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)); *#E FsUw
} u2[iMd
for(int i=0;i<nEndPos.length-1;i++) K!:azP,bZ
{ ?6Jx@Sh
nEndPos = nStartPos[i+1]; NYE`Kin-
} 8WtsKOno
nEndPos[nEndPos.length-1] = nFileLength; %JXE5l+pJ
} W=vG$
} 6`O.!|)
TFH\K{DM
mk1bcK9
//启动子线程 SNfr"2c'h~
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; Px$/ _`H
for(int i=0;i<nStartPos.length;i++) ?,p;O
{ +,2:g}5
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), plUZ"Tr
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), RMK"o?
nStartPos,nEndPos,i); eb.O#Y
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 3x5JFM
fileSplitterFetch.start(); [baiH|5>
} t0o`-d(
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), =o Xsb
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Du`JaJI
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", Q o?O:
nEndPos = " + nFileLength); 6qRx0"qB
// fileSplitterFetch[nPos.length-1].start(); `4(e
#,7e NM"
d`P7}*;`
//等待子线程结束 {6"Ph(I1
//int count = 0; >ZPsjQuf"
//是否结束while循环 )Gj8X}DM
boolean breakWhile = false; PUF/#ck
_&N2'hG=sn
TcIcS]w%
while(!bStop) =4[v3Qx
{ \n{qsf:
write_nPos(); IOb*GTb
Utility.sleep(500); :E_g"_
breakWhile = true; xgpi-l
9^,Lc1"M>
3^R&:|,
for(int i=0;i<nStartPos.length;i++) x$IX5:E#e
{ :|_'fNd+!
if(!fileSplitterFetch.bDownOver) &=#[(vl
{ *+-}P|S:
breakWhile = false; X*&[u7No
break; ~p1j`r;
} ]%|GmtqZs,
} ~KW,kyXBnD
if(breakWhile) Qj,]N@7
break; 7[I}*3Q'
7N-w eX
:,Pn3xl
//count++; f#?fxUH~
//if(count>4) h!&prYx
// siteStop(); 94+KdHAo^M
} wT `a3Ymm
LNrX;{ Z
j<u@j+V
System.err.println("文件下载结束！"); 9/hrjItV
} OlAs'TE^
catch(Exception e){e.printStackTrace ();} SF&BbjBE0
} *"D3E7AO
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? i( %
//获得文件长度 >}!mQpAO
public long getFileSize() :X.b}^Z(
{ Ko;{I?c
int nFileLength = -1; 0}$Hi
try{ b+@JY2dvj
URL url = new URL(siteInfoBean.getSSiteURL()); 0|$v-`P$
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); odPL{XFj
httpConnection.setRequestProperty("User-Agent","NetFox"); %K\?E98M
zoOaVV&1
>?6&c
int responseCode=httpConnection.getResponseCode(); Fe]B&n
if(responseCode>=400) x*?x=^I{
{ Rn{iaM2Y<
processErrorCode(responseCode); : y5<go8e
return -2; //-2 represent access is error kBYNf =
} [* @5\NWR}
;k7xMZs
NXNY"r7~
String sHeader; ^zt-HDBR_
;cPy1
>)spqu]
for(int i=1;;i++) !OA]s%u
{ }&n<uUDH
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); BB~OqZIP
//Utility.log(in.readLine()); "Jt.lL ]5
sHeader=httpConnection.getHeaderFieldKey(i); 4zJtOK?r"
if(sHeader!=null) :|Ad:fEs
{ e '2F#
if(sHeader.equals("Content-Length")) W6"v)Jc>_
{ 3 |hHR
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); `0P$#5?
break; #;%JT
} kMtwiB|7j
} x9;gT&@H
else EGZb7:Y?
break; O9EKRt
} fcNL$U&-,i
} .2>p3|F
catch(IOException e){e.printStackTrace ();} QAvir%Y9Q
catch(Exception e){e.printStackTrace ();} &jsVw)Ue
7PANtCFb&
t%'Z<DmG+
Utility.log(nFileLength); gF[z fDm
$: ]o]a
SzUpWy&
return nFileLength; oo=Qt(#
} hjIT_{mk
i?fOK_d
\8<BLmf4U
//保存下载信息（文件指针位置） Hm$=h>rY9[
private void write_nPos() =,Dqqf
{ @6mBqcE'?
