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)); iZ2|/hnw
} &S9Sl
for(int i=0;i<nEndPos.length-1;i++) 9cud CF
{ zz3Rld!b[
nEndPos = nStartPos[i+1]; _3-nw
} V6Ie\+@.\
nEndPos[nEndPos.length-1] = nFileLength; U`sybtuBP'
} hK*:pf
} z8FeL5.(
yg\bCvL&
=7pLU+ u
//启动子线程 FI{9k(
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ,5Jq ZD
for(int i=0;i<nStartPos.length;i++) &PWz4hZ
{ k/hE68<6i
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), A$.woE@
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), [xq"[*Evv
nStartPos,nEndPos,i); &(3kwdI
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); }6b=2Z}
fileSplitterFetch.start(); 1wSJw
} /M(FuV
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ORk8^0\
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); p>7!"RF:U
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", *#{[9d
nEndPos = " + nFileLength); kb{h`
// fileSplitterFetch[nPos.length-1].start(); 67Rsd2
% FW__SN$c
rld4uy}m
//等待子线程结束 X'4e)E3*O
//int count = 0; ,":_=Tf.
//是否结束while循环 HV ab14}E
boolean breakWhile = false; 'p,QI>
'aMT^w4if)
I@~hz%'
while(!bStop) s,>1n0a
{ Z'p7I}-qr
write_nPos(); } <; y,4f
Utility.sleep(500); *kE2d{h^=C
breakWhile = true; S*~v9+
G m40u/
l@7Xgsey
for(int i=0;i<nStartPos.length;i++) SFAh(+t
{ @bU(z$eB
if(!fileSplitterFetch.bDownOver) [Dd?c,5AD
{ 95jJ"4a+
breakWhile = false; kuq3QW<
break; o!EPF-:
} } _Yk.@J5
} {tn%HK">
if(breakWhile) .6S]\dp7~
break; NY(c4fzl
zB`)\
e{@TR x
//count++; H~x,\|l#
//if(count>4) qYZ\<h^
// siteStop(); j;@7V4'
} l<0BMwS8
LQ pUyqR
*+TIF"|1
System.err.println("文件下载结束！"); U&#1qRm\h
} +*-u_L\'
catch(Exception e){e.printStackTrace ();} Q?rb(u(
} (:W=8G,p
-N+'+
w.exLC
//获得文件长度 HT7V} UiaO
public long getFileSize() C(7uvQ
{ xb$eFiQ
int nFileLength = -1; +V*FFv
try{ Q)x`'[3"7W
URL url = new URL(siteInfoBean.getSSiteURL()); ^pA|ubZ
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); TUzpln
httpConnection.setRequestProperty("User-Agent","NetFox"); vy\;#X!
-ZqN~5>j)
*fVs|
int responseCode=httpConnection.getResponseCode(); ~yz7/?A)TS
if(responseCode>=400) -#T?C]}
{ I;kKY
processErrorCode(responseCode); is_`UDaB
return -2; //-2 represent access is error f.rc~UI?
} qYLOq`<f
44_7gOZ
bj^YB,iSM
String sHeader; zOkUR9
vG9A'R'P
<EKDP>,~
for(int i=1;;i++) X?5M)MP+I
{ 1MV\Jm
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ilL] pU-
//Utility.log(in.readLine()); A`2l;MW
sHeader=httpConnection.getHeaderFieldKey(i); ~9#[\/;"
if(sHeader!=null) 9Cbf[\J!bq
{ aLapb5VV
if(sHeader.equals("Content-Length")) l%]S7|PKx
{ %Z?2.)
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); zM?JLNs]<{
break; Vh1{8'GQ
} Dn;6O
} 8;>vgD
else Fa78yY+6
break; #MYhKySku
} !7XAc,y
} Z!o&};_j
catch(IOException e){e.printStackTrace ();} \9*wo9cV
catch(Exception e){e.printStackTrace ();} \A'MEd-
Enr8"+.(
hQ`g B.DR
Utility.log(nFileLength); M;*f(JY$
{2?o:
qv|geBW
return nFileLength; 7N0V`&}T
} .} <$2.
