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)); Lu.D,oP
} q^:>sfd
for(int i=0;i<nEndPos.length-1;i++) ~r<@`[-L
{ x-wIgo+
nEndPos = nStartPos[i+1]; pGQP9r%
} MAhJ>qe8 p
nEndPos[nEndPos.length-1] = nFileLength; k[TVu5R
} mAycfa
} j]-0m4QF
3j'A.S
,EkzBVgo
//启动子线程 W[pOLc-
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; I r8,=
for(int i=0;i<nStartPos.length;i++) .hBq1p
{ Y7WxV>E
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), b2}>{Li0
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), W62 $ HI
nStartPos,nEndPos,i); ~%SmH[i
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); RCXm</
fileSplitterFetch.start(); L-B"P&
} HGuU6@~hu
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), &|/@;EA$8
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 4o+SSS
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 1J`<'{*
nEndPos = " + nFileLength); #6t 4 vJ1
// fileSplitterFetch[nPos.length-1].start(); "r!>p\.0O
#w%d
)7$1Da|.
//等待子线程结束 p`/"e<TP
//int count = 0; J1i{n7f=@
//是否结束while循环 t)#8r,9c
boolean breakWhile = false; Gv ';
xC3h m
w %4SNR
while(!bStop) p>4tPI}bf
{ gYeKeW3)
write_nPos(); *QKxrg
Utility.sleep(500); ]!7%)
breakWhile = true; ?]*WVjskE
st- z>}
0c2O'&$au
for(int i=0;i<nStartPos.length;i++) U0%T<6*H
{ [/h3HyZ.
if(!fileSplitterFetch.bDownOver) 9v\x&h
{ vY 0EffZ
breakWhile = false; 0P{^aSxTP
break; -L4fp
} Nk.m$
} $|kq{@<
if(breakWhile) vbt0G-%Z
break; <x QvS^|[
zKh^BwhO|X
i-.]onR
//count++; qPI\Y3ZU
//if(count>4) s9[?{}gd
// siteStop(); R07]{
} cTC -cgp
sj9j47y
:B^YK].
System.err.println("文件下载结束！"); *~h@KQm7
} {gL8s
catch(Exception e){e.printStackTrace ();} M =/+q
} +3>)r{#k
OC?a[^hB^)
?;GbK2\bj
//获得文件长度 YC!IIE_
public long getFileSize() .<m${yU{3
{ fL^$G;_?3
int nFileLength = -1; !.2tv
try{ =3h?!$#?
URL url = new URL(siteInfoBean.getSSiteURL()); DOaTp f
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); C VXz>oM
httpConnection.setRequestProperty("User-Agent","NetFox"); d4ga6N3'
9"W3t]
Yvi.l6JL
int responseCode=httpConnection.getResponseCode(); DpRGPs
if(responseCode>=400) 5T*Uq>x0
{ OLH[F
processErrorCode(responseCode); 3_DwqZ 'O
return -2; //-2 represent access is error 8O[br@h:5
} ;JuBybJb
#QUQC2P(~
#&k`-@b5|
String sHeader; e/7rr~"|
;\'d9C
7@W}>gnf
for(int i=1;;i++) w@![rH6~F
{ `4SwdW n
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); D'8xP %P
//Utility.log(in.readLine()); MyZ5~jnr\
sHeader=httpConnection.getHeaderFieldKey(i); <r>1W~bp.q
if(sHeader!=null) \CU-a`n
{ rSgOQ
if(sHeader.equals("Content-Length")) N*1{yl76x
{ T1-.+&<
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); \ u*R6z
break; [ML|,kq!
