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)); ?;RY/[IX6
} uqcG3Pi
for(int i=0;i<nEndPos.length-1;i++) U$5x#{AFp
{ J?V$V >d
nEndPos = nStartPos[i+1]; 2B4.o*Q\
} TyV~2pcN
nEndPos[nEndPos.length-1] = nFileLength; L!:NL#M
} I7_8oq\3D
} k<1i.rh
G y[5'J`
_|\X8o_
//启动子线程 $R'?OK(`
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; -1dD~S$
for(int i=0;i<nStartPos.length;i++) >T;!Z5L1
{ $TK*w8@:
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Lyc6nP;F
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), bhD-;Y!6;
nStartPos,nEndPos,i); !Q"L)%)'A
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); -Y524
fileSplitterFetch.start(); }aOqoi7w
} \~8W0q.4M
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 8(Az/@=n
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ~g!!#ad
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", p l^;'|=M
nEndPos = " + nFileLength); ,6]ID1o:y
// fileSplitterFetch[nPos.length-1].start(); YH58p&up
= 9Yfo,F
fuj9x;8X0
//等待子线程结束 VKPEoy8H
//int count = 0; wa,`BAKJ+F
//是否结束while循环 3u j|jwL
boolean breakWhile = false; S }`f&
f2c<-}wR
.QP`Qn6(P
while(!bStop) Y-})/zFc
{ X QLP|v;"
write_nPos(); .iV=ybMT
Utility.sleep(500); -o~zb-E
breakWhile = true; J3y_JoS
#)}BY"C%
C]Fw*t
for(int i=0;i<nStartPos.length;i++) Do(G;D`h+_
{ '|gsmO
if(!fileSplitterFetch.bDownOver) 6Mk#) ebM
{ ; s(bd#Q
breakWhile = false; sq=EL+=j
break; V06*qQ[
} f&$Bjq
} 9iT9ZfaW
if(breakWhile) A o*IshVh
break; 2K_ QZ
6)sKg{H
tC'#dU`=qY
//count++; c9c]1XJ
//if(count>4) #jBmWaP.
// siteStop(); IwYfs]-
} 2@bOy~$A
gH7 +#/
\j!/l f)
System.err.println("文件下载结束！"); =( ZOn=IL
} 346 z`5
catch(Exception e){e.printStackTrace ();} 5$+7Q$Gw
} 7Wef[N\x
=ttD5p
*i*\dl
//获得文件长度 ^nZ=B>Yn2
public long getFileSize() nY MtK
{ WCd:(8B
int nFileLength = -1; F~=kMQO
try{ D)G oWt
URL url = new URL(siteInfoBean.getSSiteURL()); GTB\95j]
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); }],l m
httpConnection.setRequestProperty("User-Agent","NetFox"); &wU"6E
,62~u'hR5
e,#w*|
int responseCode=httpConnection.getResponseCode(); ;S^"Y:7)
if(responseCode>=400) \ o2oQ3
{ KPy)%i
processErrorCode(responseCode); 5 `TMqrk
return -2; //-2 represent access is error M>=@Z*u/+
} ZzK^bNx)0
:kcqf,7
g:RS7od=,
String sHeader; <`-sS]=d}
o.Ww.F
QN;5+p[N
for(int i=1;;i++) Mm,\e6#*
{ M5RN Z%
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); M p<r`PM2
//Utility.log(in.readLine()); #<Y3*^~5d
sHeader=httpConnection.getHeaderFieldKey(i); =~D[M)UO|
if(sHeader!=null) A ___| #R
{ hTO5*5]0zP
if(sHeader.equals("Content-Length")) m^BXLG:b
{ 5vD\?,f E
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); h)sT37
break; EyR/
} vg?(0Gasm*
} G "+[@|
else f\?Rhyz
break; 1d!s8um;
} FLJ&ZU=s
} { #B/4
catch(IOException e){e.printStackTrace ();} prM)t8SE
catch(Exception e){e.printStackTrace ();} \aPH_sf,
w8S pt
,y"vf^BE.
