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)); *nS}1(u]
} i!0w? /g9
for(int i=0;i<nEndPos.length-1;i++) RN:VsopL
{ "/H B#
nEndPos = nStartPos[i+1]; _G3L+St
} h,-2+}
nEndPos[nEndPos.length-1] = nFileLength; 8xf]zM"Q
} YX*NjXL
} )(b,v/:
t&|M@Ouet
~-2%^ovB
//启动子线程 j IO2uTM~
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; zplAH!s5''
for(int i=0;i<nStartPos.length;i++) 6sceymq
{ 1. A@5*Q
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), efzS]1Jpz
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), hc7"0mVd{
nStartPos,nEndPos,i); X%(1C,C(
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); '`s\_Q)hG_
fileSplitterFetch.start(); ul(pp+%S
} 7`xeuK
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Z4ekBdmCL
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); (F=/r]Q
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", A-"2sp*t
nEndPos = " + nFileLength); ohEIr2
// fileSplitterFetch[nPos.length-1].start(); F:$*0!
Dh+<|6mx
z`]sWi F0
//等待子线程结束 QC\r|RXW
//int count = 0; #su R[K*S
//是否结束while循环 Z$*m=]2
boolean breakWhile = false; ,8.Fd|#L
813t=A
Rtywi}VV2
while(!bStop) r0^*|+
{ $Gs9"~z?;
write_nPos(); @kstG3@
Utility.sleep(500); r+%$0eB1^
breakWhile = true; C"SG':
pu-X -j
t[e`wj+qz
for(int i=0;i<nStartPos.length;i++) k2-+3zx
{ P~}Yj@2
if(!fileSplitterFetch.bDownOver) ZuLW%z.
{ ol3].0Vc]
breakWhile = false; =w!>/#U
break; 9 AWFjoXl"
} zrDcO~w
} =Ju%3ptH0
if(breakWhile) 5,_DM
break; JnE\z*NB
y.>1r7
Z\[6'R4.#
//count++; E\5Cf2Ox
//if(count>4) )#os!Ns_A
// siteStop(); tl6x@%\
} x@*RF:\}
;9MIapfUd(
tD^$}u6
System.err.println("文件下载结束！"); ,DL%oQR
} Cl>|*h+m
catch(Exception e){e.printStackTrace ();} zp'Vn7
} Cfr2~w
F:~k4uTW\b
b?U2g?lN:
//获得文件长度 [iXkv\
public long getFileSize() <`)vp0
{ 2#81oz&K
int nFileLength = -1; ~J:qG9|]}
try{ zhZ!!b^6<
URL url = new URL(siteInfoBean.getSSiteURL()); A)9F_;BY
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); `g+Kv&546
httpConnection.setRequestProperty("User-Agent","NetFox"); rtxG-a56Q
\yhj{QS.k
1xTNrLW
int responseCode=httpConnection.getResponseCode(); FZBdQhYF
if(responseCode>=400) % `\}#
{ pqF!1
processErrorCode(responseCode); P=<>H9p:o
return -2; //-2 represent access is error c BcZ@e;
} STjk<DP(
yedEI[_4
Mp`!zwR
String sHeader; [QDM_n
a{ p1Yy-]
X..<U}e
for(int i=1;;i++) 2{|mL`$04<
{ C2;Hugm4
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); Y3.^a5o
//Utility.log(in.readLine()); Uz_OUTFM
sHeader=httpConnection.getHeaderFieldKey(i); G,X>f?
if(sHeader!=null) &gdhq~4#
{ 7Z< 2`&c7
if(sHeader.equals("Content-Length")) 2n3!pZ8
{ s}lp^Uh=
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); +.J/7gD
break; `f<&=_,xfH
} 3f-J%!aH
} myOdf'=
else ;q33t%j
break; Sa9p#OQ
} FY9nVnIoI
} v*JXrB&x
catch(IOException e){e.printStackTrace ();} bH}?DMq]O
catch(Exception e){e.printStackTrace ();} w6
dZkj|Ua~
P`L, eYc
Utility.log(nFileLength); ePo :::
*&BS[0;
)|,Zp`2/
return nFileLength; T@R2H&L
} -Oplk*
sTmdoqTK!