} kTW[)
} 3>T2k }
else A"3"f8P8a
break; gmqL,H#
} [PIh^DhK
} 5cF7w
catch(IOException e){e.printStackTrace ();} ~D0e\Q(A
catch(Exception e){e.printStackTrace ();} 5!s7`w]8*0
Al MMN"j
rq#\x{l
Utility.log(nFileLength); qo*%S
;hV-*;>
,I2x&Ys&.
return nFileLength; "d; T1
} 9Ai3p
CcJ%;.V,T
I3.cy i
//保存下载信息（文件指针位置） Op_(10|
private void write_nPos() >2s31 {
{ ]as+gZ8
try{ 4=nh' U38
output = new DataOutputStream(new FileOutputStream(tmpFile)); >ufLRGL>
output.writeInt(nStartPos.length); V[;^{,;
for(int i=0;i<nStartPos.length;i++) ?mp}_x#=
{ :|HCUZ*H(T
// output.writeLong(nPos); ==Ah& ){4^
output.writeLong(fileSplitterFetch.nStartPos); t"$#KP<
output.writeLong(fileSplitterFetch.nEndPos); jmBsPSGIC
} ,$+ P
output.close(); @hF$qevX
} 6n?0MMtR
catch(IOException e){e.printStackTrace ();} ]<BT+6L
catch(Exception e){e.printStackTrace ();} 8x`EUJ
} Ods~tM
Aa`R40yl
M:*)l(
//读取保存的下载信息（文件指针位置） u.@B-Pf[Eo
private void read_nPos() x+bC\,q
{ gSk0#Jt
try{ zq'KX/o
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); h:=W`(n5u
int nCount = input.readInt(); O~OM.:al&
nStartPos = new long[nCount]; AsfmH-4)
nEndPos = new long[nCount]; ._[uSBR'
for(int i=0;i<nStartPos.length;i++) Zs|m_O G
{ (:>Sh0.
nStartPos = input.readLong(); B%I<6E[D
nEndPos = input.readLong(); z7s}-w,
} veAdk9
input.close(); Eh+m|A
} S[e> 8
catch(IOException e){e.printStackTrace ();} zi_0*znw
catch(Exception e){e.printStackTrace ();} P r2WF~NuO
} Ou]!@s
Q"s]<MtdS
`sLD>@m
private void processErrorCode(int nErrorCode) $}t;c62
{ XD%GNZ
System.err.println("Error Code : " + nErrorCode); BC)1FxsGf
} bMB@${i}
^@ Xzh:
]1s6=
//停止文件下载 Xd@ d$
public void siteStop() v[4-?7-
{ G.~Ffk
bStop = true; ?/fC"MJq?
for(int i=0;i<nStartPos.length;i++) ,R}9n@JI^Y
fileSplitterFetch.splitterStop(); ncpNesB
wz{&0-md*'
S@@#L
} UE-1p
} 2f5YkmGc";
//负责部分文件的抓取 f&I5bPS7}
**FileSplitterFetch.java }BWT21'-Y
*/ F):1@.S
package NetFox; 629ogJo8
&3|l4R\
(z:qj/|
import java.io.*; wln"g,ct
import java.net.*; 1b<[/g9
t+#vcg,G
b/d1(B@
public class FileSplitterFetch extends Thread { )C$pjjo/`
l^2m7 7)
w7~cY=
String sURL; //File URL "I QM4:
long nStartPos; //File Snippet Start Position x~E\zw
long nEndPos; //File Snippet End Position E/2_@&U:}
int nThreadID; //Thread's ID bAEwjZ
boolean bDownOver = false; //Downing is over [JEf P/n|.
boolean bStop = false; //Stop identical AEd9H +I
FileAccessI fileAccessI = null; //File Access interface 9z+ZFIf7d
nP0rg
+t8#rT ^B
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException A3.*d:A
{ |`pDOd
this.sURL = sURL; O jH"qi
this.nStartPos = nStart; s;#,c(
this.nEndPos = nEnd; UHS"{%
nThreadID = id; L=gG23U&
fileAccessI = new FileAccessI(sName,nStartPos);//定位 )T@?.J`
} qb$M.-\ne
Q>I7.c-M|
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public void run() fW$1f5g"
{ p@eW*tE
while(nStartPos < nEndPos && !bStop) C,B{7s0-
{ mM'uRhO+
mZ g'
C6qGCzlG`
try{ A+KpECP
URL url = new URL(sURL); -ZoAbp$
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); =vsvx{o?
httpConnection.setRequestProperty("User-Agent","NetFox"); a>&dAo}
String sProperty = "bytes="+nStartPos+"-"; Zd]ua_)I%[
httpConnection.setRequestProperty("RANGE",sProperty); M63t4; 0A
Utility.log(sProperty); )O8w'4P5
NbK67p:
I:M15
InputStream input = httpConnection.getInputStream(); ^sF(IV[>
//logResponseHead(httpConnection); p: u@? k
l4YTR4D
}"STc&1
byte[] b = new byte[1024]; Qx8O&C?Ti
int nRead; H-3*},9
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) /}k?Tg/
{ bZ}T;!U?I
nStartPos += fileAccessI.write(b,0,nRead); w3M F62:
//if(nThreadID == 1) ~&D5RfK5f
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); +&.39q!
