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)); yE\dv)(<
} *)2&gQ&%+
for(int i=0;i<nEndPos.length-1;i++) f_&bwfbo
{ U#jbii6e
nEndPos = nStartPos[i+1]; \*C}[D
} d4h, +OU
nEndPos[nEndPos.length-1] = nFileLength; ?G#T6$E8
} 5Z`9L|3d
} 3+%c*}KC~
V ?10O
V=@M!;'<
//启动子线程 fh1rmet&Ts
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; !i|]OnJY
for(int i=0;i<nStartPos.length;i++) k lRS:\dW
{ U(.3[x
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), s5s'$|h"
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), o+H;ZGT5H
nStartPos,nEndPos,i); kc3dWWPe
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); BtyBZ8P;e
fileSplitterFetch.start(); y8$TU;
} BJM_kKH
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), llf|d'5Nl
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); k0=$mmmPY
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", eQ}o;vJN
nEndPos = " + nFileLength); )V}u}5
// fileSplitterFetch[nPos.length-1].start(); YlZe
TZT1nj"n
S z3@h"
//等待子线程结束 8( ^;h2O!
//int count = 0; Vp;^_,
//是否结束while循环 hJ+;N
boolean breakWhile = false; ;OlC^\e
24TQl<H{
Z;^UY\&X
while(!bStop) z;dD }Fo
{ xwwy9:ze*l
write_nPos(); qL6Rs
Utility.sleep(500); B rGaCja
breakWhile = true; @ (UacFO
ddDl~&}o
,qj
for(int i=0;i<nStartPos.length;i++) 8+Y+\XZG
{ k{/2vV[`]
if(!fileSplitterFetch.bDownOver) 4uW}.7R'
{ ZiBTe,;
breakWhile = false; aj1o
break; }";\8
} FbMX?T"yH
} `TM[7'
if(breakWhile) PYldqY
break; wG1A]OJl1
sLE@Cm]k
:%M[|Fj
//count++; qM(n]{H
//if(count>4) E\5cb[Y
// siteStop(); ~.;S>o[
} 2;@#i*\Y
S!0ocS!t
2TN+ (B#Z!
System.err.println("文件下载结束！"); K)|#FRPM u
} y{~l&zrl
catch(Exception e){e.printStackTrace ();} ~ {sRK
} FF:Y7wXW
hjB G`S#
fL9R{=I%
//获得文件长度 >gAq/'.Q
public long getFileSize() XG fLi
{ Jsee8^_~
int nFileLength = -1; &8R%W"<K
try{ Ol4)*/oZ
URL url = new URL(siteInfoBean.getSSiteURL()); 7xAzd# c?=
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); T<*i($ [
httpConnection.setRequestProperty("User-Agent","NetFox"); ]| oh1q
|A_yr/f
5}3Q}o#
int responseCode=httpConnection.getResponseCode(); r2A(GUz
if(responseCode>=400) _ukKzY
{ S$q:hXZ#e
processErrorCode(responseCode); |I7-7d-;/
return -2; //-2 represent access is error &P>wIbE
} vmI]N
\>NjeMuWU
C<CE!|sfr
String sHeader; Sr)rKc
/esSM~*H
FyN@mX
for(int i=1;;i++) >jjuWO3T
{ ~c7}eTJd"
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 45l/)=@@B
//Utility.log(in.readLine()); ,?;q$Xoi
sHeader=httpConnection.getHeaderFieldKey(i); @; ayl
if(sHeader!=null) \HFeEEKH
{ yyJ4r}TE
if(sHeader.equals("Content-Length")) $a(EF 6
{ LGq}wxq
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); *h Ph01
break; :.B};;N
} =/MAKi}g
} uGl+"/uDu
else 1P&XG@
