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)); \VpN:RI
} }7*|s+F(f
for(int i=0;i<nEndPos.length-1;i++) 'B:8tv
{ (/7b8)g
nEndPos = nStartPos[i+1]; o_8Wnx^
} =kTHfdin&
nEndPos[nEndPos.length-1] = nFileLength; WD55(
} YdDP;, DA
} VBUrtx:
GQ(*k)'a
\sz*M B
//启动子线程 C(8VXtx_
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; O^J=19Ri
for(int i=0;i<nStartPos.length;i++) d.|*sZ&3p
{ e%s1D
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), AL!ppi
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), sZI"2[bk
nStartPos,nEndPos,i); 'ZJb`
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); EXMW,
fileSplitterFetch.start(); Q6T"8K/
} Fr~\ZL
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 5S<Rz)1r
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); #_eXybUV
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", L{&>,ww
nEndPos = " + nFileLength); zLgc j(;
// fileSplitterFetch[nPos.length-1].start(); !2kM
%QG3~b% h
uK]-m
//等待子线程结束 5dGfO:Dy_
//int count = 0; <2d)4@B=
//是否结束while循环 Pbd[gKX_
boolean breakWhile = false; _@i-?Q
)DmydyQ'
}uNj#Uf
while(!bStop) mqHcD8X
{ wPEK5=\4Ob
write_nPos(); mv>0j<C91
Utility.sleep(500); mPU}]1*p
breakWhile = true; @F]w]d
SwsJ<Dq^z
wFF,rUV
for(int i=0;i<nStartPos.length;i++) 3?K+wg s
{ 6cd!;Ca
if(!fileSplitterFetch.bDownOver) A!,c@Kv 3
{ zMRa<G7
breakWhile = false; N5{v;~Cm}V
break; A_l\ij$Y
} w$IUm_~waa
} (/At+MF3E
if(breakWhile) ^vxx]Hji
break; ,,H;2xYf
F!3p )?
:pM)I5MN[
//count++; WH4rZ }Z`
//if(count>4) @<3E`j'p
// siteStop(); DXG`%<ZMn
} X~UL$S;
pV(k6h
Z^]jy>dj
System.err.println("文件下载结束！"); 'z^'+}iyv
} Ypl;jkHP
catch(Exception e){e.printStackTrace ();} ^^&H:q
} =@ acg0
-<g[P_#
e`co:HO`#
//获得文件长度 e/cHH34
public long getFileSize() `+T 2IPN
{ HU'w[r6a
int nFileLength = -1; $@@ii+W}\
try{ 9i U/[d
URL url = new URL(siteInfoBean.getSSiteURL()); &',#j]I
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ^,YTQ.O
httpConnection.setRequestProperty("User-Agent","NetFox"); >-\^)z
sBYDo{01
JN:L%If
int responseCode=httpConnection.getResponseCode(); ^\g.iuE
if(responseCode>=400) yH=<KYk
{ 6/#+#T
processErrorCode(responseCode); '%4fQ%ID}
return -2; //-2 represent access is error W**[:n+
} *+zFsu4l
w,X)g{^T
SHs [te[
String sHeader; Lc?"4
g%tUkM
VQ,5&-9Y3
for(int i=1;;i++) 1TX3/]:
{ tH&eKM4G
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); tvf5b8(Y-
//Utility.log(in.readLine()); ?FNgJx*\S
sHeader=httpConnection.getHeaderFieldKey(i); b1>]?.
