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)); vCj4;P g
} zVdKYs i^
for(int i=0;i<nEndPos.length-1;i++) 45)D+
{ !N1J@LT5h
nEndPos = nStartPos[i+1]; 6}ftBmv
} 3T1P$E" m
nEndPos[nEndPos.length-1] = nFileLength; @ u+|=x];
} .a:Z!KF
} Pu..NPl+
3p_b8K_bG
g2=}G<*0
//启动子线程 KaW~ERx5
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ,E?4f @|X
for(int i=0;i<nStartPos.length;i++) \!<"7=(J{4
{ E_3r[1l
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), |'<vrn
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 5mavcle{4r
nStartPos,nEndPos,i); 1"O&40l
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); hM>*a!)U
fileSplitterFetch.start(); 4UD' %}>y
} {2:d`fqD
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 4fty~0i=z
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); g/#~N~&
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", ~^$MA$/p
nEndPos = " + nFileLength); vLDi ;
// fileSplitterFetch[nPos.length-1].start(); U Du~2%
-NzTqLBn
mgVML&^
//等待子线程结束 K_#UZA< Y
//int count = 0; B\[-fq
//是否结束while循环 dE [Ol
boolean breakWhile = false; &XQZs`41+
#ZWl=z5aBi
dIJGB==
while(!bStop) -k{Jp/-D
{ q- :4=vkn
write_nPos(); zMGzReJ
Utility.sleep(500); 0`n 5x0R
breakWhile = true; 7Z0/(V.-
WNF9#oN|oT
DA=1KaJ.
for(int i=0;i<nStartPos.length;i++) M&yqfb[
{ gz61FW
if(!fileSplitterFetch.bDownOver) W:O0}
{ cPuHLwwYf
breakWhile = false; |I^y0Q:K
break; ET-Vm >]
} [Oy >R
} Y<Q\d[3^F
if(breakWhile) zvr\36
break; h8=h >W-
/U*yw5
WZ?!!
//count++; `?uPn~,e8
//if(count>4) C[YnrI!
// siteStop(); J]fS({(\I
} 1;Xgc@
GMm'of#
2Va4i7"X\
System.err.println("文件下载结束！"); uTGcQs}
} Dp^/gL=
catch(Exception e){e.printStackTrace ();} 54q3R`y
} 8=Q VN_
Y6ben7j%-
wiE]z
//获得文件长度 yd>}wHt
public long getFileSize() ?/d!R]3
{ wL2XNdo}<
int nFileLength = -1; D1Yh,P<CF\
try{ -t4 [oB
URL url = new URL(siteInfoBean.getSSiteURL()); e<5Y94YE
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); [/ohk&
httpConnection.setRequestProperty("User-Agent","NetFox"); *48IF33&s
SRCOs1(EK9
%&<W(|U1<
int responseCode=httpConnection.getResponseCode(); 4*M@]J "
if(responseCode>=400) p4wr`"Zz
{ V`k8j-*s
processErrorCode(responseCode); r7I B{}>-
return -2; //-2 represent access is error m:{tgcE
} 9+Nw/eszO
(F8AL6
{oWsh)[x2
String sHeader; c_1/W{
mP-2s;q
Y {c5
for(int i=1;;i++) <xn;bp[
{ de YyaV
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); aws"3O% uW
//Utility.log(in.readLine()); .7Kk2Y
sHeader=httpConnection.getHeaderFieldKey(i); &iSD/W
if(sHeader!=null) Nn#u%xvJt
{ jTSOnF}C~+
if(sHeader.equals("Content-Length")) l2&hBacT
{ &qRJceT(
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ~m`!;rE
break; V8"Wpl9Cz
} 0YS?=oi
} QIV%6q+*R
else h^M^7S
break; [rdsv
} 5I,$EGG
} Ze ? g
catch(IOException e){e.printStackTrace ();} 0ar=cuDm
catch(Exception e){e.printStackTrace ();} |F!F{d^p
E _iO@
mU G %LM
Utility.log(nFileLength); 8QF`,oXQO
gb 4pN
nGrVw&
return nFileLength; ;nB2o-%
} bPd-D-R
-7`-wu
Sz0+<F#5
//保存下载信息（文件指针位置） .nZ3kT`
private void write_nPos() 9?`RR/w
{ O9]\Q@M.
