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)); `V=F>s$W
} R:Tv'I1-L
for(int i=0;i<nEndPos.length-1;i++) R0bWI`$Z
{ ^9`~-w
nEndPos = nStartPos[i+1]; }-%:!*bLj
} i?IV"*Ob1N
nEndPos[nEndPos.length-1] = nFileLength; mL3 Q
} f1X]zk(=W
} U~_G *0
?Suv.!wfLl
%40+si3c
//启动子线程 (&xIBF_6
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; tN-B`d1
for(int i=0;i<nStartPos.length;i++) &U{"dJr
{ jGFDj"Y
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ?jHu,
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), *(j-jbA
nStartPos,nEndPos,i); "J*LR
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 7YQ689"J6B
fileSplitterFetch.start(); 8rM1kOCf
} @h)X3X
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), j\TS:F^z
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Xf*}V+&WN
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", *@[N~:z/
nEndPos = " + nFileLength); p0@l581
// fileSplitterFetch[nPos.length-1].start(); {^6<Ohe4j
_v +At;Y
a.B<W9$`
//等待子线程结束 {z*`* O@
//int count = 0; 8Lh[>|~=
//是否结束while循环 -< }#ImTN
boolean breakWhile = false; jU_#-<'r
L;'C5#GN
?v$1Fc55
while(!bStop) [A46WF>L
{ [K#pU:lTH
write_nPos(); @2R+?2 j
Utility.sleep(500); 4KZ)`KPE
breakWhile = true; GL'zNQP-
*Fz#x{zt
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for(int i=0;i<nStartPos.length;i++) (qg~l@rf
{ u%rB]a$/
if(!fileSplitterFetch.bDownOver) S<nbNSu6+
{ ah|`),o(k
breakWhile = false; X:d[eAu0
break; P(Z\y^S
} Ops""#Zi
} @W\H%VR
if(breakWhile) &T[BS;
break; $Y<(~E$FX
T(iL#2^
?PDrj/: *
//count++; &ZAc3@l[c
//if(count>4) "MU)8$d
// siteStop(); zR_yxs'
} O`FuXB(t
AW/)R"+
]]lM)
System.err.println("文件下载结束！"); SCKpW#2dP{
} hsHtLH+@
catch(Exception e){e.printStackTrace ();} NK|m7(
} *tL1t\jY
+<W8kb
{pM3f
//获得文件长度 o>oZh1/\T,
public long getFileSize() .aE%z/@s=
{ 2~q(?wY
int nFileLength = -1; R4Si{J*O
try{ O>sE~~g]?
URL url = new URL(siteInfoBean.getSSiteURL()); Ll'!aar,
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); _~_6qTv-d
httpConnection.setRequestProperty("User-Agent","NetFox"); WDQw)EUl&
HK!Vd_&9,
uc-Go 6W
int responseCode=httpConnection.getResponseCode(); n9r3CLb[
if(responseCode>=400) wVY;)1?
{ "U%jG`q
processErrorCode(responseCode); 7T@"2WYat
return -2; //-2 represent access is error ~AG."<}
} u@$pOLI
)0xEI
aIABx!83>
String sHeader; NZ?|#53
.47tj`L
4Q FX
for(int i=1;;i++) %QKRl5RM-
{ "f3KE=cUm
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ?ne!LDlE|
//Utility.log(in.readLine()); wO3K2I]>0
sHeader=httpConnection.getHeaderFieldKey(i); /e4#DH
if(sHeader!=null) &4-rDR,
{ 7z4u?>pne*
if(sHeader.equals("Content-Length")) 6N]V.;0_5
{ 1[r;
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); {qkd63X
break; o=N_0.
} ,Jh('r7
} b=j]tb,
else O.~@V(7ah
break; d*TpHLm
} SK_i 3?
