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)); z}z 6Vg
} T0TgV
for(int i=0;i<nEndPos.length-1;i++) ($or@lfs
{ Vl\8*!OL%
nEndPos = nStartPos[i+1]; ,*MAteD
} (<KFA,
nEndPos[nEndPos.length-1] = nFileLength; 3Z%~WE;I
} W{W8\
} 1LZ[i89&%
~;S
DV{0|E
//启动子线程 }huFv*<@'
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; {'@`:p&3r
for(int i=0;i<nStartPos.length;i++) a2%xW_e
{ M)6iYA%$
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), B9(@.
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), D`NPU
nStartPos,nEndPos,i); A29R5
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); dtx3;d<NsJ
fileSplitterFetch.start(); L'L[Vpx
} euiP<[|h=
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), -~] q?k?
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); A~)#
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", AC&)FY
nEndPos = " + nFileLength); mxEniy
// fileSplitterFetch[nPos.length-1].start(); M~eXC
aM7=>
)eD9H*mq
//等待子线程结束 (J 1:J
//int count = 0; GTuxMg`
//是否结束while循环 nr]:Y3KyxX
boolean breakWhile = false; sOqT*gwr:
hZ`<ID
{|{;:_.>
while(!bStop) 'zhv#&O
{ l9t|@9
write_nPos(); Rl{e<>O\^
Utility.sleep(500); nghpWODq
breakWhile = true; xQ,My
5RsO^2V:
N@#,YnPI
for(int i=0;i<nStartPos.length;i++) Lm3~< vP1e
{ oH='\M%+
if(!fileSplitterFetch.bDownOver) :Xi&H.k)p
{ g^: &Dh
breakWhile = false; u*=8s5Q[
break; 572{DC&T
} [nASMKK0
} mgE r+
if(breakWhile) ).3riR
break; J!\oH%FJp
pf$gvL
4G2iT+X-
//count++; "IN[(
//if(count>4) Qg]+&8!*
// siteStop(); +3F%soum95
} =1Hn<Xay0
p?2^JJpUb
R8-=N+hX
System.err.println("文件下载结束！"); ?[<#>,W
} yu>)[|-
catch(Exception e){e.printStackTrace ();} oJ?,X^~_
} < Dt/JA(p
BUS4 T#D
VVJIJ9L&C
//获得文件长度 9? y&/D5O
public long getFileSize() H<9_BA?
{ H~ E<ek'~
int nFileLength = -1; *7o@HBbF
try{ wZfY~
URL url = new URL(siteInfoBean.getSSiteURL()); q ;"/i*+3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 7epil
httpConnection.setRequestProperty("User-Agent","NetFox"); MfZamu5+F
bae;2| w
Y'<wE2ZL)
int responseCode=httpConnection.getResponseCode(); 3Fw7q"
if(responseCode>=400) :cvT/xhO
{ G=/^]E
processErrorCode(responseCode); #y-R*4G
return -2; //-2 represent access is error Du #>y!
} Cto>~pV
c] -
7M)<Sv
String sHeader; E#R1
o3$dl`'
I0*N "07n
for(int i=1;;i++) X-*LA*xbN
{ fjCFJ_
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); d$^@$E2f
//Utility.log(in.readLine()); y* :C~
sHeader=httpConnection.getHeaderFieldKey(i); U@9v(TfV
if(sHeader!=null) &F:%y(;{Y
{ WjguM
if(sHeader.equals("Content-Length")) :T{VCw:*
{ gBr/Y}I
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); S!rVq,| d
break; ,BFw-A
} xX|f{)<
} =QK ucLo
else 2H1 [oD[
break; _(-i46x}
} R"j<C13;%
} CG;+Z-"X
catch(IOException e){e.printStackTrace ();} g:Q:cSg<
catch(Exception e){e.printStackTrace ();} {n&GZG"f
0V?7'Em
U1`pY:P
Utility.log(nFileLength); MOPHu O{^
~)F_FS
osc A\r
return nFileLength; fZoQQ[s
} :k-@w5(
g/(BV7V
*eGG6$I
//保存下载信息（文件指针位置） -<L5;
private void write_nPos() G5%k.IRz
{ _0BQnzC=
try{ jn`5{ ]D
output = new DataOutputStream(new FileOutputStream(tmpFile)); #"8'y
output.writeInt(nStartPos.length); \H&;.??W
for(int i=0;i<nStartPos.length;i++) fR?'HsQg
{ %}JSR y
// output.writeLong(nPos); O0;mXH
output.writeLong(fileSplitterFetch.nStartPos); +@c$n`>)
output.writeLong(fileSplitterFetch.nEndPos); u{7->[=
} -oTdi0P
output.close(); p2U6B
} "[-W(=
catch(IOException e){e.printStackTrace ();} n0G@BE1Y=
catch(Exception e){e.printStackTrace ();} 4V;-*:
} U{qwhz(
k{O bm g
4]FS jVO
//读取保存的下载信息（文件指针位置） !Na@T]J
private void read_nPos() 6v74mIRn'?