if(sHeader!=null) .rG~\Ws
{ w_o+;B|I
if(sHeader.equals("Content-Length")) bl&9O
{ YhNrg?nS
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 45n.%*,
break; )5n0P Zi
} :!l.ze{F
} $W=)-X\>
else -<k)|]8
break; %E/#h8oN{
} +,,dsL
} xOPQ~J|z
catch(IOException e){e.printStackTrace ();} ;~DrsQb
catch(Exception e){e.printStackTrace ();} y\j[\UZKO
G~DHNO6
~Er0$+q=Y;
Utility.log(nFileLength); [T4{K&
JBA{i45x
xv Xci W
return nFileLength; 8\9W:D@"x
} b:'8_jL
@67GVPcxl
0LXu!iix
//保存下载信息（文件指针位置） (SQGl!Lai0
private void write_nPos() *Gv:N6
{ |EdEV*.ej
try{ n:B){'S
output = new DataOutputStream(new FileOutputStream(tmpFile)); A W6B[
output.writeInt(nStartPos.length); g33Y$Xdk
for(int i=0;i<nStartPos.length;i++) :R=7dH~r
{ WV'u}-v^
// output.writeLong(nPos); :CezkD&
output.writeLong(fileSplitterFetch.nStartPos); Z2@e~&L
output.writeLong(fileSplitterFetch.nEndPos); fd #QCs
} xjF>AAM_Px
output.close(); ~:k r;n2
} )7!,_r
catch(IOException e){e.printStackTrace ();} %QrOEs
catch(Exception e){e.printStackTrace ();} ^!C
} x^c,cV+*
c%O97J.5b
aCH;l~+U
//读取保存的下载信息（文件指针位置） c$)>$&([
private void read_nPos() !( +M
{ ]mi\Y"RO
try{ cAGM|%
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); bf=\ED^
int nCount = input.readInt(); hrD2-S
nStartPos = new long[nCount]; Xjxa 2D
nEndPos = new long[nCount]; !]}C!dXd
for(int i=0;i<nStartPos.length;i++) j@#RfVx
{ y{<js!au
nStartPos = input.readLong(); 8@+<W%+th
nEndPos = input.readLong(); N-b'O`C
} fj['M6+wd
input.close(); Cq7 uy
} T%9t8?I
catch(IOException e){e.printStackTrace ();} ]l h=ZC
catch(Exception e){e.printStackTrace ();} B5+Q%)52
} rN7JJHV
)g?jHm-p\
& ^1 b]f
private void processErrorCode(int nErrorCode) ;qy;;usa
{ k<j]b^jbz
System.err.println("Error Code : " + nErrorCode); :-U&_%#w
} @:B}QxC
Y@q9
oiR9NB&<
//停止文件下载 (pM&eow}
public void siteStop() ^fsC]9NS
{ _g9j_ x:=
bStop = true; -DJ,<f*$
for(int i=0;i<nStartPos.length;i++) z79oj\&[
fileSplitterFetch.splitterStop(); As5l36
OAFxf,b
6< -Cpc
} u\iKdL
} oxeIh9 E
//负责部分文件的抓取 gBWr)R
**FileSplitterFetch.java RrH{Y0
*/ |H,WFw1%}
package NetFox; [>_zV.X
9bRUN<
/*e<r6
import java.io.*; 6{udNv X
import java.net.*; 5+Tx01)
8[t*VIXI
hT_Q_1,
public class FileSplitterFetch extends Thread { nO'C2)bBSG
*' es(]W
q9VBK(,X
String sURL; //File URL :/6aBM?
long nStartPos; //File Snippet Start Position v8'XchJ
long nEndPos; //File Snippet End Position .}eM"Kv
int nThreadID; //Thread's ID |{-?OOKj
boolean bDownOver = false; //Downing is over ^x/D8M
boolean bStop = false; //Stop identical })kx#_o]'d
FileAccessI fileAccessI = null; //File Access interface 1ljcbD)T;
_-#o[>2[
x $[_Hix
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ;.xKVH/@
{ {*g{9`
this.sURL = sURL; {,6J*v"o
this.nStartPos = nStart; P_mP ^L
this.nEndPos = nEnd; `-cw[@uD
nThreadID = id; x[)]u8^A
fileAccessI = new FileAccessI(sName,nStartPos);//定位 9An\uH)mL
} U6wy^!_X9
UUbO\_&y
t>LSP$
public void run() ~#VDJ[Z
{ 9vW]HOK
while(nStartPos < nEndPos && !bStop) Y`$\o
{ #u+qV!4
Y=_*Ai
@q>#]8
try{ xQzW6H|
URL url = new URL(sURL); lgK5E*^
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); %|:j=/_
httpConnection.setRequestProperty("User-Agent","NetFox"); ,CPAS}kS
String sProperty = "bytes="+nStartPos+"-"; ez%:>r4