} +i.b&PF'H
catch(IOException e){e.printStackTrace ();} >!|(n@
catch(Exception e){e.printStackTrace ();} Hxzdxwz%$
hg=BXe4:
1O]27"9
Utility.log(nFileLength); uSi/|
Je~d/,^WU
~ E|L4E
return nFileLength; yNu%D$6u7
} J>Uzd, /
i&dMX:fRd
%*wOJx
//保存下载信息（文件指针位置） x#s=eeP1
private void write_nPos() VIjsz42C
{ 58 Rmq/6s
try{ W9ewj:4\0
output = new DataOutputStream(new FileOutputStream(tmpFile)); sCF7K=a
output.writeInt(nStartPos.length); xr\wOQ*`
for(int i=0;i<nStartPos.length;i++) @YfCS8 eH
{ Cq,hzi-
// output.writeLong(nPos); >4}2~;
output.writeLong(fileSplitterFetch.nStartPos); WxFrqUz
output.writeLong(fileSplitterFetch.nEndPos); Fl^}tC
} Y8yRQzu
output.close(); !.ot&EbE
} 3e.v'ccK&
catch(IOException e){e.printStackTrace ();} bs_"Nn?
catch(Exception e){e.printStackTrace ();} dQ4K^u
} ^"d!(npw
^v].mV/
k$7@@?<
//读取保存的下载信息（文件指针位置） !B_?_ a
private void read_nPos() <NO?B+ ~]
{ #e:*]A'I
try{ &i~AXNw
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); De*Z UN|<
int nCount = input.readInt(); n|oAfJUk,
nStartPos = new long[nCount]; (gl/NH!
nEndPos = new long[nCount]; @BZ6{@*
for(int i=0;i<nStartPos.length;i++) Q`]El<$
{ kFG>Km(y}
nStartPos = input.readLong(); hp E?
nEndPos = input.readLong(); vZns,K#4H\
} uUczD 8y
input.close(); R.EA5X|_
} )A4WK+yD$z
catch(IOException e){e.printStackTrace ();} zaVDe9B,7
catch(Exception e){e.printStackTrace ();} |ei?s1)
} aQEMCWxZ
J0U9zI4
+{j? +4(B
private void processErrorCode(int nErrorCode) 43;@m}|7$
{ _r}oYs%1
System.err.println("Error Code : " + nErrorCode); @:~O
} f*g>~!
t?0D*!D
rwlV\BU
//停止文件下载 AVR9G^ce_
public void siteStop() Lw]:/x
{ ~nk'ZJ
bStop = true; nuB@Fkr
for(int i=0;i<nStartPos.length;i++) OT9\K_
fileSplitterFetch.splitterStop(); e_wz8]K)n
gq6C6
Oifu ?f<r
} $+<X 1
} 6?0^U 9
//负责部分文件的抓取 gnoV>ON0
**FileSplitterFetch.java |Mp_qg?g
*/ zJ#e3o.
package NetFox; WG;1[o&
A`7uw|uO$
MO:##C
import java.io.*; QY2!.a^q
import java.net.*; @\_tS H
ih?_ fW
| %af}# FQ
public class FileSplitterFetch extends Thread { w.cQ|_
I~qS6#%r
A>$VkGo
String sURL; //File URL ,LXuU8sB
long nStartPos; //File Snippet Start Position Xu$xO(
long nEndPos; //File Snippet End Position ^6+P&MxM
int nThreadID; //Thread's ID 2C%{A
boolean bDownOver = false; //Downing is over f{lg{gA(
boolean bStop = false; //Stop identical LS?hb)7
FileAccessI fileAccessI = null; //File Access interface `"M=ZVk
A==P?,RG
>#R<*?*D}
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ~\K+)(\SNp
{ "gdmRE{x
this.sURL = sURL; JW&/l
this.nStartPos = nStart; >.PLD} zE_
this.nEndPos = nEnd; Q/iaxY#
nThreadID = id; mqk~Pno|<
fileAccessI = new FileAccessI(sName,nStartPos);//定位 b^PYA_k-Xn
} uj&^W[s
A$W,#`E
7I`e5\ u
public void run() q+t*3;X.
{ fk P@e3
while(nStartPos < nEndPos && !bStop) `6!l!8 v
{ ReP7c3D>p
Qg?^%O'
E'$r#k:o
try{ #HB]qa
URL url = new URL(sURL); !5 %c`4
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); _p7c<$;
httpConnection.setRequestProperty("User-Agent","NetFox"); p[&'*"o!/
String sProperty = "bytes="+nStartPos+"-"; IQdiVj
httpConnection.setRequestProperty("RANGE",sProperty); D<}KTyG]
Utility.log(sProperty); oj@B'j
5_M9T3
CIQo2~G
InputStream input = httpConnection.getInputStream(); Hw<t>z k
//logResponseHead(httpConnection); br<,?