{ 2I|lY>Z
try{ v}id/brl
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 8H1&=)M=
int nCount = input.readInt(); QeN7~ J
nStartPos = new long[nCount]; rp^:{6O
nEndPos = new long[nCount]; re,}}'
for(int i=0;i<nStartPos.length;i++) q6b&b^r+H
{ T9'HQu
nStartPos = input.readLong(); #3tC"2MZ
nEndPos = input.readLong(); bN6i*)}
} )?I*zc
input.close(); P,b&F
} .4l cES~
catch(IOException e){e.printStackTrace ();} ;VEKrVD
catch(Exception e){e.printStackTrace ();} <2fy(9y
} =**Q\Sl
%%#bTyF
<Ql2+ev6
private void processErrorCode(int nErrorCode) 24 .'+3
{ GvvKM=1
System.err.println("Error Code : " + nErrorCode); 9-vQn/O^D
} 9Fw NX
[:}"MdU'
UkXa mGoy3
//停止文件下载 e+<|
public void siteStop() ktRGl>J
{ *yY\d.6(
bStop = true; 2G<XA
for(int i=0;i<nStartPos.length;i++) Sn^M[}we
fileSplitterFetch.splitterStop(); t BG 9Mn
;JMmr-@
cnRgzj<ek
} bvHQ#:}H
} bR1Q77<G\
//负责部分文件的抓取 7F_N{avr
**FileSplitterFetch.java kZ]pV=\Y*
*/ ;@:-T/=
package NetFox; jP0TyhM
eKLE^`2*@
l_8ibLyo
import java.io.*; F@#p
import java.net.*; #3{{[i(;i
4#.Q|vyl]"
mg>wv[ 7
public class FileSplitterFetch extends Thread { P!IXcPKW53
)]LP8 J&
/{P-WRz>
String sURL; //File URL keG\-f
long nStartPos; //File Snippet Start Position Dd,i^,4Gj
long nEndPos; //File Snippet End Position -1~o~yGE
int nThreadID; //Thread's ID AX'-}5T=
boolean bDownOver = false; //Downing is over L "'d(MD
boolean bStop = false; //Stop identical X<pNc6
FileAccessI fileAccessI = null; //File Access interface 5sj$XA?5
=;F7h @:
FD~ UF;VQ
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ;g;1<? [
{ LU8:]zOY
this.sURL = sURL; ^QG<_Dm]
this.nStartPos = nStart; aR'~=t&;z1
this.nEndPos = nEnd; ori[[~OyB
nThreadID = id; FQE(qltf,
fileAccessI = new FileAccessI(sName,nStartPos);//定位 cct/mX2&~
} .6I'V3:Kg
:h/v"2uDN
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public void run() hy@b/Y![M
{ M;NIcM
while(nStartPos < nEndPos && !bStop) s?&S<k-=fr
{ NB86+2stu
Y"^.6
ZR"qrCSw`
try{ fC[~X[H
URL url = new URL(sURL); )O$S3ojZ
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); tA,J~|+f:
httpConnection.setRequestProperty("User-Agent","NetFox"); HD1/1?y!@q
String sProperty = "bytes="+nStartPos+"-"; WTjmU=<\
httpConnection.setRequestProperty("RANGE",sProperty); vS[\j
Utility.log(sProperty); 8rFP*K9
}n#$p{e$i
=Zsxl]h
InputStream input = httpConnection.getInputStream(); e**'[3Y
//logResponseHead(httpConnection); *65~qAd
( z F_<
\hb$v
byte[] b = new byte[1024]; Ts|;5ya5m
int nRead; [-81s!#mkw
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ^#K^WV
{ skTtGz8R[
nStartPos += fileAccessI.write(b,0,nRead); .7:ecFKk
//if(nThreadID == 1) R9D2cu,{
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 6+"gk(
} &p*rEs
X?JtEQ~>
p,uM)LD
Utility.log("Thread " + nThreadID + " is over!"); Q`4Ia<5B
bDownOver = true; }W[=O:p
//nPos = fileAccessI.write (b,0,nRead); h|ib*%P_
} rOj(THoc{
catch(Exception e){e.printStackTrace ();} AAKc8{
} ,^ dpn
} \" m&WFm
Nez '1
x{GFCy7
//打印回应的头信息 so| U&`G
public void logResponseHead(HttpURLConnection con) <X5ge>.