J5PXmL
aV3:wp]Gn
//保存下载信息（文件指针位置） NFpR jC?
private void write_nPos() ~*R"WiDtI
{ iW\cLp "
try{ <}x_F)E[t
output = new DataOutputStream(new FileOutputStream(tmpFile)); eglcf z%
output.writeInt(nStartPos.length); A+i|zo5p=k
for(int i=0;i<nStartPos.length;i++) :/'2@M
{ 3n-~+2l
// output.writeLong(nPos); 9fR`un)f}
output.writeLong(fileSplitterFetch.nStartPos); y\7 -!
output.writeLong(fileSplitterFetch.nEndPos); vL~nJv
} - `^594
output.close(); ]H8,}
} j8kax/*[
catch(IOException e){e.printStackTrace ();} MzLnD D^
catch(Exception e){e.printStackTrace ();} W]cJP
} lrg3n[y-l
?.66B9Lld
p%A s6.
//读取保存的下载信息（文件指针位置） Zhb)n
private void read_nPos() F8{"Rk}
{ :[f2iZ"
try{ wRu+:<o^.
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); R5=2EwrGP
int nCount = input.readInt(); A?I/[zkc
nStartPos = new long[nCount]; ,YzrqVY
nEndPos = new long[nCount]; )`5kfj
for(int i=0;i<nStartPos.length;i++) YSi[s*.G
{ YB{hQ<W
nStartPos = input.readLong(); a~>.
nEndPos = input.readLong(); rMkoE7n
} !#P|2>>u
input.close(); t,|`#6Ft
} _kR);\V.8
catch(IOException e){e.printStackTrace ();} yxq+<A4,a
catch(Exception e){e.printStackTrace ();} .9X,)^D
} &c<0g`x
a?#v,4t^
!qe,&JL
private void processErrorCode(int nErrorCode) aq/'2U 7
{ tHgn-Dhzr
System.err.println("Error Code : " + nErrorCode); ge*(w{|x
} +RLHe]9&
\[</|]'[
#4uuT?!
//停止文件下载 Sb@:ercC,
public void siteStop() xW92ZuzSH
{ ?2h)w=dO
bStop = true; D=*3Xd
for(int i=0;i<nStartPos.length;i++) /~`4a
fileSplitterFetch.splitterStop(); }T([gc7~
Fljqh8c5
VNKtJmt
} @64PdM!L
} 20glz(
//负责部分文件的抓取 t# cm|
**FileSplitterFetch.java .ET@J`"M
*/ $kPC"!X\
package NetFox; >|h$d:~n
8BP.VxX
Ak(_![Q:q\
import java.io.*; .{,PC
import java.net.*; yTj!(C
.Y!]{c
p'PHBb8I
public class FileSplitterFetch extends Thread { aH6{_eY
]ADj9
Y![m'q}K
String sURL; //File URL d8l T+MS=
long nStartPos; //File Snippet Start Position $ {29[hO
long nEndPos; //File Snippet End Position |ymw])L
int nThreadID; //Thread's ID ke$g[g
boolean bDownOver = false; //Downing is over t[>y=89
boolean bStop = false; //Stop identical 1+`Bli]dE
FileAccessI fileAccessI = null; //File Access interface fZM)>
|l5ol@2*
W$_}lE$
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException <Z^P8nu
{ [,;h1m ~iX
this.sURL = sURL; fB.xjp?
this.nStartPos = nStart; ~zdHJ8tYp
this.nEndPos = nEnd; $$my,:nH
nThreadID = id; <_X`D4g]XO
fileAccessI = new FileAccessI(sName,nStartPos);//定位 !V|%n(O"
} FdrH,
5}J|YKyP
34k}7k~n
public void run() g5THkxp
{ cBxBIC
while(nStartPos < nEndPos && !bStop) /]pBcb|<
{ .Pz( 0Y
x\/N09
px`o.%`'
try{ 9ure:Dko(Y
URL url = new URL(sURL); j,@N0~D5
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); []opPQ 1
httpConnection.setRequestProperty("User-Agent","NetFox"); Vaj4p""\F
String sProperty = "bytes="+nStartPos+"-"; a~#MMl
httpConnection.setRequestProperty("RANGE",sProperty); ci]IH]x
Utility.log(sProperty); 6$42-a%b
cL/6p0S
fb8"hO]s
InputStream input = httpConnection.getInputStream(); +n#kpi'T
//logResponseHead(httpConnection); QL_~E;U
{@XzY>
(?luV#{5
byte[] b = new byte[1024]; vAeh#V~#
int nRead; ]#)1(ZE
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) RPH]@
{ Ps<6kQ(
nStartPos += fileAccessI.write(b,0,nRead); !Db0r/_:G
//if(nThreadID == 1) -Fi{[%&u
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); _FV<[x,nE8
} )`Zj:^bz9
Jxyeh1zqB
w QV4[
Utility.log("Thread " + nThreadID + " is over!"); 0}(ZW~&1
bDownOver = true; [=Qv?am
//nPos = fileAccessI.write (b,0,nRead); v4X\LsOP
} ZHA6BVVT
catch(Exception e){e.printStackTrace ();} `gI`Cq4
} <Q-Y$ ^\
} *{3&?pxx
hYm$Sx(=
] qT\z<}
//打印回应的头信息 ohI>\
public void logResponseHead(HttpURLConnection con) WD"3W)!
