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)); ;0`IFtz
} /!N=@z)
for(int i=0;i<nEndPos.length-1;i++) cgO<%_l3`
{ c& K`t
nEndPos = nStartPos[i+1]; /&9R*xNST#
} JIsi
nEndPos[nEndPos.length-1] = nFileLength; n(i/jW~0w
} rM? J40&.
} M@Ti$=
v57<b&p26
F3tIJz>3
//启动子线程 7* [
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; N( f0,
for(int i=0;i<nStartPos.length;i++) QP<.~^ao
{ zN=s]b=/
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), yMC6 Gvp
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), c|K:oi,z
nStartPos,nEndPos,i); 2%*\XPt)
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2XEE/]^
fileSplitterFetch.start(); li{!Jp5]1b
} C{+JrHV%h
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), TM|PwY
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ?<S fhjU
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", QMy1!:Z&!
nEndPos = " + nFileLength); [7NO !^
// fileSplitterFetch[nPos.length-1].start(); ]]e>Jym
+N'&6z0Wf
Z:^ S-h
//等待子线程结束 2H`>Kj
//int count = 0; 3d,:,f|h
//是否结束while循环 #hk5z;J5
boolean breakWhile = false; Q3Y(K\
dkqyn"^
c?KIHZ0
while(!bStop) \#IKirf?
{ 3`)ej`
write_nPos(); G&t|aY-
Utility.sleep(500); 7#SfuZ0@
breakWhile = true; x&"P^gh)
p/G9P +?
5m;BL+>YE
for(int i=0;i<nStartPos.length;i++) GDb Vy)&
{ 6G}4KGQc
if(!fileSplitterFetch.bDownOver) i|xz
{ .&`apQD}
breakWhile = false; QjD=JC+
break; 1f'msy/
} 6!N2B[9
} A8o)^T(vJ
if(breakWhile) ig .
break; Ps<k2
5X9Lh_p
8'NT_NPNb
//count++; FsQoQ#*
//if(count>4) -f1lu*3\
// siteStop(); [)kuu
} +n$ruoRJh
( uG;Q
m&z(2yb1
System.err.println("文件下载结束！"); ]h=5d09z
} @= =)
catch(Exception e){e.printStackTrace ();} n&DBMU
} EXwU{Hl
owI:Qs_/4
|68u4zK
//获得文件长度 hztqZ:
public long getFileSize() w9mAeGyE
{ I$4>_D
int nFileLength = -1; 'Sesh'2 /
try{ X?;iSekI4
URL url = new URL(siteInfoBean.getSSiteURL()); 1=C<aRZ b^
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); b`%!\I
httpConnection.setRequestProperty("User-Agent","NetFox"); O1wo KkfV
jQ7-M4qO/
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int responseCode=httpConnection.getResponseCode(); fL("MDt
if(responseCode>=400) cd=K=P}p
{ rq Uk_|Xa
processErrorCode(responseCode); /0$405
return -2; //-2 represent access is error 8TK*VOf`
} gvD*^
kP5G}Bp
EziGkbpd@
String sHeader; DrbjklcUU
$o9@ ?2
WBA7G
for(int i=1;;i++) ^~6gkS }
{ G \Nnw==v
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); d @ l
//Utility.log(in.readLine()); p L^3*B.Nr
sHeader=httpConnection.getHeaderFieldKey(i); `M. I.Z_
if(sHeader!=null) k*!iUz{]
{ +@H{H2J4
if(sHeader.equals("Content-Length")) M{jq6c
{ lN0u1)'2
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 8R-;cBT
break; 5uOz#hN
} mdo$d-d&
} 4sW~7:vU
else cMoJHC,!
break; -t>"s'kv
} ]0[ot$Da6
} Plhakngj
catch(IOException e){e.printStackTrace ();} @K}h4Yok
catch(Exception e){e.printStackTrace ();} ^zS;/%
Bu+?N%CBi
L6;'V5Mg72
Utility.log(nFileLength); LGVy4D
wZW\r!Us
F?0Q AA
return nFileLength; qZ +K4H
} 4S[)5su
^4Ff8Y
x8~*+ j
//保存下载信息（文件指针位置） i[ws%GfEv
private void write_nPos() !_;J@B
{ DL,]iJm
try{ TIR Is1
output = new DataOutputStream(new FileOutputStream(tmpFile)); 12_7UWZ"
output.writeInt(nStartPos.length); 8G9( )UF.