break; [nBlHI;&
} o >bf7+D
} E<;C@B
catch(IOException e){e.printStackTrace ();} (v*$ExF
catch(Exception e){e.printStackTrace ();} C.dN)?O
Hk%m`|Z
T!eb=oy
Utility.log(nFileLength); '7}s25[{\
ETe,RY
SlvQ)jw%
return nFileLength; az3rK4g
} TfK$tTkM
c,;-[sn
Kl~jcq&z
//保存下载信息（文件指针位置） %76N$`{u
private void write_nPos() <N^2|*3
{ E7^r3#s
try{ ZiodJ"r
output = new DataOutputStream(new FileOutputStream(tmpFile)); +~RiCZt
output.writeInt(nStartPos.length); {4tJT25
for(int i=0;i<nStartPos.length;i++) rwr>43S5<3
{ -%"Kxe
// output.writeLong(nPos); TGu`r>N51
output.writeLong(fileSplitterFetch.nStartPos); Hw[u Sv8
output.writeLong(fileSplitterFetch.nEndPos); 2'W3:
} t>><|~wp
output.close(); e"P>b? OY
} !Y/$I?13Z
catch(IOException e){e.printStackTrace ();} u$d T^c
catch(Exception e){e.printStackTrace ();} 5F$ elW
} n\&[^Q#b|
PO5/j
~7T]l1]W%
//读取保存的下载信息（文件指针位置） ?)k;.<6
private void read_nPos() ]Ow A>fb
{ HkFoyy
try{ +s.r!?49+
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); WPiQ+(pt
int nCount = input.readInt(); Im i)YC
nStartPos = new long[nCount]; 7HzO_u%H1
nEndPos = new long[nCount]; %{g<{\@4(;
for(int i=0;i<nStartPos.length;i++) Y##ftQ
{ V~` ?J6
nStartPos = input.readLong(); }6MHIr=o
nEndPos = input.readLong(); E9t[Mb %0
} _v:t$k#sN
input.close(); _oxhS!.*
} 4~=/CaG~
catch(IOException e){e.printStackTrace ();} {Sm^F
catch(Exception e){e.printStackTrace ();} 8C3oj
} XqMJe'%r
E$dPu
{H{u[XR[z
private void processErrorCode(int nErrorCode) 7<DlA>(oUX
{ hDI_qZ
System.err.println("Error Code : " + nErrorCode); {[QCuR
} $TS4YaJ%
wB~Ag$~
f"j~{b7
//停止文件下载 fvgjqiT
public void siteStop() Ub!MyXd{q
{ ;:NW
bStop = true; G$&SlJZEk
for(int i=0;i<nStartPos.length;i++) f]N2(eM
fileSplitterFetch.splitterStop(); #]pFE.o
/pni_-l*
aj;OG^(!2_
} !2>MaV1,
} -E_lwK
//负责部分文件的抓取 ~ {OBRC
**FileSplitterFetch.java gwwYz]'d>r
*/ udYk 6
package NetFox; <Uf?7
]Gm"U!h*
| wuUH
import java.io.*; c+P.o.k;
import java.net.*; luAmq+
Ao>] ~r0
cC@B\Q
public class FileSplitterFetch extends Thread { >.^/Z/[.L
_s{on/u
co^kP##Y
String sURL; //File URL Bbk=0+ ^8I
long nStartPos; //File Snippet Start Position ^ 'W<|
long nEndPos; //File Snippet End Position .=rS,Tpo
int nThreadID; //Thread's ID hJ[Z~PC\T0
boolean bDownOver = false; //Downing is over iOk^RDG+
boolean bStop = false; //Stop identical T 2Uu/^
FileAccessI fileAccessI = null; //File Access interface 0~2~^A#]\
$e>(M&9,
z2:^Qg
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException {uVvo=3
{ '*K}$+l
this.sURL = sURL; Se*o{V3s$
this.nStartPos = nStart; );X&J:-l+
this.nEndPos = nEnd; ro:B[XE
nThreadID = id; `a*_b9
fileAccessI = new FileAccessI(sName,nStartPos);//定位 <7-Qn(m,