httpConnection.setRequestProperty("RANGE",sProperty); 9M1DE
Utility.log(sProperty); ~Al3Dv9x
}wBpBw2J
huyfo1(
InputStream input = httpConnection.getInputStream(); :i {; 81V
//logResponseHead(httpConnection); cD!E.2[
c05-1
u0)9IZxc
byte[] b = new byte[1024]; vr?u=_%Z
int nRead; Pk(%=P,
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 9&Y|,&W
{ E;'{qp
nStartPos += fileAccessI.write(b,0,nRead); *}Gys/\!S
//if(nThreadID == 1) rK}sQ4z=
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); kD1Nq~h2
} lt]&o0>
r}Gku0Hu_E
5&_")k3$*
Utility.log("Thread " + nThreadID + " is over!"); #cW:04
bDownOver = true; xX{Zh;M&[
//nPos = fileAccessI.write (b,0,nRead); ]mNsG0r6
} uTJz"c`F
catch(Exception e){e.printStackTrace ();} eLgq )
} XDyo=A]
} gcO$T`
& @_PY
Ku uiU= (L
//打印回应的头信息 ci:|x =
public void logResponseHead(HttpURLConnection con) |)0Ta9~
{ (n2_HePE
for(int i=1;;i++) 3,*A VcQA
{ vd$>nJ"
String header=con.getHeaderFieldKey(i); 4m=0e
if(header!=null) 8r@GoG>
//responseHeaders.put(header,httpConnection.getHeaderField(header)); rFm?Bu
Utility.log(header+" : "+con.getHeaderField(header)); c(b`eUOO
else Bf+~&I#E
break; 6CGk*s
} 3fZoF`<a
} ]:T:cO0_n
y@2"[fo3~
KyP@ hhj
public void splitterStop() +;pw^QB
{ pzQc UG
bStop = true; E[zq<&P@
} w~pe?j_F$
oOubqx
Z0'LD<
} mF4OLG3L0
ZZ :*c"b:
0jxXUWO
/* 55] MRv
**FileAccess.java u WdKG({][
*//文件访问(定位，写) cG@Wo8+
package NetFox; kJNg>SN*@#
import java.io.*; ni )G
tux`-F
#SI]^T|
public class FileAccessI implements Serializable{ E&Lml?@
t.O~RE
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 7 TM-uA$
RandomAccessFile oSavedFile; k$#1T +(G
long nPos; [ z/G
Eg2jexl
)S`Yl;oL
public FileAccessI() throws IOException Hv:~)h$
{ H0t#J
this("",0); -=UvOzw
} K9VP@[zbJ
UMFM.GI
a~JZc<ze
public FileAccessI(String sName,long nPos) throws IOException v/$<#2|
{ yOXEP
oSavedFile = new RandomAccessFile(sName,"rw"); V,[[#a)y
this.nPos = nPos; i*&b@.7N
oSavedFile.seek(nPos); g_>E5z.
} n? =O@yq
cf"!U+x
,Tx38
public synchronized int write(byte[] b,int nStart,int nLen) )u]=^
{ _ogN
int n = -1; m@L>6;*
try{ If'N0^'W
oSavedFile.write(b,nStart,nLen); 1E4`&?
n = nLen; pV 8U`T
} S?D]P'<
catch(IOException e) z 3Z8vq
{ E0!0 uSg&
e.printStackTrace (); L7xiq{t`Y
} 9j-;-`$S
M9~'dS'XI
f= }!c*l"
return n; **1=|aa:
} A5%Now;.cf
6-5{7E}/b
&H}Xk!q5b^
} W&I:z-VH
GGZ9DC\{
.]<gm9l
/* XC}2GHO<
**SiteInfoBean.java 30sA\TZ
*/ AxO.adQE%
package NetFox; qzZ;{>_f
oGbh*
"dYT>w
public class SiteInfoBean { dg+"G|nr
X%;4G^%ZI
dEX67rUj;
private String sSiteURL; //Site's URL 5dX0C
private String sFilePath; //Saved File's Path c0X1})q$
private String sFileName; //Saved File's Name p-!/p#
private int nSplitter; //Count of Splited Downloading File )lUocm
q8R,#\T*
'fzJw
public SiteInfoBean() zpNt[F?~1
{//nSplitter的缺省值为5 ]'>jw#|h
//default value of nSplitter is 5 2<AQ{ c
this("","","",5); ew c:-2Y^
} oJE<}~_k
N>sHT =_
!# xi^I
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ye}86{l
{ J~ *>pp#U
sSiteURL= sURL; "/taatcH
sFilePath = sPath; B~O<?@]d
sFileName = sName; *N6sxFs
this.nSplitter = nSpiltter; P.^*K:5@
=dWqB&
Vy=+G~
} 7MKZ*f@x;
-y$<fu9 e
lx~C{tl2
public String getSSiteURL() ys7Tq+
{ y^ st T^
return sSiteURL; &*Kk> 4
} j~9![s!