{ $fT#Wva-\d
for(int i=1;;i++) %da-/[
{ zwP*7u$CH
String header=con.getHeaderFieldKey(i); \%%M>4c
if(header!=null) ;XlCd[J<
//responseHeaders.put(header,httpConnection.getHeaderField(header)); Ex@}x#3
Utility.log(header+" : "+con.getHeaderField(header)); qK~]au:C
else |z&7KoYK'
break; ER@RWV2
} *P5/S8c
} {a9.0N:4
~ahu{A4Bw
CyB4apJ
public void splitterStop() <1:I[b
{ {i3=N{5b
bStop = true; x&m(h1h
} $(08!U
mv`b3 $
nPl,qcyY
} ?P#\CW
%|f@WxNrU
~x@V"rxGw
/* F[F NtZ
**FileAccess.java olXfR-2>1
*//文件访问(定位，写) | >yc|W
package NetFox; 9}42s+
import java.io.*; J~ +p7S
f.E{s*z>
qzLD
public class FileAccessI implements Serializable{ xgM\6e
#SjCKQ~
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 De>,i%`Q,D
RandomAccessFile oSavedFile; -lq`EB+
long nPos; 0m\( @2E
HzuG- V
m`Z.xIA7;
public FileAccessI() throws IOException g:p`.KuB
{ +JXn
this("",0); A_2lG!! 6
} v;}MHl
CP$,fj
~3-+~y=o~
public FileAccessI(String sName,long nPos) throws IOException ?[WUix;
{ -yu$Mm
oSavedFile = new RandomAccessFile(sName,"rw"); {!wd5C@
this.nPos = nPos; U7,.L
oSavedFile.seek(nPos); `bn@;7`X
} -*-"kzgd
Ys?0hd<cn
A8AeM`
public synchronized int write(byte[] b,int nStart,int nLen) 1-.i^Hal
{ R mo'3
int n = -1; 4<5*HpW
try{ %rEP.T\i
oSavedFile.write(b,nStart,nLen); 9VIAOky-
n = nLen; 2Qc_TgWF
} 3RcnoXX_
catch(IOException e) Wg8*;dvtM
{ %N\8!aXnf
e.printStackTrace (); ) :Px`] 5
} f'qM?GlET
lR`.V0xA
/7Q9(}
return n; _6YfPk+
} 1Vz3N/AP%?
{?A/1q4rr
8)83j6VF
} ^?A>)?Sq
E5*pD*#
0U#m7j
/* <Skf n`).
**SiteInfoBean.java xf|C{XV@H
*/ -KG1"g,2
package NetFox; gh `_{l
ofgNL .u
Y 7?q`
public class SiteInfoBean { o0dD
(&_^1
YhN:t?
private String sSiteURL; //Site's URL 58`Dcx,yJ
private String sFilePath; //Saved File's Path %/_E8GE
private String sFileName; //Saved File's Name +vV?[e
private int nSplitter; //Count of Splited Downloading File 0[8uuqV[cB
fN9uSnu
TIF =fQ
public SiteInfoBean() Wi~?2-!