` InBhU>
//保存下载信息（文件指针位置） p~yGp]yJ9
private void write_nPos() YBupC!R
{ #BW:*$>}
try{ Utj4f-M
output = new DataOutputStream(new FileOutputStream(tmpFile)); O`f[9^fN
output.writeInt(nStartPos.length); 5 \iX%w@
for(int i=0;i<nStartPos.length;i++) T9?8@p\}(
{ !BDJU
// output.writeLong(nPos); R*O<(
output.writeLong(fileSplitterFetch.nStartPos); PUEEfq!%
output.writeLong(fileSplitterFetch.nEndPos); 4Z0Y8y8)
} wCt!.<, .
output.close(); b *Ca*!
} |xFSGrC
catch(IOException e){e.printStackTrace ();} }qg.Go
catch(Exception e){e.printStackTrace ();} m](q,65 2
} JN-W`2
-ZH6*7!
HX#$ ^@Q(
//读取保存的下载信息（文件指针位置） ,CIsZ1[VS
private void read_nPos() KkZS6rD\
{ dmYgv^t
try{ Z#zXary5s
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 5}4>vEn
int nCount = input.readInt(); 85rjM#~
nStartPos = new long[nCount]; vAqVs5 j
nEndPos = new long[nCount]; \ZtF,`Z
for(int i=0;i<nStartPos.length;i++) {JtfEna
{ /Jc54d
nStartPos = input.readLong(); )@_5}8
nEndPos = input.readLong(); vw*,_f
} -r%k)4_
input.close(); h3Y|0-D
} {ewo-dva
catch(IOException e){e.printStackTrace ();} \t ^9UN
catch(Exception e){e.printStackTrace ();} jJ3dZ<#
} t_hr${
^Is#_Z|
15_Px9
private void processErrorCode(int nErrorCode) +:&|]$8<
{ 'wjL7PI
System.err.println("Error Code : " + nErrorCode); r:5u(2
} q|QkJr<
J3y4D}
<_#a%+5d
//停止文件下载 }CQ)W1mO"
public void siteStop() .$zo_~ mR
{ &+")~2 +
bStop = true; H'?dsc
for(int i=0;i<nStartPos.length;i++) !Q=xIS
fileSplitterFetch.splitterStop(); ^oDSU7j5,
UF;iw
zXGi
} k3UKGP1
} zhVkn]z~*
//负责部分文件的抓取 Qsg([K
**FileSplitterFetch.java vt(cC))
*/ EttQ<z_T
package NetFox; eT@,QA(3
k? !'OHmBL
s!?T$@a=
import java.io.*; lr9s`>9
import java.net.*; >#|%y>g .o
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cm`x;[e6l
public class FileSplitterFetch extends Thread { F!cRx%R
Z`x*Igf8
:|N(:W>=$Y
String sURL; //File URL W$`p ,$.n
long nStartPos; //File Snippet Start Position HG&rE3@
long nEndPos; //File Snippet End Position ]L_h3Xz\X
int nThreadID; //Thread's ID oT*qMLdn
boolean bDownOver = false; //Downing is over :y^%I xs{1
boolean bStop = false; //Stop identical c}mWAZ=wF
FileAccessI fileAccessI = null; //File Access interface -GT&46hX
sW0<f&3
'\R/-.
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException i|CAN,'
{ WoWmmZ
this.sURL = sURL; _e$T'*q
this.nStartPos = nStart; q]wP^;\Jl
this.nEndPos = nEnd; GI)eq:K_U8
nThreadID = id; S\ ) ~9?