V9>$M=
VjeF3pmBa
public void setSSiteURL(String value) 3?!c<^"e
{ ]&='E.f
sSiteURL = value; e_S,N0
} (8NE'd8
<Y;w I#C
I-Hg6WtB
public String getSFilePath() ;1r|Bx<5
{ }`76yH^c
return sFilePath; Wk }}f|O0
} $g,v]MW
ZlcEeG
dtV7YPz4+
public void setSFilePath(String value) oGt2n:
{ ZF<$6"4N
sFilePath = value; tq*6]q8c>
} }Cb-7/
@FRas00)|
I(/*pa?m{
public String getSFileName() ? Z2`f6;W4
{ j5~~%
return sFileName; 8\?H`NN
} $KoGh_h
<?Z]h]C^o
eZg>]<L
public void setSFileName(String value) |h.@Xy
{ w,<n5dMv
sFileName = value; 7eFFKl
} ^=gN >xP
_+Pz~_+kS
'PTQ S,E
public int getNSplitter() 2frwU~y
{ ,"?8
return nSplitter; Jgq#m~M6
} 1T4#+kW&
b |ijkys
rWN%j)#+
public void setNSplitter(int nCount) Vw&#Lo
{ )3 '8T>^<K
nSplitter = nCount; 1>bNw-kz7
} +h1X-K:I
} yy`XtJBWWs
n<A<Xj08T9
>52%^ ?
/* xo!2GPD.
**Utility.java Y7')~C`up^
*/ `"#hhKG
package NetFox; F&7^M0x\ O
!2.eJ)G
-^< t%{d
public class Utility { VMu?mqEa
*}>)E]O@
TALiH'w6|e
public Utility() M>{*PHze0
{ @oD2_D2
NjO_Y t
zS`KJVm
} S>s+ nqcP
qv<^%7gq
//线程睡眠 rG%8ugap
public static void sleep(int nSecond) ZT<VDcP{
{ ~sNBklK
try{ sH%Ts@Pl
Thread.sleep(nSecond); wZ_"@j<
} }V 4u`=
catch(Exception e) 5>VX]nE3!
{ Z4sS;k]}
e.printStackTrace (); MIqH%W.ru
} okO\A^F
} ]\/"-Y#4Q
3sl6$NKo
//日志 C4 -y%W"P
public static void log(String sMsg) `yC[Fn"E^
{ HNLr} Yj
System.err.println(sMsg); ~1nKL0C6u
} FyNm1QNy^
D&OskM60
({cWb:+r
public static void log(int sMsg) D"IxQ2}k
{ 5+qdn|9%T
System.err.println(sMsg); TQQh:y
} _SMi`ie#
} ^-"tK:{
r,:acK
ONFx -U]
/* *qFl&*h}
**TestMethod.java #S[Y}-]T
*/ UQbk%K2
package NetFox; x4v&%d=M
lWUQkS
eWr6@
public class TestMethod { p!\GJ a",
#JN4K>_4
i\x@s>@x}
public TestMethod() xWM?E1@
{ ///xx/weblogic60b2_win.exe n"@){:{4?
try{ h+j*vX/!
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); f6{.Uq%SGp
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); \$gA2r
SiteFileFetch fileFetch = new SiteFileFetch(bean); wZ=@0al
fileFetch.start(); #oN}DP
} g@Rs.Zq
catch(Exception e){e.printStackTrace ();} }[(v(1j='~
_`,ZI{.J^
/L./-92NH4
} u~~ ~@p
o[q|dhrANh
8fK/0u^`d
public static void main(String[] args) Qkc9X0J!
{ Q /t_%vb
new TestMethod(); VHvL:z
} [p]UM;+
} Q`Rn,kCVy
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