for(int i=0;i<nStartPos.length;i++) %+<1X?;,Fq
{ }$r]\v
// output.writeLong(nPos); N93R(x)%
output.writeLong(fileSplitterFetch.nStartPos); xU6dRjYhH9
output.writeLong(fileSplitterFetch.nEndPos); yy&L&v'
} K5\l (BB
output.close(); UO!} 0'
} e$JCak=
catch(IOException e){e.printStackTrace ();} zr_L V_e
catch(Exception e){e.printStackTrace ();} &A`,hF8
} Y(2Z<d
Jf\`?g3#
(0.JoeA`y
//读取保存的下载信息（文件指针位置） R*XZPzg%
private void read_nPos() IN;9p w
{ `&xdSH
try{ }UQ,B
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); @LDs$"f9=
int nCount = input.readInt(); " vc4QH$
nStartPos = new long[nCount]; SBf=d<j 1)
nEndPos = new long[nCount]; mV)t
for(int i=0;i<nStartPos.length;i++) ;ceg:-Zqo
{ l~Ka(*[!U
nStartPos = input.readLong(); O=lRI)6w@e
nEndPos = input.readLong(); u47`&\
} ,8d&uR}x
input.close(); 4FZ/~Y1}
} H@~tJ\L
catch(IOException e){e.printStackTrace ();} gs0`nysM#
catch(Exception e){e.printStackTrace ();} $#3[Z;\
} `Mcg&Mi~
qPWf=s7!
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private void processErrorCode(int nErrorCode) &-JIXVd*R
{ -S&9"=v
System.err.println("Error Code : " + nErrorCode); a1u4v/Qu9
} mH5>50H;
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Wg,@S*x(
//停止文件下载 CdPQhv)m
public void siteStop() D%c^j9' 1
{ UQ7La 7"
bStop = true; n<<arO"cv
for(int i=0;i<nStartPos.length;i++) vv<\LN0
fileSplitterFetch.splitterStop(); p9mGiK4!
Q)qJ6-R|HD
DIWyv-
} ,j\uvi(Y
} v0tFU!Q%
//负责部分文件的抓取 dLwP7#r
**FileSplitterFetch.java qLc&.O.=
*/ 4;gw&sFF
package NetFox; ggYi7Wzsd
F MYcZ+4
rd$T6!I
import java.io.*; d(R8^v/L
import java.net.*; -vk/z+-^!
,# .12Q!
JP {`^c
public class FileSplitterFetch extends Thread { jUR* |
@H(7Mt
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String sURL; //File URL #N64ZXz_
long nStartPos; //File Snippet Start Position :,R>e}lM
long nEndPos; //File Snippet End Position :?m"kh ~
int nThreadID; //Thread's ID C=U4z|Ym
boolean bDownOver = false; //Downing is over 9f5~hBlo
boolean bStop = false; //Stop identical 1&7?f
FileAccessI fileAccessI = null; //File Access interface O:RN4/17
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l[m*csDk"
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException H1KXAy`&
{ R[fQ$` M
this.sURL = sURL; ,@f|t&
this.nStartPos = nStart; W$J.B!O
this.nEndPos = nEnd; _FS #~z'j
nThreadID = id; nU\.`.39 +
fileAccessI = new FileAccessI(sName,nStartPos);//定位 0/fZDQH
} v$(Z}Hg
[Fk|m1i!