try{ d!:6[7X6
output = new DataOutputStream(new FileOutputStream(tmpFile)); xZ4~Oo@@_'
output.writeInt(nStartPos.length); ADpmvW f?
for(int i=0;i<nStartPos.length;i++) du)~kU>l
{ .G+Pe'4a
// output.writeLong(nPos); M@?xa/E64
output.writeLong(fileSplitterFetch.nStartPos); p;W.lcO`0
output.writeLong(fileSplitterFetch.nEndPos); w:?oTuw
} :,J}z~I,lB
output.close(); XLL/4)
} |!"2fI
catch(IOException e){e.printStackTrace ();} L{(QpgHZ
catch(Exception e){e.printStackTrace ();} #B:hPZM1
} O2BW6Wc
|b*? qf
^4,a8`
//读取保存的下载信息（文件指针位置） Sqo :-
private void read_nPos() tI7:5Cm
{ G3rj`Sg^c
try{ hi0R.V&
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); L+CyQq
int nCount = input.readInt(); rMUT_^
nStartPos = new long[nCount]; xfb]b2
nEndPos = new long[nCount]; L2, 1Kt7
for(int i=0;i<nStartPos.length;i++) z.Y$7bf)
{ GKoK7qH\J
nStartPos = input.readLong(); Hd,p!_
nEndPos = input.readLong(); !zPa_`P
} L+'Fs
input.close(); xo&]RYG[<
} ]79:yMD~ba
catch(IOException e){e.printStackTrace ();} ox%9Ph
catch(Exception e){e.printStackTrace ();} fH)YFn/
} D<Zp!J1o
IdXZoY
CMn{LQcC
private void processErrorCode(int nErrorCode) RB+N IoQQ|
{ hWKJ,r%9;
System.err.println("Error Code : " + nErrorCode); nv0]05.4
} t`+'r}=d
vP!{",>
$ZNu+tn Y
//停止文件下载 J,zO2572u
public void siteStop() Q",0F{'
{ v76D3'8
bStop = true; e0J6Ae4V[
for(int i=0;i<nStartPos.length;i++) z,VD=Hnz
fileSplitterFetch.splitterStop(); LrATSq@
Ma+$g1$
bks/`rIA
} ed:@C?
} Z7RiPSdxp
//负责部分文件的抓取 ' 4ER00
**FileSplitterFetch.java ET[kpL
*/ <0S,Q+&
package NetFox; SF5@Vg
i:Zm*+Gi
hs?sGr
import java.io.*; +e-G,%>9
import java.net.*; jiYmb8Q4D
ZKXo-~=>
fgBM_c&9T
public class FileSplitterFetch extends Thread { 1&P<
!w H'b
i| ZceX/
String sURL; //File URL #'q<v"w
long nStartPos; //File Snippet Start Position &[At`Nw71
long nEndPos; //File Snippet End Position 1?| flK
int nThreadID; //Thread's ID 0 s70r
boolean bDownOver = false; //Downing is over 2e|N@j &
boolean bStop = false; //Stop identical ^qC;Nh4F
FileAccessI fileAccessI = null; //File Access interface Ton94:9bZ
3;8!rNN
ZvUCI8
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Y& F=t/U2
{ &`fhEN
this.sURL = sURL; {&"L~>/o
this.nStartPos = nStart; (I@rLvZr{
this.nEndPos = nEnd; eQVZO>)P1+
nThreadID = id; iC*F
fileAccessI = new FileAccessI(sName,nStartPos);//定位 [xT:]Pw}
} EZYBeqv
9 Rx s
o}<4*qlI
public void run() !xwG%{_
{ E"L2&.
while(nStartPos < nEndPos && !bStop) 1Jj Y!