{ 5f.G^A: _X
for(int i=1;;i++) )e,Rp\fY$
{ m6V:x/'=
String header=con.getHeaderFieldKey(i); *hJ&7w ~
if(header!=null) l`#XB:#U
//responseHeaders.put(header,httpConnection.getHeaderField(header)); z:Sr@!DZ
Utility.log(header+" : "+con.getHeaderField(header)); %cy]dEL7
else b{:c0z<
break; z:m`
} UkO L7M
} 4Ji6B)B
ym>>5(bni
XaFu(Xu7
public void splitterStop() >.P/fnvJ
{ mFL"h
bStop = true; {Ac5(li_
} @fDWp/
;.%Ii w&WG
1J(` kQ)c
} B.zRDB}i=
>Ln/)j
?]JTrv"zp
/* [^iQE
**FileAccess.java 6\8 lx|w
*//文件访问(定位，写) s)?=4zJ
package NetFox; J;?#Zt]`L
import java.io.*; <r[5 S5y
AOh\%|}
aT v
public class FileAccessI implements Serializable{ Y[oNg>Rz
{9yv3[f3
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 T]&% KQ
RandomAccessFile oSavedFile; (:JX;<-
long nPos; Pfy2PpA
|AY`OVgcKD
C26vH#C
public FileAccessI() throws IOException NGA8JV/U
{ !/1aot^(
this("",0); *'b3Z3c,;
} &&(^;+
v]"W.<B,
_?9|0>]xG
public FileAccessI(String sName,long nPos) throws IOException m@|0iDS
{ Y)X 'hk)5|
oSavedFile = new RandomAccessFile(sName,"rw"); vr/O%mDp
this.nPos = nPos; )qgcz<p?W
oSavedFile.seek(nPos); ^qn,b/>L
} iL^bf*
B@v\tpR
i{#5=np H
public synchronized int write(byte[] b,int nStart,int nLen) ^jY'Hj.Bs
{ RnvPqNs
int n = -1; oCl $ 0x
try{ QkEIV<T&)l
oSavedFile.write(b,nStart,nLen); FXpI-?#E<
n = nLen; 'qhi8=*
} \I!C`@0
catch(IOException e) [M:ag_rm+f
{ Z0Tpz2m
e.printStackTrace (); m)5,ut/
} jRk"#:
m :6.
J(k\Pz*
return n; /dT7:x*
} br@GnjG
\O*8%
XI4le=^EM
} *]L(,_:"
)#^5$5
v/W\k.?q/
/* .7h:/d Y:
**SiteInfoBean.java 7Ya4>*B
*/ Ya%-/u
package NetFox; 3WOm`<
#FAy ]7/O
/S}4J"
public class SiteInfoBean { R2]2#3`
jH4,-
9n(.v}
private String sSiteURL; //Site's URL k<bA\5K
private String sFilePath; //Saved File's Path .ZV-]jgr
private String sFileName; //Saved File's Name AW;ncx;
private int nSplitter; //Count of Splited Downloading File =Nyq1~
j_3X 1w)k
mes/gqrJ1I
public SiteInfoBean() V30Om3C
{//nSplitter的缺省值为5 w=dTa5
//default value of nSplitter is 5 KdBE[A-1^M
this("","","",5); EWcqMD]4u
} x]e&G!|
Bl\/q83(
B)q 5m y
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 676r0`
{ vlygS(Y_7
sSiteURL= sURL; X9|={ng)g#
sFilePath = sPath; +,"O#`sy<
sFileName = sName; S:.Vt&+NJ
this.nSplitter = nSpiltter; <)f1skJsP
-&AgjzN!