} WBcnE(zF
wQ!C9Gp3e
Z]U"i1lA
public void run() UqJ}5{rt
{ 1?k{jt~
while(nStartPos < nEndPos && !bStop) A{3VTe4TV
{ -.XICKz
&z'NQ!uV
Vqr#%.N
try{ -nM=^i4)
URL url = new URL(sURL); AunX[X9
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ,ddoII
httpConnection.setRequestProperty("User-Agent","NetFox"); s#phs`v
String sProperty = "bytes="+nStartPos+"-"; wrtJ8O(
httpConnection.setRequestProperty("RANGE",sProperty); 9 GEMmo3
Utility.log(sProperty); Ph{7S43
# !:u*1
dY|~"6d)
InputStream input = httpConnection.getInputStream(); 6MsVV_/
//logResponseHead(httpConnection); 8OV;&Z,x
~8fy qE$
X*4iNyIs_
byte[] b = new byte[1024]; Xaz`L
int nRead; H> Y0R
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) $@WqM$
{ ;^fGQ]`4
nStartPos += fileAccessI.write(b,0,nRead); 8\V
//if(nThreadID == 1) Vp"=8p#k
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); l:' 0
} i-kj6N5
#ZzFAt
f}1B-
Utility.log("Thread " + nThreadID + " is over!"); ">-J+ST%
bDownOver = true; 6A$ Y]u
//nPos = fileAccessI.write (b,0,nRead); WR5@S&fU`
} *?l-:bc]
catch(Exception e){e.printStackTrace ();} [Un~]E.'J
} F},#%_4
} 1]DPy+
n:TWZ.9
*O5Ysk^|
//打印回应的头信息 _lK+/"-l
public void logResponseHead(HttpURLConnection con) NA=I7I@
{ .zm/GtOV@
for(int i=1;;i++) uD'GI
{ ca@?-)
String header=con.getHeaderFieldKey(i); %1\MW+
if(header!=null) QGC%, F"+
//responseHeaders.put(header,httpConnection.getHeaderField(header)); KR49Y>s<
Utility.log(header+" : "+con.getHeaderField(header)); W##~gqZ/
else Es7+bFvsE8
break; uT\|jv,
} Xc>M_%+R
} L lNd97Z
,\%qERk
GC#s;X
public void splitterStop() mi`jY0e2
{ O7})1|>1
bStop = true; 3RbPc8($Y
} 9/yE\p.
z\kiYQ6kA
8.Z9 i
} {S$]I)tV
Z)Zc9SVC
Z<Rhn
/* _Hp[}sv4)
**FileAccess.java Yg~$1b@
*//文件访问(定位，写) t[|aM-F&>
package NetFox; lx)Bj6
import java.io.*; >Q-"-X1
u]<_6;_
?as1^~
public class FileAccessI implements Serializable{ =N~*`5|rk
nS` :)#;
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 X+$IaLfCxD
RandomAccessFile oSavedFile; 810pJ
long nPos; Q)s`~G({P
Zr#\>h'c
<rbzsn"a
public FileAccessI() throws IOException X:Iam#H
{ m\DI6O"u'
this("",0); "C~Zl&3
} LJ{P93aq`^
6!|/(~
4\pUA4
public FileAccessI(String sName,long nPos) throws IOException <l`xP)] X
{ i2yE-sgF
oSavedFile = new RandomAccessFile(sName,"rw"); A?;KfVq
this.nPos = nPos; Yp@i{$IUW
oSavedFile.seek(nPos); VX+:C(m~
} D\LXjEme.
"T~ce@
c*N>7IF,
public synchronized int write(byte[] b,int nStart,int nLen) ~6!TMVr
{ H\^zp5/
int n = -1; ?}Y;/Lwx
try{ |qq7vx
oSavedFile.write(b,nStart,nLen); i9=*ls^Cx
n = nLen; NN"!kuM
} 0<$t9:dq
catch(IOException e) av:9kPKm
{ 6)#=@i` \
e.printStackTrace (); )ePQN~#K}
} 7|Bg--G1
U:+wt}-T"
NU/:jr.W#
return n; =*'K'e>P3
} gQ;1SY!