{ 06Gt&_Q
JKX_q&bUw
cW{1 Pz^_
try{ iR\Hv'|
URL url = new URL(sURL); f}L*uw
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 0jzbG]pc:E
httpConnection.setRequestProperty("User-Agent","NetFox"); @o-B{EH8
String sProperty = "bytes="+nStartPos+"-"; l$YC/bP
httpConnection.setRequestProperty("RANGE",sProperty); VL[kJi
Utility.log(sProperty); >/#KI~}'N
_ib"b#
_$p$")
InputStream input = httpConnection.getInputStream(); 3( ]M{4j
//logResponseHead(httpConnection); 7c;9$j
OKHX)"j\\
^::EikpF%
byte[] b = new byte[1024]; P1zdK0TM
int nRead; ~l$3uN[g
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) IJJ%$%F/
{ MgC:b-&5_
nStartPos += fileAccessI.write(b,0,nRead); T<I=%P)
//if(nThreadID == 1) m] W5+
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); uK'&Dam
} !gLkJ)
DaH?@Q
XK"-'
Utility.log("Thread " + nThreadID + " is over!"); Uh'#izm[l
bDownOver = true; Lgz$]Jbl8
//nPos = fileAccessI.write (b,0,nRead); *c)uGz'cD
} /1 RAAa
catch(Exception e){e.printStackTrace ();} \V>?Do7
} +`sv91c
} gt\MS;jMa
:d8W+|1u
cv(PP-'\
//打印回应的头信息 {,cCEXag%
public void logResponseHead(HttpURLConnection con) k/03ZxC-
{ jt@SZI`
for(int i=1;;i++) <F )_!0C
{ 0A:n0[V:]
String header=con.getHeaderFieldKey(i); fGv#s X
if(header!=null) zFQ&5@43
//responseHeaders.put(header,httpConnection.getHeaderField(header)); Q`#4W3-,
Utility.log(header+" : "+con.getHeaderField(header)); !;Jmg
else BI:k#jO!
break; TM8=U-A
} huudBc A[
} 5`]UE7gT
nr)c!8
p7ir*r/2
public void splitterStop() c>1RP5vx
{ ZvGgmLN
bStop = true; UA~RK2k?
} {"vkji>
]hud4i~
>|Q:g,I
} NWfAxkz{/
?k[p<Uo
3M0+"l(X
/* \7z^!m
**FileAccess.java Ke-)vPc
*//文件访问(定位，写) Wy]^Ub gW
package NetFox; 4gSH(*}
import java.io.*; b.O9ITR
J4=_w
muW!xY
public class FileAccessI implements Serializable{ $hR)i
IkzTJ%>
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 #&8}<8V
RandomAccessFile oSavedFile; 0lM{l?
long nPos; }<jb vCeK
NDO\B,7
%~NH0oFO
public FileAccessI() throws IOException <P%}|@
{ ( #Z`
this("",0); Y`6rEA0
} qW_u
%b?$@H-Re
?hYqcT[%
public FileAccessI(String sName,long nPos) throws IOException pWE`x|J
{ WqrgRpM{
oSavedFile = new RandomAccessFile(sName,"rw"); Q6C-4ja
this.nPos = nPos; ?yXAu0
oSavedFile.seek(nPos); Lh$dzHq
} O)R(==P26P
BsZ{|,oQnZ
%m{U& -(l@
public synchronized int write(byte[] b,int nStart,int nLen) 5wC* ?>/
{ ]>i~6!@
int n = -1; jx_4B%kzq
try{ jY!ZkQsVe
oSavedFile.write(b,nStart,nLen); $mA5@O~C5\
n = nLen; IB9%QW"0
} nL]^$J$
catch(IOException e) P5QQpY{<I
{ ']ood!
e.printStackTrace (); /"qcl7F
} t>UkE9=3\
tGcya0RL
! o,5h|\
return n; ]r]k-GZ$
} S\NL+V?7h
eyw'7
d6 _C"r
} h7_)%U<J2
K_-d(
*HM?YhR
/* ,je`YEC
**SiteInfoBean.java P}3}ek1Ax
*/ GgFi9Ffj
package NetFox; 1D([@)^
~H@+D}J?