Utility.log(nFileLength); +EA ")T<l
A]Hz?i
y)LX?d
return nFileLength; _GY2|x2c
} cb'Ya_
s8:epcL`A
pno}`Cer
//保存下载信息（文件指针位置） ]~$@x=p2e
private void write_nPos() 1 39T*0C
{ k]gPMhe
try{ p".wqg*W
output = new DataOutputStream(new FileOutputStream(tmpFile)); q%k&O9C2]
output.writeInt(nStartPos.length); <x$nw'H9
for(int i=0;i<nStartPos.length;i++) XU<owk
{ h('5x,G%
// output.writeLong(nPos); !m=Js"
output.writeLong(fileSplitterFetch.nStartPos); GYy8kp84
output.writeLong(fileSplitterFetch.nEndPos); w9u|E46
} ,c&t#mu*0
output.close(); @lM-+q(tl
} B]hRYU
catch(IOException e){e.printStackTrace ();} r]}6iF.
catch(Exception e){e.printStackTrace ();} 3 u=\d)eq
} ~%tVb c
g_PP9S_?
VxOWv8}|
//读取保存的下载信息（文件指针位置） gs0jwI
private void read_nPos() 1Cc91
{ |j/Y#.k;{0
try{ #N`MzmwS
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 1Q^u#m3
int nCount = input.readInt(); nT4Ryld
nStartPos = new long[nCount]; i.K!;E>
nEndPos = new long[nCount]; }X])055S
for(int i=0;i<nStartPos.length;i++) LIJ#nb
{ l'Li!u
nStartPos = input.readLong(); 'rXf
nEndPos = input.readLong(); f3vl=EA4|
} z+M{zr
input.close(); l`6.(6
} _"H\,7E
catch(IOException e){e.printStackTrace ();} &RuTq6)r
catch(Exception e){e.printStackTrace ();} $uwz`N:
} ,|8aDL?
FW2x
{{bwmNv"
private void processErrorCode(int nErrorCode) H#X*OJ
{ /J"fbBXwY
System.err.println("Error Code : " + nErrorCode); !:xE X~
} ":sp0(`h
AW_YlS
z<P?p
//停止文件下载 OP=oSfa
public void siteStop() P1L+Vnfu
{ D@5h$m5
bStop = true; w|I5x}ZFG
for(int i=0;i<nStartPos.length;i++) >sAaLR4
fileSplitterFetch.splitterStop(); 1H%p|'FKA
1bz^$2/k
55`p~:&VQ
} O,+9r_Gh
} o3GZcH?
//负责部分文件的抓取 Nv0a]Am
**FileSplitterFetch.java 4a!%eBhX"K
*/ SH"<f_
package NetFox; um<$L
(-;(wCEE
L>Ze*dt
import java.io.*; "`S?q G
import java.net.*; ',|OoxhbK
Ma{@b$>
7F2:'3SQ
public class FileSplitterFetch extends Thread { 3DCR n :
%WP[V{,F
C\Ob!sv%H
String sURL; //File URL )_Hv9!U]e
long nStartPos; //File Snippet Start Position E@Ewx;P5
long nEndPos; //File Snippet End Position !z:j-gT3
int nThreadID; //Thread's ID 0%|)=T3Slu
boolean bDownOver = false; //Downing is over _h,X3P
boolean bStop = false; //Stop identical #5^OO ou|
FileAccessI fileAccessI = null; //File Access interface fQ.S ,lMe
7N5M=f.DS(
+|<bb8%
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException -)&lsFF
{ G&Yo2aADR
this.sURL = sURL; } nIYNeP?D
this.nStartPos = nStart; L*p7|rq$"
this.nEndPos = nEnd; x~IrqdmW
nThreadID = id; ~rq:I<5
fileAccessI = new FileAccessI(sName,nStartPos);//定位 Xmb##:
} e<8KZ
W?N+7_%'
_TJkYz$
public void run() +?QHSIQo
{ VgY6M_V
while(nStartPos < nEndPos && !bStop) W<O/LHKHdn
{ <Vh5`-J
<Nloh+n=
vy7?]}MvV
try{ 1 K^-tms
URL url = new URL(sURL); {65YTt%
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 5,O:"3>c
httpConnection.setRequestProperty("User-Agent","NetFox"); ZOppec1D
String sProperty = "bytes="+nStartPos+"-"; 9qzHy}A
httpConnection.setRequestProperty("RANGE",sProperty); A;^{%S
Utility.log(sProperty); _ Fk^lDI-
YOfYa
6/'X$}X
InputStream input = httpConnection.getInputStream(); b;vVlIG
//logResponseHead(httpConnection); 2>J;P C[;
XfEp_.~JM
)\W}&9 >
byte[] b = new byte[1024]; 6Y.k<oem
int nRead; LF(S"Of
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) /7a3*a
{ 3c:fYE
nStartPos += fileAccessI.write(b,0,nRead); %rl<%%T#.M
//if(nThreadID == 1) P=E10
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); TL-ALtG
} KZ=5"a
sUkn.g!