fileAccessI = new FileAccessI(sName,nStartPos);//定位 "U*6?]f
} lH"4"r
V]P%@<C
VP_S[+Zv~
public void run() Qw.j
{ f~{4hVA
while(nStartPos < nEndPos && !bStop) E\vW>g*W
{ />dYkIv
xnPi'?A]
W6jdS;3
try{ ehyCAp0oI
URL url = new URL(sURL); {qb2!}FQ
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Kq;s${ |G
httpConnection.setRequestProperty("User-Agent","NetFox"); x"{WLZ
String sProperty = "bytes="+nStartPos+"-"; O_^t u?x
httpConnection.setRequestProperty("RANGE",sProperty); Itv}TK eF
Utility.log(sProperty); vu`,:/|h
%)sG 34
s'=w/os
InputStream input = httpConnection.getInputStream(); r;8X6C
//logResponseHead(httpConnection); q1,jDJglZ
XG01g3
%OAvhutS
byte[] b = new byte[1024]; >%c7|\q[R
int nRead; >M^4p
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) .{4U]a;[
{ xH>2$ ;f
nStartPos += fileAccessI.write(b,0,nRead); #?fKi$fS;L
//if(nThreadID == 1) l@`Do[
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); i]}`e>fF
} ]OLe&VRix
YOQ>A*@4
s> JWNP
Utility.log("Thread " + nThreadID + " is over!"); Q=#N4[W'
bDownOver = true; ;lc/FV[/
//nPos = fileAccessI.write (b,0,nRead); Fm4)|5
} UpS7>c7s
catch(Exception e){e.printStackTrace ();} ^(~%'f
} M&^Iun
} 1XJLGMW,
Wph@LRB]
mH/9J
//打印回应的头信息 2dnyIgi
public void logResponseHead(HttpURLConnection con) 'yNS(Bg=
{ Zx 5Ue#I
for(int i=1;;i++) t>JPK_b0
{ `w EAU7m:
String header=con.getHeaderFieldKey(i); Z Z9D6+R
if(header!=null) Uq^-km#a
//responseHeaders.put(header,httpConnection.getHeaderField(header)); L'r gCOJ<
Utility.log(header+" : "+con.getHeaderField(header)); UB,:won
else a}[ 1*_G
break; $M|
} /<Yz;\:Jy
} NM4b]>
+AYB0`X)
bz|-x"qk
public void splitterStop() nj6|WJ
{ .^V9XN{'a
bStop = true; l#fwNM/F
} tFu"h1
CJe~>4BT
4^_'LiX3[
} 9qI#vHA
P~M<OUg
T':} p2}w+
/* PIM4c
**FileAccess.java % 9} ?*U
*//文件访问(定位，写) 3NSX(gC%
package NetFox; Z~v-@
import java.io.*; jW;g{5X
<3!Q Xc
4~~G i`XE
public class FileAccessI implements Serializable{ T_Cj=>L
+{L=cWA"
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 S,vh
RandomAccessFile oSavedFile; a~&euT2
long nPos; lw=!v%L
q#\4/Dt
>!WH%J
public FileAccessI() throws IOException uUJH^pW
{ /Suh&qw>
this("",0); 8 t`lRWJ
} ff5 e]^,
$3]]<oH
SGP)A(,k9
public FileAccessI(String sName,long nPos) throws IOException 8:fq!m
{ Q/`W[Et
oSavedFile = new RandomAccessFile(sName,"rw"); V,&A? Y
this.nPos = nPos; qh#?a'
oSavedFile.seek(nPos); RX?y}BDo0
} G_S2Q @|Q
PnZY%+[I
#AF.1;(k
public synchronized int write(byte[] b,int nStart,int nLen) `oOVR6{K9
{ s y>}2orj~
int n = -1; `Ha<t.v(
try{ ::sk)
oSavedFile.write(b,nStart,nLen); 0SV4p.
n = nLen; "Pa y2
} b=XXp`h~a
catch(IOException e) qaG8:
{ dy3fZ(=q^
e.printStackTrace (); =[LUOOR*]
} 8 `}I]
Ru@ { b`
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return n; n!&F%|o^^
} *K;s*-|U
Igh=Z %
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} rw.DKM'
rIeOli:<
+%R{j|8#
/* t6Nkv;)>@
**SiteInfoBean.java (?1/\r
*/ i-,_:z=J
package NetFox; D[dI_|59a
B7(bNr
=@!s[
public class SiteInfoBean { H1r8n$h
+}iuTqu5
b<j*;n.
private String sSiteURL; //Site's URL !md1~g$rN
private String sFilePath; //Saved File's Path 6#kmV
private String sFileName; //Saved File's Name "'~&D/7
private int nSplitter; //Count of Splited Downloading File 5DL(#9F8b9
.*&F
P c'\
public SiteInfoBean() La$?/\Dv)
{//nSplitter的缺省值为5 BMb0Pu8
//default value of nSplitter is 5 g}$B4_sY
this("","","",5); *g"Xhk
} e\.
r*UE>_3J
`t>:i!s/
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) RG:_:%@%}
{ #6@4c5{2=4
sSiteURL= sURL; g`dAj4B
sFilePath = sPath; W1ql[DqE{
sFileName = sName; <OTx79m
this.nSplitter = nSpiltter; O?0`QMY
q +!i6!6r
c~u91h?