&[|VZ[
public class SiteInfoBean { mjnUs-`W|
HO|-@yOF^
xcCl (M]+
private String sSiteURL; //Site's URL |E/L.gdP7
private String sFilePath; //Saved File's Path 7_KhV
private String sFileName; //Saved File's Name %NHYW\sKX
private int nSplitter; //Count of Splited Downloading File N1--~e
u~ F;xQ
e5v`;(^M
public SiteInfoBean() GtI6[ :1t
{//nSplitter的缺省值为5 6DSH`-;
//default value of nSplitter is 5 {6vEEU
this("","","",5); |@VF.)_
} bNzqls$
}3/~x
J>S3sP
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) *ftC_v@p5
{ h!]"R<QQdu
sSiteURL= sURL; X.|Ygx
sFilePath = sPath; v1[_}N9f>H
sFileName = sName; 0^!Gib
this.nSplitter = nSpiltter; {0jIY
nZvU'k:
J0<p4%Cf
} f5dR 5G
sroGER.
]= x 1`j
public String getSSiteURL() q7]>i!A
{ Re:T9K'e
return sSiteURL; ?KN:r E
} !r&Bn6*
r)l`
^o<[. )
public void setSSiteURL(String value) x(r+P9f\<
{ cz.3|Lby
sSiteURL = value; 5h_5Z~
} 6nw&$I
pVokgUrC
Wpm9`K
public String getSFilePath() H*!5e0~rR
{ N7. @FK
return sFilePath; X.J
} /#q")4Mf
|+ 7f2C
Q)6va}2ai
public void setSFilePath(String value) #Q6w+"
{ =Lw3 \5l
sFilePath = value; 3XVk#)lw
} E3\ZJjG
ua& @GXvZ
U}P,EP%p
public String getSFileName() ~w.2-D
{ LcUlc)YH5
return sFileName; r\mPIr|
} j 2}v}
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W8/(;K`/
public void setSFileName(String value) i-13~Dk
{ !UNNjBBP7
sFileName = value; ^8742.
} ?V+wjw
P>htQ
V/H@vKN2
public int getNSplitter() STT2o=
{ XJFnih
return nSplitter; E%*AXkJ'dZ
} dq8+m(7k
6F5,3&
/?3:X*
public void setNSplitter(int nCount) NNX%Bq
{ %]jQ48^R
nSplitter = nCount; -Cj_B\
} z>:U{!5k
} 'O "kt T
o>u!CL<
IA4+ad'\E
/* 9v?V
**Utility.java X%J%A-k]
*/ %|?1B$s0
package NetFox; !GNXt4D
1o#vhk/"+
zz3 r<?#5
public class Utility { [:pl-_.C
DcU C,
n0FYfqH
public Utility() + U5U.f%
{ h]}`@M"
3:" &Z6t#
GN%<"I.
} SQIdJG^:
0^iJlR2
//线程睡眠 %gTVW!q
public static void sleep(int nSecond) PN9^[X
{ z[biK|YL
try{ yM17H\=
Thread.sleep(nSecond); ;&`:|Hf*
} >nNl^ yqW
catch(Exception e) SY8U"Qc;9
{ R9E6uz.j
e.printStackTrace (); `t9.xB#Z
} Qg{WMlyOP
} FG _,
{9{J^@@
//日志 $O]^Xm3{@
public static void log(String sMsg) &:#A+4&
{ $[w|oAwi
System.err.println(sMsg); 3se$,QmN
} H oS|f0
mrReast
1w) fu
public static void log(int sMsg) C$ hQN
{ nr<.YeJ
System.err.println(sMsg); M/)B" q
} R}.3|0
} 1O9$W?)Q
,#Ln/;
Nc"NObe
/* AA_@\:w^
**TestMethod.java "_oLe;?$c
*/ 'W+i[Ep5Q
package NetFox; G)4SWu0<t
m/" J s
\3: L Nt
public class TestMethod { 6.UKB<sV
1::LN(`<
K /8qB~J*
public TestMethod() 6*V8k%H
{ ///xx/weblogic60b2_win.exe }2mI*"%)\u
try{ GM77Z.Y
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Q.>/*8R;
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); [{/$9k-aF?
SiteFileFetch fileFetch = new SiteFileFetch(bean); ef,F[-2^o
fileFetch.start(); Ki63Ox^O
} ^K/G5
catch(Exception e){e.printStackTrace ();} ofl'G]/$+
>Ban?3{
l)%mqW%
} 'me:Zd
LAos0bc)w\
.c|9..Cq=
public static void main(String[] args) OU6^+Ta
{ 2\,e
new TestMethod(); CY5w$E
} oM2|]ew)
} *n;>p_#
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