?YX2CJ6N
g!D?Yj4
byte[] b = new byte[1024]; Bfaj4i;_
int nRead; uI-te~]
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) "sf8~P9qy
{ rO 6oVz#x
nStartPos += fileAccessI.write(b,0,nRead); ;04doub
//if(nThreadID == 1) sxl29y^*
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); `#2}[D
} 2#ha Icm"
rayC1#f
?bQ~+M\
Utility.log("Thread " + nThreadID + " is over!"); Az6f I*yP
bDownOver = true; _7]* 5Pxo
//nPos = fileAccessI.write (b,0,nRead); I9ubVcV8
} 2@1A,
catch(Exception e){e.printStackTrace ();} sju. `f>-r
} {k}S!T
} <"AP&J'H
F^&_O*"
6\g]Y
//打印回应的头信息 zfO0+fMH
public void logResponseHead(HttpURLConnection con) znFa4
{ MaXgy|yB1
for(int i=1;;i++) r3/H_Z
{ xgL*O>l)
String header=con.getHeaderFieldKey(i); a~7`;Ar
if(header!=null) (5;w^E9*n;
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 1Xt%O86
Utility.log(header+" : "+con.getHeaderField(header)); [$]vi`c2
else d;9 X1`"
break; QOEcp% 6I}
} xg/3*rL
} ?W9$=
AlIFTNg:"
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public void splitterStop() lycY1lK
{ 6jiVz%`=Z
bStop = true; 8"LvkN/v^
} :u`
\$V~kgQ0
z(aei(U=
} y0M^oLx
b(I-0<
(m\PcF
/* eFp4MD8?
**FileAccess.java %w=*4!NWb
*//文件访问(定位，写) O]~cv^
package NetFox; VW I{ wC
import java.io.*; =\ iV=1iB
6^s=25>p
bf-.SX~
public class FileAccessI implements Serializable{ |(*ReQ?=
cMsm[D{b
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 cc*A/lD
RandomAccessFile oSavedFile; %/CCh;N#
long nPos; 't{~#0d=
1xar L))
e54wAypPOl
public FileAccessI() throws IOException BYyR-m
{ #O/ihRoaO
this("",0); s}uOht} o
} /d&zE|!
HO/Ij
|gA~E>IqF
public FileAccessI(String sName,long nPos) throws IOException c-z ,}`
{ 81O`#DfZ
oSavedFile = new RandomAccessFile(sName,"rw"); Z[RE|l{
this.nPos = nPos; =[FNZ:3
oSavedFile.seek(nPos); 200/
} kKr7c4q
y>3Zh5=
3u^U\xB
public synchronized int write(byte[] b,int nStart,int nLen) f6j;Y<}' g
{ >_jT.d
int n = -1; 1\=)b< y
try{ C,P>7
oSavedFile.write(b,nStart,nLen); Pb]: i+c)
n = nLen; %# ?)+8"l
} ?]]>WP
catch(IOException e) 6.ASLH3#
{ casva;
e.printStackTrace (); PB_+:S^8
} B<u6Z!Pp2
*8M0h9S$
<kN4@bd;
return n; y>_lxLhmO#
} szu!*wc9
f',n'
T@GT=1E)
} {Xb 6wQ"
p#wQW[6
(/Lo44wT
/* 6oMU) DIa
**SiteInfoBean.java SMY,bU'a
*/ oDogM`T`
package NetFox; {`2! 3= "
T!0o(Pp<
{?!=~vp
public class SiteInfoBean { _dky+ E
I`^ 7Bk.r
Ua\]]<hj"
private String sSiteURL; //Site's URL 47 xyS%X
private String sFilePath; //Saved File's Path umhg O.!