try{ LSkk;)'2K
output = new DataOutputStream(new FileOutputStream(tmpFile)); XDLEVSly7
output.writeInt(nStartPos.length); xl] ;*&
for(int i=0;i<nStartPos.length;i++) -G b-^G
{ ?~F. /
// output.writeLong(nPos); 9L)L|4A.l
output.writeLong(fileSplitterFetch.nStartPos); MF.[8Zb
output.writeLong(fileSplitterFetch.nEndPos); T;?+kC3
} K.DXJ UR
output.close(); WC-_+9)2&
} n33kb/q*
catch(IOException e){e.printStackTrace ();} t ;-L{`mW
catch(Exception e){e.printStackTrace ();} a8s4T$
} b!a %YLL
^M Ey,
nGa1a
//读取保存的下载信息（文件指针位置） T1NH eH>
private void read_nPos() v>-YuS
{ F?4Sz#
try{ ;^-:b(E
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); [7\>"v6
int nCount = input.readInt(); e4.&aIC[
nStartPos = new long[nCount]; 6 =gp:I
nEndPos = new long[nCount]; Hg(5S,O2
for(int i=0;i<nStartPos.length;i++) y\[r(4h
{ JO1 ,TtA
nStartPos = input.readLong(); Ew4g'A:H
nEndPos = input.readLong(); x9V {R9_gf
} 5py R~+
input.close(); KQ)T(mIqp
} 8(A{;9^g
catch(IOException e){e.printStackTrace ();} uO'/|[`8
catch(Exception e){e.printStackTrace ();} _413\`%8?
} xzk}[3P{
z="L4
$D_HZ"ytu
private void processErrorCode(int nErrorCode) JR1*|u
{ uva\0q
System.err.println("Error Code : " + nErrorCode); E`)Qs[?Gk
} dlD}Ub
:p-Y7CSSu
iJP{|-h
//停止文件下载 Z"tQpJg
public void siteStop() qrDcL>Hrn
{ f\}22}/
bStop = true; pFIecca w
for(int i=0;i<nStartPos.length;i++) 1xTTJyoq
fileSplitterFetch.splitterStop(); YIOR$
gX*K&*q
gaeOgP.0
} J}@GKNm
} %h+uD^^$
//负责部分文件的抓取 +X^4; &
**FileSplitterFetch.java MY F#A
*/ LK+felL
package NetFox; _A-V@%3
6%?A>
{tt$w>X
import java.io.*; ~ hm`uP
import java.net.*; qG9qN.|dC
D#v?gPo4
oVkr3KZ
public class FileSplitterFetch extends Thread { p>p'.#M
A,c'g}:
*Nlu5(z
String sURL; //File URL %dmfBf Ev
long nStartPos; //File Snippet Start Position ;$;rD0i|
long nEndPos; //File Snippet End Position u^=@DO'
int nThreadID; //Thread's ID c]v +
boolean bDownOver = false; //Downing is over N!m%~kS9k<
boolean bStop = false; //Stop identical hTTfJDF
FileAccessI fileAccessI = null; //File Access interface 3;y_mg
Dl\d_:+
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException x,1=D~L}
{ kfCKhx
this.sURL = sURL; !K\itOEP-
this.nStartPos = nStart; t w!.%_1^
this.nEndPos = nEnd; -S$$/sR
nThreadID = id; h5!d
fileAccessI = new FileAccessI(sName,nStartPos);//定位 -f.R#J$2
} (C\r&N
}ecsGw
`M rBav
public void run() XU-*[\K
{ ~:Ixmqi}R
while(nStartPos < nEndPos && !bStop) q?iCc c
{ ;[~^(. f
q{@P+2<wF
.. UoyBV
try{ \HG$V>2
URL url = new URL(sURL); >0V0i%inmF
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); F[`vH
httpConnection.setRequestProperty("User-Agent","NetFox"); M.[wKGX(
String sProperty = "bytes="+nStartPos+"-"; d h?dO`
httpConnection.setRequestProperty("RANGE",sProperty); KpGUq0d@
Utility.log(sProperty); *(nJX.7
M5u_2;3
i;]CL[#2e`
InputStream input = httpConnection.getInputStream(); -yA3 RP
//logResponseHead(httpConnection); ;^ov~PPl