} 2LS91
x,c\q$8yH
v)~!HCG
Utility.log("Thread " + nThreadID + " is over!"); 2BO"mc<#$
bDownOver = true; 7 b{y
//nPos = fileAccessI.write (b,0,nRead); XdE|7=+s
} \CBL[X5tr
catch(Exception e){e.printStackTrace ();} S<g~VK!Tt
} t\O#5mo
} SmV}Wf
*t`=1Ioj
k/i&e~! \
//打印回应的头信息 xu@+b~C\
public void logResponseHead(HttpURLConnection con) vBV_aB1{
{ Ah;`0Hz;
for(int i=1;;i++) @DKph!cr
{ x??H%'rP
String header=con.getHeaderFieldKey(i); (Ft#6oK"
if(header!=null) SqVh\Nn
//responseHeaders.put(header,httpConnection.getHeaderField(header)); '/3\bvZ
Utility.log(header+" : "+con.getHeaderField(header)); _pkmHj(
else A27!I+M
break; ^xq)Q?[{
} ]'<"qY
} ,uZz?7mO
d~y]7h|
26MoYO!k
public void splitterStop() #<vzQ\~Y
{ db.~^][k
bStop = true; I.p"8I;
} wq]vcY9^
~JB4s%&
/}(\P@Z
} ;".]W;I*O
WL;2&S/{@
a[J_H$6H!
/* `82^!7!
**FileAccess.java "YN6o_*]
*//文件访问(定位，写) dK]#..
package NetFox; o[g]Va*8
import java.io.*; ue -a/a
,#hNHFa'JH
|5*:ThC[
public class FileAccessI implements Serializable{ <W/YC2b
#(-?i\i
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 oTveY
RandomAccessFile oSavedFile; ;oOv~YB7H
long nPos; EV_u8?va
/a\]Dwj5
+<)H2
public FileAccessI() throws IOException Is!+`[ma
{ 7TA&u'
this("",0); ckbD/+
} CIQ9dx7>
Fu65VLKh
hmI> 7@&
public FileAccessI(String sName,long nPos) throws IOException %V92q0XW
{ x) R4_3
oSavedFile = new RandomAccessFile(sName,"rw"); )jMk~;'r
this.nPos = nPos; Zig3WiD&
oSavedFile.seek(nPos); 9L>ep&u)^
} [pz1f!Wn
v"dl6%D"
B \.05<
public synchronized int write(byte[] b,int nStart,int nLen) US&:UzI.
{ B~%SB/eu
int n = -1; 9w-;d=(Q
try{ ! ~+mf^D
oSavedFile.write(b,nStart,nLen); O>IG7Ujl
n = nLen; ,PX7}//X^
} uC?/p1
catch(IOException e) j^ttTq|l
{ "MDy0Tj8EN
e.printStackTrace (); ~'LoIv20j)
} l>pnY%(A
MaP-
4TcW%
return n; tw<}7l_>Au
} Q.SqOHeJ
JiGS[tR
;eMb$px
} WDh*8!)
DK<}q1xi
rR(\fX!dg
/* ! ;R}=
**SiteInfoBean.java -IL' (vx
*/ {%z5^o1)
package NetFox; 7/bF04~%
la{o<||Aq
lht :%Ts$
public class SiteInfoBean { Gk)6ljL
g?>
C{YTHNn
private String sSiteURL; //Site's URL :(i=> ~O
private String sFilePath; //Saved File's Path XZxzw*Y1J
private String sFileName; //Saved File's Name Wbi12{C
private int nSplitter; //Count of Splited Downloading File 7qg. :h
<#lNi.?.