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public void run() u(?U[pe[
{ Zu4CFX-4
while(nStartPos < nEndPos && !bStop) B,Tv9(sv
{ *-q&~
]W~M?1}
H_Sv,lwz;c
try{ P*PJ
URL url = new URL(sURL); CL-?Mi=Uc
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); qf<o"B|_9
httpConnection.setRequestProperty("User-Agent","NetFox"); '.S02=/
String sProperty = "bytes="+nStartPos+"-"; w T_l>u
httpConnection.setRequestProperty("RANGE",sProperty); 42-T&7k
Utility.log(sProperty); f(!cz,y^\*
xCT2FvX6
d/$e#8
InputStream input = httpConnection.getInputStream(); RF4B]Gqd
//logResponseHead(httpConnection); :6EX-Xyj
pmi[M)D
/~fu,2=7
byte[] b = new byte[1024]; erTly2-SJ
int nRead; 5xNOIOpDB
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) iS"6)#a72
{ I|c?*~7*
nStartPos += fileAccessI.write(b,0,nRead); 0QrRG$<4X
//if(nThreadID == 1) R3)ccom
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); JnnxXj30,
} yOb']
mRGr+m
nKtRJ,>
Utility.log("Thread " + nThreadID + " is over!"); :fy,%su
bDownOver = true; w Bm4~~_
//nPos = fileAccessI.write (b,0,nRead); p}wysVB
} X(DP=C}v9
catch(Exception e){e.printStackTrace ();} 7*Zm{r@u
} ,lFzL3'_0x
} 'X/:TOk{W
bmKvvq
k][{4~z
//打印回应的头信息 0%IZ -])
public void logResponseHead(HttpURLConnection con) bun_R-
{ /6\uBy"Xt
for(int i=1;;i++) )fS6H<*
{ EKsOj&ZiJ
String header=con.getHeaderFieldKey(i); HAs/f#zAk6
if(header!=null) 29|nt1Z
//responseHeaders.put(header,httpConnection.getHeaderField(header)); L/vw7XNrX
Utility.log(header+" : "+con.getHeaderField(header)); N#R8ez`
else GU Mf}y
break; K!E\v4
} p_apVm\t_
} f6Y-ss;'
F%%mcmHD#
4ISIg\:c*
public void splitterStop() pXh`o20I
{ I!K-* AB
bStop = true; uOKdb6]r6
} /!/Pk'p=/
\lDh"
6ZjY-)h
} MD,BGO?C
9j5Z!Vsy
A L|,\s
/* w^3S6lK
**FileAccess.java < mFUT
*//文件访问(定位，写) puEu)m^
package NetFox; n}4q2x"
import java.io.*; 9~K+h/
8hyXHe
^HI2Vp
public class FileAccessI implements Serializable{ MBQ|*}+;
YuzVh9jTI
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 >I&s%4
RandomAccessFile oSavedFile; 8Vt'X2
long nPos; |&bucG=
WBzPSnS2
L`rrT
public FileAccessI() throws IOException Sb)}
{ ~ySsv
this("",0); ZR{YpLFQ
} j``Ku@/x0
8S[bt@v
b!"FM/%
public FileAccessI(String sName,long nPos) throws IOException !)}z{,Jx
{ cN\_1
oSavedFile = new RandomAccessFile(sName,"rw"); 7s}F`fjKP
this.nPos = nPos; 1h)K3cC
oSavedFile.seek(nPos); %Z*)<[cIE0
} v&f\ Jv7
wg:\$_Og
v9t'CMU
public synchronized int write(byte[] b,int nStart,int nLen) @bnw$U`+
{ &{q'$oF
int n = -1; C!^;%VQ}d
try{ =i/r:
oSavedFile.write(b,nStart,nLen); %?S[{ 4A&
n = nLen; v+<4?]EJ
} sdgI ,
catch(IOException e) *r!qxiY= r
{ 3z"%ht~;
e.printStackTrace (); Sj8fo^K50
} aan(69=jz
p}X *HJq$
5,Co(K
return n; AF{@lDa1h
} RyWfoLc
jD6T2K7i
+p]@b
} 'S=eW_ 0/
4>Nig.#
: 'pK
/* W(.svJUgb.