YkI9d&ib+
5Hy3\_ +
byte[] b = new byte[1024]; nNs .,J)
int nRead; QQ~23TlA
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) O+vcs4
{ mt^`1ekoY
nStartPos += fileAccessI.write(b,0,nRead); |hD~6a
//if(nThreadID == 1) en%B>]QI
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); hiIyaWU
} ?OO%5PSen
k-vA#
BPiiexTV9
Utility.log("Thread " + nThreadID + " is over!"); UAKu_RO6S
bDownOver = true; 6lZGcRO
//nPos = fileAccessI.write (b,0,nRead); Z+,CL/
} j%u8=
catch(Exception e){e.printStackTrace ();} ?V?<E=13
} ) H+d.Y
} 6Wb!J>93
)r pD2H
F;W'
//打印回应的头信息 (QKsB3X
public void logResponseHead(HttpURLConnection con) FSe5k5
{ My],6va^
for(int i=1;;i++) ?#i|>MRR>
{ v!KJ|c@m
String header=con.getHeaderFieldKey(i); aC}p^Nkr"k
if(header!=null) X7b!;%3@
//responseHeaders.put(header,httpConnection.getHeaderField(header)); }EP|Mb
Utility.log(header+" : "+con.getHeaderField(header)); %2,/jhHL
else $i -zMa
break; w#rVSSXQ3
} d96fjj~
} $-e=tWkgv
~9bv Wd1D
xlk5Gob*
public void splitterStop() ;8uHRcdQ
{ A`g.[7
bStop = true; -FaaFw:Z;A
} {H'X)n$
5DUi4 Cbgy
qNy-o\;XN
} 8,H~4Ce3
w7r'SCVh3+
1Lc8fP$
/* 8M~u_`6
**FileAccess.java vU7&'ca
*//文件访问(定位，写) EFeAr@nj
package NetFox; A^t"MYX@
import java.io.*; R7,pukK
UL[uh@4
kM,@[V
public class FileAccessI implements Serializable{ n}f3Vrl
`{Hb2 }L5
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 C!hXEtK
RandomAccessFile oSavedFile; d;<.;Od$`
long nPos; |Cu1uwy
!*9FKDB{
yZ?$8r
public FileAccessI() throws IOException x!>d 6lgej
{ u!M&;QL
this("",0); "7:u0p!
} KjC[q
["<5?!bU
X:DMT>5k
public FileAccessI(String sName,long nPos) throws IOException @f\ X4!e*y
{ :bI,rEW#_
oSavedFile = new RandomAccessFile(sName,"rw"); " xlJs93c
this.nPos = nPos; M.X}K7Z_/
oSavedFile.seek(nPos); lu3Q,W
} p?}&)Un
t6j-?c('
` 4OMZMq
public synchronized int write(byte[] b,int nStart,int nLen) p0
{ $4sAnu]
int n = -1; 80dSQ"y
try{ tD865gi
oSavedFile.write(b,nStart,nLen); N=.}h\{0
n = nLen; >}mNi:6xq
} z_'dRw
catch(IOException e) \G]K,TG
{ bKTqX[=
e.printStackTrace (); Sio1Q0
} ykJ+%gla
zI(xSX@
,#=eu85'
return n; SCqu,
} x,}ez
}klE0<W|5\
dBsRm{aS
} *sjj"^'=
F|DR
<Sz>ZIISd
/* !."Izz/
**SiteInfoBean.java ]r"31.w(
*/ ~GAlNIv]
package NetFox; h<+PP]l=
#($k 3OA
oXnC"y}0P
public class SiteInfoBean { 5w]DncdQ~
&19lk
LZgwIMd
private String sSiteURL; //Site's URL y>DfM5>
private String sFilePath; //Saved File's Path l~`txe
private String sFileName; //Saved File's Name 38Bnf
private int nSplitter; //Count of Splited Downloading File 4x=V|"
Pn~pej5'K
8XLxT(YFIs
public SiteInfoBean() MtMvpHk
{//nSplitter的缺省值为5 xC= y^- 1
//default value of nSplitter is 5 Y{+zg9L*
this("","","",5); em f0sL
} ;D%$Eh&oma
LsuAOB 8
!l sy&6
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Oz"@yL}
{ e-L5=B
sSiteURL= sURL; 67Af} >Q
sFilePath = sPath; c#]'#+aH
sFileName = sName; SSl8
this.nSplitter = nSpiltter; ]2hF!{wc
RTdD]pE8Q
2hjre3"?