w\{oOlE
+)U>mm,
} <UE-9g5?G
I?~iEO\nh
rI;84=v2&9
/* n/vKxtW
**SiteInfoBean.java UR'P,
*/ sF!nSr
package NetFox; 6Sr}I,DG
/5&'U!:+
96]!*}
public class SiteInfoBean { 01&J7A2
Y-y<gW
'\4 @
private String sSiteURL; //Site's URL ` Clh;
private String sFilePath; //Saved File's Path d7i 0'R
private String sFileName; //Saved File's Name j" ~gEGfK
private int nSplitter; //Count of Splited Downloading File TBr@F|RXiO
G~FAChI8![
e>~7RN
public SiteInfoBean() :}{,u6\
{//nSplitter的缺省值为5 l 4e`-7
//default value of nSplitter is 5 (sN;B)
this("","","",5); %5rC`9^
} bS"zp6Di
:W*']8 M-
`p\@b~GM
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) #a|.cm>6
{ x!^u$5c
sSiteURL= sURL; C'oNGOEd
sFilePath = sPath; p8_ CY[U
sFileName = sName; YIZ+BVa
this.nSplitter = nSpiltter; S3F8Chk5
#dEMjD
MzX4/*ba
} dWDM{t\}\
Bkh1VAT
d^W1;0
public String getSSiteURL() ml\2%07
{ 9}*<8%PSt,
return sSiteURL; lVR a{._m
} .!Qo+(
p"ElO,\
[rf.&
public void setSSiteURL(String value) hQPNxpe
{ 4o``t]
sSiteURL = value; R}J}Qb
} LktH*ePO
ne-;gTP;
f\]splL
public String getSFilePath() O;m@fS2%3
{ at5>h
return sFilePath; =}^J6+TVL
} 3qNLosm#M
# @~HpqqR
7ElU5I<S
public void setSFilePath(String value) }=T=Z#OgH
{ s%xhT
sFilePath = value; 7w?V0pLwn8
} yG..B
IqrT@jgN-
SoPiEq
public String getSFileName() "2 "gTS
{ *Tyr
return sFileName; |jT^[q(z
} Li8$Rb~q
*uG!U%jY)
kD.KZV
public void setSFileName(String value) %$Aqbd
{ |<sf:#YzY&
sFileName = value; Z[Wlyb0
} fD'/#sA#'
nz^nptw
g^1r0.Sp{8
public int getNSplitter() Z;hyi'rPJ
{ r,5-XB
return nSplitter; t)LU\!
} brntE:
: (cb2j(C
0f1H8zV
public void setNSplitter(int nCount) .>P~uZiX!
{ XTV0Le\f
nSplitter = nCount; im=5{PbJ^
} g^jJ8k,7(
} $57\u/(
z OtkC3hY
T)8p:}P!
/* H.:9:I[n
**Utility.java aVP5%
*/ /9pbnzn
package NetFox; V7:\q^$
0 sZwdO
Lx%:t YZ
public class Utility { GMBJjP&R]
EY~7oNfc`R
RK-x?ZYH'
public Utility() gwiR/(1
{ /l^y}o %?
YZ< NP
e8{^f]5
} FuuS"G,S
`y2ljIWJ
//线程睡眠 gKWzFnW
public static void sleep(int nSecond) VG)="g[%)
{ P{cos&X|
try{ -KiRj!v|
Thread.sleep(nSecond); 8"i/wMP]
} HyEa_9
catch(Exception e) ?I[h~vr6.
{ \-OC|\{32
e.printStackTrace (); Rboof`pVt
} Y%g "Y
} <(YF5Xm6$h
\45(#H<$
//日志 IcFK,y%1
public static void log(String sMsg) 9#Y2`pT
{ &DLhb90
System.err.println(sMsg); Sph*1c(R
} >)^NJ2Fd
]G*$W+G]
DWrbp
public static void log(int sMsg) >rw"Rd'
{ _R74/|
System.err.println(sMsg); 3]^'
} \f"1}f
} cy3M^_5B<
<HF-2?`
o?wt$j-
/* {y6C0A*
**TestMethod.java EwQae(PpA
*/ K]<u8eF
package NetFox; Q]#Z9H
KO&:06V{
KjOi(YUnq7
public class TestMethod { yW("G-Nm
>vVw!.fJ
X NE+(Bt
public TestMethod() e+@xsn3
{ ///xx/weblogic60b2_win.exe b_vTGl1_6
try{ jdM=SBy7q
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); k[9A,N^lZB
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); aZKXD! 4
SiteFileFetch fileFetch = new SiteFileFetch(bean); cPuHLwwYf
fileFetch.start(); CH;;V3
} 4AHL3@x
catch(Exception e){e.printStackTrace ();} C:GvP>
/{X_ .fv<v
d>!p=O`>{q
} Q2c*.Y
0S.?E.-&0
x=,8[W#XT
public static void main(String[] args) -H\,2FO
{ C[YnrI!
new TestMethod(); z-@-O
} LgHJo-+>
} yvxl_*Ds8
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