**SiteInfoBean.java }C~9?Y
*/ rvb@4-i>iI
package NetFox; |H5$VSw
Z 2$S'}F
MY(51)*
public class SiteInfoBean { Jt?`(H
|Fq\%y#
0p\Kf(|E*6
private String sSiteURL; //Site's URL IZd~Am3f
private String sFilePath; //Saved File's Path scrss
private String sFileName; //Saved File's Name izu_KBzy
private int nSplitter; //Count of Splited Downloading File rDc$#
c/(Dg$DbX
(8/&
public SiteInfoBean() -Gm}i8;
{//nSplitter的缺省值为5 f67pvyy -
//default value of nSplitter is 5 %PK(Z*>
this("","","",5); :e}j$vF
} 7sVO?:bj}
P(LiH
0]GenT"
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ;YBk.} %
{ 9h6siK(F
sSiteURL= sURL; `vf]C'
sFilePath = sPath; )E6E}
sFileName = sName; ^Q!A4qOQ
this.nSplitter = nSpiltter; &u(pBr8B
91k-os(4]
h6tYy_(G
} tC7 4=
=>GGeEL
`2q]ju
public String getSSiteURL() &m TYMpA
{ $]^Io)}f@
return sSiteURL; ~P*{%=a
} Ve40H6Ox
]2iEi`"[
SxX
public void setSSiteURL(String value) _0Y?(}
{ #aKUD
sSiteURL = value; @CC 6`D
} Y{X%C\
_) UnHp_^
j`MK\*qmz
public String getSFilePath() [Z!oVSCZD%
{ Z)}2bJwA
return sFilePath; 0}g~69Z1=
} T?7++mcA
t\n'Kuk`
D\pX@Sx,v[
public void setSFilePath(String value) V7 hO}
{ t ^1uj:vD
sFilePath = value; (:}}p}u
} X0LC:0+
: TqeVf
X*&Thmee
public String getSFileName() 9]I{GyH
{ mCQ:<#
return sFileName; }%0X7'
} _gl1Qtv@rf
9LOq*0L_:
hF5(1s}e$
public void setSFileName(String value) LK>;\BRe?
{ TT&%[A+
sFileName = value; d?/>Qqw:#
} SPtx_+ Q)S
K4OiKYq
Mh@n>+IR
public int getNSplitter() LeNSjxB
{ z<9Llew^e
return nSplitter; '7.4!I0'
} +IlQZwm~
-<(RYMk*)
df&.!7_R`
public void setNSplitter(int nCount) gy"<[N .?c
{ 8,&Y\b`..
nSplitter = nCount; C8} ;,
} |vxmgX)
} nB4+*=$E+-
#jPn7
caV DV
/* OLqynY
**Utility.java ^szi[Cj
*/ 9H+Q/Q*-a
package NetFox; }|Bs|$q
g3(LDqB'.
^^*Ia'9
public class Utility { ZM[Z9/S8
ciFqj3JS
0(o.[%Ye
public Utility() h]j>S
{ ;f} ']2
!mUO/6Q hq
4AKPS&k;
} 6wZ)GLW[
eAG)+b
//线程睡眠 $\PU Y8
public static void sleep(int nSecond) \(r$f!`
{ ;{v2s;
try{ #J
Thread.sleep(nSecond); f|~X}R
} b|\dHi2FT
catch(Exception e) bo@, B
{ z8xBq%97us
e.printStackTrace (); Wmx3@]<
} +M<W8KF
} 'c3'eJ0
8fPTxvXqL
//日志 2W#^^4^+
public static void log(String sMsg) SnM^T(gtS3
{ O9AFQ)u
System.err.println(sMsg); Ep3I*bQ Y
} aS~~*UHW
5gb:,+
uJ0Wb$%
public static void log(int sMsg) }^^c/w_
{ WADEDl&,'
System.err.println(sMsg); js%n]$N
} 0;hn;(V]"
} QXgfjo
u^W!$OfZpp
Fqh./@o
/* (B!DBnq
**TestMethod.java <-,y0Y'
*/ Q2F20b
package NetFox; z:1t vG
zV(aw~CbZ
F_4Et
public class TestMethod { _/Ay$l;F
`g0^W/j
k(_OhV_
public TestMethod() DhD##5a
{ ///xx/weblogic60b2_win.exe <5}j(jxz}
try{ }c>vk
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Hx!eCTO:*
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 7U2B=]<e-
SiteFileFetch fileFetch = new SiteFileFetch(bean); U} w@,6
fileFetch.start(); s_e*jM1
} ^)C#
catch(Exception e){e.printStackTrace ();} ew]G@66
7nP{a"4_
y9w,Su2
} }w8yYI
NQqNBI?cr
`,4@;j<^@
public static void main(String[] args) Bx6,U4o*
{ '`f+QP=`
new TestMethod(); C &y 2I
} m_,Jbf
} cvhwd\
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