m$ubxI)
} !Zr 9t|_
@X$~{Vp__
DdI V~CxD
public String getSSiteURL() J)*7JX
{ E41ay:duAl
return sSiteURL; )~u<u:N
} RotWMGNK
/Dmuvb|A
lk<}`#(g
public void setSSiteURL(String value) !=-{$& {
{ fz9 ,p;b
sSiteURL = value; vtm?x,h
} q6A"+w,N
:1O49g3R
h(<2{%j
public String getSFilePath() xcVF0%wVC
{ JB}jt)ol%
return sFilePath; =>y%Aj&4
} ;5ANw"Dq
vVA)x~^
:n%KHen3\
public void setSFilePath(String value) a 8(mU%
{ +NM`y=@@
sFilePath = value; 3Z taj^v
} )2&U Rt.
['`Vg=O.{
h'wI
public String getSFileName() JBvMe H5
{ [ST,/<?0
return sFileName; KF.d:
} BEfP#h=hr
y)Y0SY1\j
q'% cVM
public void setSFileName(String value) `A\|qH5`W
{ D^!x@I~:
sFileName = value; <kc9KE
} /x2MW5H
dXBXV>rbB
,`su0P\%#.
public int getNSplitter() hFiJHV
{ <,X?+hr
return nSplitter; '1f:8
} v}>5!*
1OwVb
d[t+iBP;)
public void setNSplitter(int nCount) 4u.v7r
{ Gc1!')g!
nSplitter = nCount; i& phko}
} 0|L%)'F
} a6/$}lCq
SI~MTUqt
:wcv,YoSG
/* b-Uy&+:X*d
**Utility.java Ra~|;( %d
*/ l`V^d
package NetFox; 6M)4v{F
Y \oz9tf8
$HE ?B{
public class Utility { ;bh[TmQTJ
exfJm'R?n
Mu>WS)1lS
public Utility() E$?:^ausu
{ QV_e6r1t#m
$,&3:ke1
T=-$ok`G
} V]fsjpvlmr
)RZ:\:c
//线程睡眠 .~L^h/)Gjy
public static void sleep(int nSecond) 'UN 'gXny
{ 08pG)_L
try{ ?A\[EI^
Thread.sleep(nSecond); O.+02C_*
} |."thTO
catch(Exception e) u,f$cR
{ 9-6E(D-ux
e.printStackTrace (); rf[w&~R
} NMCMY<o
} oDvE0"Sz
#sg^l>/*
//日志 +. ` I
public static void log(String sMsg) _=s{,t &u
{ ^CtA@4
System.err.println(sMsg); Dg_AoC
} XSDudL
Qjl.O HO
-NgL4?p=
public static void log(int sMsg) Jd0I!L
{ `dpm{sn
System.err.println(sMsg); ]!=,8dY
} N-Jp; D
} {WYHT6Z
9}_ccq
,f(:i^iz!
/* fZ6"DJZ
**TestMethod.java $^XCI%DH
*/ P+j5_V{\b
package NetFox; LaolAqU
pMy];9SvW
@9X+ BdQU
public class TestMethod { x_K8Gr#Z0
+uD4$Wt_F
ivb?B,Lz0
public TestMethod() q0a8=o"|
{ ///xx/weblogic60b2_win.exe ),u)#`.l G
try{ D+u#!t[q
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 4sCzUvI~Y1
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); `uN}mC!r]
SiteFileFetch fileFetch = new SiteFileFetch(bean); )^^Eh=Kbj
fileFetch.start(); PAUepO_
} &LD=Zp%
catch(Exception e){e.printStackTrace ();} }bZcVc2
#F~^m
4*vV9*'!
} *;noZ9{"+
ee+*&CT)
<PayP3E
public static void main(String[] args) {@7{!I|eD
{ s,*kWy"jp
new TestMethod(); 6L)]nE0^
} jwe^(U
} tU :,s^E"#
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