W=#jtU`:5
Utility.log("Thread " + nThreadID + " is over!"); l;h -`( 11
bDownOver = true; \f]w'qiW5
//nPos = fileAccessI.write (b,0,nRead); nkN2Bqt$
} C(KV5c
catch(Exception e){e.printStackTrace ();} wk=s3^
} x6\^dVR}
} gA5DEit
|llmq'Q
pJo4&Ff
//打印回应的头信息 )wEXCXr!
public void logResponseHead(HttpURLConnection con) Y'}c$*OkI
{ ]N1,"W}
for(int i=1;;i++) hbx+*KM
{ ,oEAWNbgQ
String header=con.getHeaderFieldKey(i); b$*G&d5
if(header!=null) Jcp=<z*0
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 20A:,pMb
Utility.log(header+" : "+con.getHeaderField(header)); S4E@wLi
else @}%kSn5y:
break; Idj Z2)$
} D [v225
} mndEB!b
,yfJjV*I
JmBMc}54
public void splitterStop() xKT;1(Mk
{ ILHn~d IC
bStop = true; g,RhUt9
} ;>]dwsA*P
Z]OX6G
0h('@Hb.K#
} 4i29nq^n
y7z ,I
LG?b]'#
/* bvJ*REPL?
**FileAccess.java +xr;X 9
*//文件访问(定位，写) 1aUu:#c
package NetFox; #yCnM]cEn
import java.io.*; a^&RV5o
LsK fCB}
tK\$LZ
public class FileAccessI implements Serializable{ "x3!F&
?J"Y4,{
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 `K2vG`c
RandomAccessFile oSavedFile; fKs3H?|
long nPos; CZCVC (/u
2\Yv;J+;
|fn%!d`2
public FileAccessI() throws IOException /DSy/p0%
{ RS7J~Q
this("",0); Vl:M6d1
} (g tOYEqx
MR* %lZpB
(Q|Y*yI
public FileAccessI(String sName,long nPos) throws IOException woU3WS0
{ r6+IJxUd
oSavedFile = new RandomAccessFile(sName,"rw"); 8ePzUc\#
this.nPos = nPos; ;s-fYS6(>{
oSavedFile.seek(nPos); !Ome;gS)
} y8|}bd<Sr
iz`ys.Fu
Lo9 \[4FP
public synchronized int write(byte[] b,int nStart,int nLen) h*mKS -TC
{ z9zo5Xc=
int n = -1; lF$$~G
try{ p"n3JV.~k+
oSavedFile.write(b,nStart,nLen); m&Y?]nbq
n = nLen; w`Rt"d_B
} _b[Pk;8}j;
catch(IOException e) \@7 4I7
{ &KeD{M%
e.printStackTrace (); ZD8E+]+
} b$B-LvHd1
Z Mf,3
O$Dj_R#
return n; J]&nZud`
} 2u}ns8wn
^cojETOv
7"{CBbT
} S`[r]msw
[]H0{a2{<
z|N*Gs>,
/* CDFkH
**SiteInfoBean.java p?+;[!:
*/ CWE^:kr6
package NetFox; 0h"uJco,
.1""U ']
i#Fe`Z ~J
public class SiteInfoBean { ^aL> /'Y#|
95-%>?4
/.m}y$@GV
private String sSiteURL; //Site's URL `Jl_'P}
private String sFilePath; //Saved File's Path MPJ0>Ly
private String sFileName; //Saved File's Name mp0!S
private int nSplitter; //Count of Splited Downloading File HK.Si]:
7+J<N@.d
zXeBUbVi
public SiteInfoBean() MAG/7T5
{//nSplitter的缺省值为5 C2K<CDVw
//default value of nSplitter is 5 elb}] +
this("","","",5); `b[@GGv
} +L}R|ihkI
G#z9=NF~V
hhr>nuA
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Um I,?p
{ ;DI"9
sSiteURL= sURL; g_MxG!+(V
sFilePath = sPath; wafws*b%
sFileName = sName; `>{S?t<
this.nSplitter = nSpiltter; yTU'voE.|
SQf.R%cg$
a~`,zQ -@
} [N*`3UZk"
259:@bi!y
7Y*Q)DDy
public String getSSiteURL() @XX7ydG5
{ d>1#|
return sSiteURL; 7e<\11uI]a
} v7D3aWoe
KKJa?e`C
6NzS<
public void setSSiteURL(String value) #4?:4Im#
{ U{-[lpd
sSiteURL = value; c}#(,<8X
} @-}!o&G0
Z+! 96LR
-<gQ>`(0
public String getSFilePath() x!9bvQT
{ ut9R]01:
return sFilePath; ZvW&%*k=
} l)91v"vJ
VV=6v;u`
]hA]o7k
public void setSFilePath(String value) LfG$?<}hR
{ Kl+4A}Uo
sFilePath = value; dY]iAJ
} K|{&SU_m
q|R$A8)L.