} !M}ZK(
YL/B7^fd8
")9jt^
public String getSSiteURL() H3+P;2{
{ 465?,EpS
return sSiteURL; vF9fXY=
} (w`j?c1
[I,s:mn
DDe`Lb%%
public void setSSiteURL(String value) _8e0vi!~2
{ GYtp%<<9;
sSiteURL = value; |eK^Yhym
} wQYW5X
f1|&umJ$
=g$%jM>35
public String getSFilePath() cToT_Mk
{ ^bECX<,H
return sFilePath; '#>(JN5\
} uQg&]bSv
"Ug+#;}p$
7MIrrhk
public void setSFilePath(String value) J7wIA3.O
{ o,'Fz?[T%
sFilePath = value; CP Ju=
} Va^(cnwa
B#4'3Y-3
Y+Cv9U0
public String getSFileName() e6Kyu*
{ VBz G`&NG
return sFileName; Z GrDa
} 6S^JmYq
:XB^IyO-A
aX? tnDv
public void setSFileName(String value) f1 `E-
{ JG@Zb}b
sFileName = value; xn anca
} ?N&s.
6Oy6r
ohi0_mBz
public int getNSplitter() #!t6'*
{ {/i&o
return nSplitter; *RFBLCt
} t(UdV
04:QEC"9mj
uG(XbDZZ1W
public void setNSplitter(int nCount) DK1{Z;Z
{ %rO)w?
nSplitter = nCount; 0~e6\7={
} (?ZS9&y}
} Tj6kCB
p5J!j I=
95Q^7oI
/* ~R~eQ=8
**Utility.java ]3uj~la
*/ g#o9[su
package NetFox; X?Or.
.\8LL,zT
=z\/xzAwX
public class Utility { B^C5?
mt4X
czH# ~
public Utility() ~'N+O K
{ zZP&`#TAy
.>p.k*vU
R#!Urhh
} qUk-BG8^
}O2P>Z?V
//线程睡眠 p ^Y2A
public static void sleep(int nSecond) b1yS1i D
{ PsBLAr\ah
try{ 0@RVM|
Thread.sleep(nSecond); =b>e4I@
} ynJ)6n7a
catch(Exception e) 9[h8Dy
{ ,fvhP $n
e.printStackTrace (); s1p<F,
} n>xuef
} iB+ _+A
@>+`1C
//日志 4)Ew rU
public static void log(String sMsg) qoEZ>
{ .x1.`Y
System.err.println(sMsg); tg7QX/KX
} 9Dd`x7$a
g|M>C:ZT
q siV
public static void log(int sMsg) z&z5EtFUTh
{ 6O"y
System.err.println(sMsg); : :928y
} (&M,rW~Qxs
} GN+!o($
/!U(/
A-u!{F
/* g\H~Y@'{
**TestMethod.java 2Hk21y\
*/ $F6GCM3Cx
package NetFox; G`f|#-}
|}@teN^J*U
bVr`a*EM
public class TestMethod { lU.aDmy<
|(uo@-U
sn+ kFvk}S
public TestMethod() o;>qsn8
{ ///xx/weblogic60b2_win.exe +ZkJ{r0,(
try{ IiV]lxiE]
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); " s/ws
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); f7Gs1{
SiteFileFetch fileFetch = new SiteFileFetch(bean); F(w<YU%6
fileFetch.start(); f'Rq#b@
} CIz_v.&:
catch(Exception e){e.printStackTrace ();} &UAYYH
Rp>%umDyL
j{@li1W@
} ~xcU6@/
CHDt^(oa!B
xu>grj
public static void main(String[] args) rr2^sQ;_
{ [@NW
new TestMethod(); Fe2t[y:8h
} ;8cTy8
} 0CI\Yd=
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