default value of nSplitter is 5 IVlf=k
this("","","",5); ) 'j:
} [~:-&
SWp1|.=Sm
zqDR7+]
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) do uc('@
{ XC7%vDIt
sSiteURL= sURL; B2Xn?i3 l
sFilePath = sPath; @"T"7c?Cv
sFileName = sName; $+}+zZX5
this.nSplitter = nSpiltter; FgL,k
+n}$pM|NKU
PSawMPw
} tNVV)C
%gnM(pxl
gX{loG
public String getSSiteURL() TpA\9N#$
{ fQLt=Lrp
return sSiteURL; ,@m@S^
} A`{y9@h(
s:00yQ
c*d9'}E
public void setSSiteURL(String value) 3:%QB9qc]'
{ j@Qg0F
sSiteURL = value; &R~n>>c
} qo)?8kx>l
3D9!M-
Pmi#TW3X
public String getSFilePath() /~4"No@
{ %!ebO*8q
return sFilePath; b|SE<\
} K ~44i
CIjZG?A
LJX-AO.4
public void setSFilePath(String value) )} DUMq7
{ pf4 ^Bk}e
sFilePath = value; Ifk#/d
} s] /tYJYl
/v095H@
!L5jj#0
public String getSFileName() o;b0m;~
{ Lp5U"6y
return sFileName; PX|=(:(k
} XWJwJ
EkT."K
5unG#szq
public void setSFileName(String value) g~UUP4<$"
{ "o& E2#
sFileName = value; (wc03,K^
} +l^LlqA
5-)#f?
9;yn}\N `
public int getNSplitter() 74<!&t
{ PNW \*;j
return nSplitter; 7^}Ll@
} 0iCPi)B
1B*WfP~
Qr#1u
public void setNSplitter(int nCount) OdMO=Hy6d
{ ?Z\Yu'
nSplitter = nCount; (><zsLs&
} gBu1QviU
} hVjNZ
~f|Z%&l|
uH3D{4
/* UEak^Mm;=2
**Utility.java hzI*{
*/ O7']
package NetFox; u6:pV.p
xr0haN\p"
$o@R^sJ
public class Utility { +Taa!hfys
,? E&V_5
9>/wUQs!]
public Utility() iE0ab,OF
{ \3Oij^l0
eMK+X \
TG n-7 88
} VcK}2<8:+~
^4%Zvl
//线程睡眠 PR<||"03
public static void sleep(int nSecond) fIoIW&iy
{ h5 Vv:C
try{ +b;hBb]R
Thread.sleep(nSecond); W{XkVKe1a
} =1dI>M>tm
catch(Exception e) ]IJRnVp%
{ ctQbp~-
e.printStackTrace (); r%Rs0)$yj
} 6VD1cb\lF
} ryO$6L
fJjgq)9
//日志 iq?#rb P#I
public static void log(String sMsg) 9^P2I)aD
{ dAJ,x =`
System.err.println(sMsg); '+<(;2Z vL
} F?Ju??O
`,wu}F85
PXP`ZLF
public static void log(int sMsg) ')+0nPV
{ 31Cq22"
System.err.println(sMsg); {5c]Mn"r
} N#N0Q0W=
} ~;-9X|
9?+9UlJ7K
mzL[/B#>M
/* ]O:M$ $
**TestMethod.java NGjdG=,
*/ E_$z`or
package NetFox; 'f?.R&sCA
JU0]Wq<^[
%R_{1GrL'c
public class TestMethod { ?_6YtR,{
b|^I<7
wh 0<Uv
public TestMethod() t$^l<ppQ
{ ///xx/weblogic60b2_win.exe D)='8jV7
try{ YHxbDf dA
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); #nyv+x;
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); >L((2wfiN
SiteFileFetch fileFetch = new SiteFileFetch(bean); cu#e38M&eE
fileFetch.start(); ]/]ju$l9Z
} ,S[K{y<
catch(Exception e){e.printStackTrace ();} Bt^K]F\
~>ME'D~
%@&a7JOL
} _3Q8n|
Mjpo1dw
OVoO6F]
public static void main(String[] args) L^9HH)Jc
{ >AD=31lq
new TestMethod(); #?}6t~
} "5DJu~
} V7CoZnz
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