4S,/Z{ J.
public String getSFileName() D$bJs O
{ <e'l"3+9(
return sFileName; SrSm%Dv
} yg@}j
M9sB2Ips<
K/XUF#^B]
public void setSFileName(String value) 3x~AaC.j
{ 15`,kJSK
sFileName = value; #.~lt8F
} VufG7%S{
.[X"+i\
3O'X;s2\d
public int getNSplitter() pB0Do6+{
{ N!=Q]\ZD
return nSplitter; 5[>N[}Ck>
} dZjh@yGP.
,zrShliU
KXga{]G:
public void setNSplitter(int nCount) =?- sazF&
{ N`i`[ f
nSplitter = nCount; %c,CfhEV%&
} 55|.MXzq
} 7!E7XP6,~>
E 5bo60z
Z~Z+Yt;,9a
/* `_H^k!^
**Utility.java _<G%
*/ Y@M l}43
package NetFox; rlVo}kc7:
i"C?6R
Ol. rjz9
public class Utility { de?lO;8
<\S j5
vH9Gf
public Utility() t>>\U X
{ +S>}<OE
yzmwNsu
wPU<jAQyp
} <S%kwS
-)ag9{*
//线程睡眠 H>2f M^
public static void sleep(int nSecond) 7Ke#sW.HN
{ Ty>g:#bogI
try{ T~'9p`IW
Thread.sleep(nSecond); vdN0YCXG
} 66~]7w
catch(Exception e) Dhe ]f#d
{ -,#LTW<.
e.printStackTrace (); z;EnAy{9
} l<mEGKB#
} GCEq3 ^/
-a$7b;gF
//日志 XZ8;Ow=
public static void log(String sMsg) mh8~w~/[
{ aF\?X&|
System.err.println(sMsg); We*)RXm%
} vVi))%&S(
g$ oe00b
wUz)9n 6j
public static void log(int sMsg) uua1_#a
{ *!y.!v*
System.err.println(sMsg); lhA<wV1-9G
} zx{O/v KG
} r'ydjy
pJ1Q~tI
8QGj:3
/* |.Pl[y
**TestMethod.java 'qg q8
*/ mjqVP.
package NetFox; /RmHG H!
_}B:SM
#TX=%x6
public class TestMethod { |O]oX[~
K9y!ZoB
nC5
public TestMethod() NK@G0p~O
{ ///xx/weblogic60b2_win.exe &`'gO 9
try{ O$=)
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); mJ|7Jc
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 8\^[@9g3\3
SiteFileFetch fileFetch = new SiteFileFetch(bean); =Gq 'sy:h
fileFetch.start(); k(;c<Z{?1
} ^f,('0p->
catch(Exception e){e.printStackTrace ();} XHlx89v7
+$+'|w
n'#(iW)f
} 9)qjW&`
?DC3BA\)
N|ut^X+|\
public static void main(String[] args) $v6dB {%Qu
{ 7^~pOFdH
new TestMethod(); -vfV;+3
} {-]/r
} oIM]
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