6^TWY[z2%
public SiteInfoBean() dbfI!4
{//nSplitter的缺省值为5 Cp#}x1{
//default value of nSplitter is 5 v#9Uy}NJ9
this("","","",5); 'L2[^iF9
} Jy0(g T
|qb-iXW=
&IFXU2t}
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) <^adt *m
{ f4^\iZ{`G
sSiteURL= sURL; {QT:1U\.
sFilePath = sPath; s+a#x(7{
sFileName = sName; tS[@?qP
this.nSplitter = nSpiltter; 1pTQMf a
J!iKW
bRx}ih
} }SGb`l
n;r W
HG)h,&nc-
public String getSSiteURL() 8b $e)
{ 1Pd2%
return sSiteURL; l6T5]$
} ?8$h%Ov-
.7n`]S/
P,7beHjf
public void setSSiteURL(String value) $WbfRyXi7'
{ %Pk@`t(3
sSiteURL = value; }M${ _D
} NJ(H$tB@
YF13&E2`\
<X]dR 6FT
public String getSFilePath() gm}zF%B"
{ 6"V86b0)h}
return sFilePath; z_87;y;=
} 'e7;^s
8LlWXeD9
{Lvta4}7(
public void setSFilePath(String value) D__*?frWpW
{ {y|j**NZ
sFilePath = value; n)rSgzI
} G\ /L.T
trL8oZ6
8-q4'@(
public String getSFileName() k;vhQ=
{ "=*
return sFileName; <nF1f(ky
} iuEQ?fp
t/a
?^ `EI}g
public void setSFileName(String value) |3 v+&eVi
{ 4|KtsAVp{
sFileName = value; >('Z9<|r:
} eed!SmP
$~:|Vj5iZ\
`MXGEJF
public int getNSplitter() <_-8)abK
{ IHj9n>c)[
return nSplitter; r~T3Ieb
} 41\V;yib
1lf]}V
rTM0[2N
public void setNSplitter(int nCount) o`\@Yq$.
{ m/NXifi8l
nSplitter = nCount; {iVmae
} xu*dPG)v
} "$|ne[b2
1'9YY")#
4z!(!J)
/* q@Sj$
**Utility.java yx/.4DW1Ua
*/ 2R`}}4<Z
package NetFox; s%t =*+L\
9E]7Etfw
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public class Utility { O:W4W=K
d# q8-
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public Utility() ri1:q.:I]
{ TS;?>J-
[^A>hs*
3Uni{Z]Q)
} fnudu0k
|%5nV=&\
//线程睡眠 %1e{"_$O9
public static void sleep(int nSecond) hOIk6}r4X
{ )n17}Qm`V
try{ 7|q _JdKoU
Thread.sleep(nSecond); O@? *5
} #nJ&`woZt
catch(Exception e) Ixv/xI
{ -gb'DN1BG
e.printStackTrace (); T>pz?e^5&
} !<j)D_
} bGa"r
pn4~?Aua0/
//日志 /&G )IY]g
public static void log(String sMsg) Fx'E"d
{ g+M& _n
System.err.println(sMsg); ,SSq4
} R%^AW2
K!_''Fg
"\1QJ
public static void log(int sMsg) W1p5F\ wt
{ -O?&+xIK&
System.err.println(sMsg); J1{ucFa
} >X-*Hu'U#
} ^l9NF
'.d]n(/lZd
%&b70]S(
/* QLe<).S1B2
**TestMethod.java :]^FTnO
*/ (TFo]c
package NetFox; ex-W{k$
gPg2Ve0Qy
nW`EBs
public class TestMethod { TGu]6NzyZ
<Z8^.t)|
]*JH~.p
public TestMethod() 6`;+|H<$
{ ///xx/weblogic60b2_win.exe gVI2{\a
try{ :_"%o=
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); :pPn)j$
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ~TfQuIvQB
SiteFileFetch fileFetch = new SiteFileFetch(bean); X3,+aL`
fileFetch.start(); Ld3!2g2y7&
} "4e{Cq
catch(Exception e){e.printStackTrace ();} OFcqouGE
rLOdQN
5RhP^:i@C
} +2S#3m?1
)90K^$93"
R SqO$~
public static void main(String[] args) 'or8CGr^p
{ !`EhVV8u-_
new TestMethod(); )NCkq~M
} 'ai!6[|SD
} DX%D8atrr
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