private String sFileName; //Saved File's Name @E %:ALJ
private int nSplitter; //Count of Splited Downloading File thy)J.<J
sG[v vm
T2<?4^xN
public SiteInfoBean() {VtmQU?cJ
{//nSplitter的缺省值为5 cVYDO*N2T
//default value of nSplitter is 5 B+[ri&6X\
this("","","",5); M!Q27wT8O
} F6 ?4&h?n
<E/4/ ANN
?f f!(U
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) NF8'O
{ }'L7<_
sSiteURL= sURL; 'APtY;x^{
sFilePath = sPath; bnHQvCO3$
sFileName = sName; :>4pH
this.nSplitter = nSpiltter; ]CHO5'%,$
1BK!<}yI{
:FB-GNd
} sQUJ]h
3D32'KO_"
NbgK#;
public String getSSiteURL() zGzeu)d
{ N^</:R
return sSiteURL; H3\4&q
} .'foS>W=t
tljZE)
<LL+\kfTZO
public void setSSiteURL(String value) /e5' YVP
{ cq:<,Ke
sSiteURL = value; zG-pqE6
} fy9mS
011 N
KYa}k0tVAp
public String getSFilePath() Q+@/.qJ
{ [A~n=m5H
return sFilePath; k{\wjaf)
} DwSB(O#X
DEJ0<pnQr
WV5z~[
public void setSFilePath(String value) #J=^CE
{ v~E\u
sFilePath = value; )S?.YCv?
} 6d~[j<@2
N{+6V`\
X 4L"M%i
public String getSFileName() K^32nQX
{ 5i71@?q;
return sFileName; PL"u^G`
} TwPpZ@
D)shWJRlvW
g Va;!
public void setSFileName(String value) (sM$=M<$
{ B|9[DNd
sFileName = value; W5i{W'
} p>M8:,
m\*;Fx
f2h`bO
public int getNSplitter() Ln-UN$2~F
{ T{WJf-pI
return nSplitter; ZkWX4?&OMt
} WAq)1gwN
!s^[|2D_U
&<nj~BL
public void setNSplitter(int nCount) -Cn x!g}
{ up_Qv#`Q
nSplitter = nCount; +"}#4
} r?9D/|`
} S<*h1}V3/
m8}c(GwcP
J|$UAOEDa
/* 8O^<#lh
**Utility.java g\.O5H9Od
*/ B1^9mV'O
package NetFox; r4MPs-}oF
>o/+z18x
B`<a~V
public class Utility { ,"en7
7a0T]
c"*xw8|
public Utility() LI}@qLe
{ *ggai?
\]Bwib%h
F)8M9%g5m
} shkyN
g9~QNA
//线程睡眠 >DM^/EAG{
public static void sleep(int nSecond) iQd,xr
{ ^7Z#g0{^w
try{ 2I[(UMI$7
Thread.sleep(nSecond); z:1"d R
} 7&`Yl[G
catch(Exception e) c`Q#4e]%_
{ z(!K8 T
e.printStackTrace (); O'rz
} ,gO(zI-1
} O[Yc-4
PAD&sTjE*
//日志 BbIg]E/G
public static void log(String sMsg) q2+`a;_S
{ f|+aa6hN
System.err.println(sMsg); E!EENg
} 1[] 9EJ
QnJd}(yN
#fVk;]u`[3
public static void log(int sMsg) Hb&C;lk
{ 0_&5S`tj
System.err.println(sMsg); n@=D,'cn
} XpH d"(*
} dBm!`;r4
vu@@!cT6e
[,yYr
/* @1vpkB~ w
**TestMethod.java )+ (GE
*/ gmUX 2x(
package NetFox; vqhu%ZyP
}PUY~ u
a7U`/*
public class TestMethod { bZ SaL^^(
ugV/#v O
o}b_`O
public TestMethod() WSxE/C|[
{ ///xx/weblogic60b2_win.exe +/>XOY|Ie
try{ P>nz8NRq
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 'T+v&M
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); (z.4er}o
SiteFileFetch fileFetch = new SiteFileFetch(bean); eWGaGRem
fileFetch.start(); 3D-VePM=`
} jn]:*i;i
catch(Exception e){e.printStackTrace ();} jPIOBEIG
GZ1c~uAu
&{e:6t
} PfN[)s4F{R
7pO/!Lm
>&[q`i{
public static void main(String[] args) O0_kLH$.
{ /l` "@
new TestMethod(); e_+SBN1`P&
} ' OXL'_Xl
} sl_f+h0
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