} x@{G(W:W
'w>uFg1.
DLwC5Iir
public String getSSiteURL() <~IH`
{ 0X] ekq
return sSiteURL; dSA [3V
} .WN;TjEg!
I!C(K^
WLg6-@kxXs
public void setSSiteURL(String value) -o=P85V
{ ]# tGT0
sSiteURL = value; $Uv<LVd(
} ]be0I)
gJ)h9e*m^
'sT}DX(7M
public String getSFilePath() /K2.V@T
{ ;o~+2Fir
return sFilePath; ~frPV8^DP
} `dG.L
<>&e/
(%ri#r
public void setSFilePath(String value) r'mnkg2,
{ _qO;{%r
sFilePath = value; orcZyYU
} /-G qG)PX
!`O_VV`/@
G#9o?
public String getSFileName() }J'5EAp
{ >#"jfjDuR
return sFileName; #cSw"A
} {2'74
j. ks UJ
ims=-1,
public void setSFileName(String value) &vJ(P!2f<
{ fl5UY$a2-
sFileName = value; YW4bm
} _{2Fx[m%
T@d_t
!}Woo$#ND
public int getNSplitter() *pS7/Qe
{ R:pBbA7E
return nSplitter; qH{8n`
} -Y 6.?z
8JjU 9#
^t/'dfF
public void setNSplitter(int nCount) _.Z&<.lJ
{ <'o'H
nSplitter = nCount; A .jp<>
} \gJapx(
} Hb@G*L$
4$q)e<-
_x,-d|9bd
/* NbQMWU~7
**Utility.java rH2tC=%
*/ C>k;MvqO
package NetFox; tLoD"/z
+hyWo]nW0
yp^[]Mz=
public class Utility { .JD4gF2N
mER8> <
VFO&)E/-
public Utility() pdcwq~4~%
{ CL<KBmW7
,XBV}y
Dbkuh!R
} sBuq
SG+i\yu$h0
//线程睡眠 2=!3[> B
public static void sleep(int nSecond) 0c\|S>g[
{ !mErt2UJl
try{ P98X[0&
Thread.sleep(nSecond); -UD~>s
} NZ%~n:/V#
catch(Exception e) ?V\9,BTb)
{ KHc/x8^9
e.printStackTrace (); "[".3V
} }G,SqpcG
} tsSS31cv
eN2k8=
//日志 5>4A}hSe
public static void log(String sMsg) 3q.[-.q
{ .olPm3MC
System.err.println(sMsg); z7.C\l
} v{rK_jq
MLv.v&@S
VT.{[Kl
public static void log(int sMsg) 8H%I|fm
{ asmW W8lz
System.err.println(sMsg); abJ@>7V
} 3qxG?G N
} jFPE>F7-M
J:mu%N`
G &rYz
/* 4f*Ua`E_
**TestMethod.java p$b=r+1f
*/ thm3JfQt
package NetFox; 3Ld ;zW
+{Vwz
sKB-7
public class TestMethod { amk42
,TfI
{,-5k.P[
public TestMethod() M:1F@\<
{ ///xx/weblogic60b2_win.exe sWZtbW;)
try{ jO3u]5}.6
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); T>uWf#&pjs
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 7p>-oR"
SiteFileFetch fileFetch = new SiteFileFetch(bean); %6c*dy
fileFetch.start(); +VpE-X=T
} @IyH(J],h
catch(Exception e){e.printStackTrace ();} }^Ua
<{z3p:\
6t mNfI34
} _F/lY\vm
v YmtpKNj%
aa YQ<
public static void main(String[] args) 8yo6v3JqC
{ o|*|
new TestMethod(); m9<[bEO<$
} 7s fuju(
} U0bEB
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