{//nSplitter的缺省值为5 }b{7+ + Ah
//default value of nSplitter is 5 +]~}kvk:
this("","","",5); hxw6^EA
} gnf4H V~
U0N6\+
;:Tb_4Hr
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 8\PI1U
{ b/E3Kse?
sSiteURL= sURL; *hpS/g/3\
sFilePath = sPath; muhu` k`C
sFileName = sName; -f?,%6(1
this.nSplitter = nSpiltter; 1].m4vC
3S%/>)k
TpHzf3.I
} U_UN& /f
Ksk[sf?J&
F9r|EU#;
public String getSSiteURL() 'S9jMyZrZ
{ !?K#f?x<?
return sSiteURL; !|mzu1S
} }"/>,
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e Dpt1
public void setSSiteURL(String value) SI=7$8T5=5
{ WP^wNi ~>
sSiteURL = value; v[jg|s&6"
} 3wPUP+)c7
>3I|5kZ6
wzY{ii
public String getSFilePath() 1>umf~%Wa
{ [LV>z
return sFilePath; vSCJ xSt#e
} 8LY^>.
)d{fDwrx1
[<jU$93E
public void setSFilePath(String value) Yq{R*HO
{ V~$?]Z%_
sFilePath = value; UI~hB4V$]
} 0])[\O`j
8}Q2!,9Q
Q0g^%
public String getSFileName() S2#@j#\
{ aeEio;G1
return sFileName; '<6DLtZl
} [88PCA:
EbJc%%c
XXXQAY-,C
public void setSFileName(String value) YmHu8H_Q
{ o,/wE
sFileName = value; z0&Y_Up+5
} ,y}~rYsP%
\Y6r !D9
6yC4rX!a
public int getNSplitter() ROO@EQ#`Z
{ E+$D$a
return nSplitter; <2N=cH'
} u$D%Iz
[7,q@>:CS
_auFt"n
public void setNSplitter(int nCount) ~*e@^Nv)v
{ gIKQip<
nSplitter = nCount; 3MDs?qx>s
} HI[Pf%${
} WfYG#!}x
a/[)A _-
l;B
/* `(E$-m-~jH
**Utility.java bzECNi5^
*/ a&7uRR26
package NetFox; VDiW9]
p@oz[017/J
OMBH[_
public class Utility { 1I40N[PE)
X,}(MW
Q!r` G
public Utility() Zb:Z,O(vn
{ jVqpokWH
COHook(:
/-+hMYe
} 7j88^59
thE9fr/
//线程睡眠 K87yQOjPv
public static void sleep(int nSecond) F?qg?1vB|
{ s(r4m/
try{ KxWm63"
Thread.sleep(nSecond); -&lD0p>*g
} vx}BTH
catch(Exception e) >Sb3]$$
{ s@6Jz\<E
e.printStackTrace (); "/%o'Fq
} 2WE01D9O
} 1*.*\4xo
pnXwE-c_
//日志 sD|}?7
public static void log(String sMsg) p =-~qBw
{ IsDwa qd|
System.err.println(sMsg); ]<S{3F=
} oc#hAjB.
b.RFvq5Z
S 8)!70
public static void log(int sMsg) yI^7sf7k
{ R*2F)e\|
System.err.println(sMsg); .Ad9(s
} \9`.jB~<
} *Rxn3tR7
Rr}m(e=
gMp' S
/* 3rR1/\
**TestMethod.java `$q0fTz
*/ qqys`.
package NetFox; 9_ZGb"(Lj
\ _?d?:#RD
T1'\!6_5
public class TestMethod { 5=R]1YI~$
GInw7
ZZi|0dG4;
public TestMethod() &y7xL-xP
{ ///xx/weblogic60b2_win.exe +k[w)7Q
try{ ls~9qkAyLx
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); #)3 B
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); "2p\/VfA
SiteFileFetch fileFetch = new SiteFileFetch(bean); ~YByyJG
fileFetch.start(); dnh~An 9
} N|3#pHm@
catch(Exception e){e.printStackTrace ();} }Kn l
7k00lKA\w
@uanej0q7
} |*Oi:)qt
}Yc5U,A;
P'DcNMdw
public static void main(String[] args) DO(3hIj
{ :6/$/`I0W
new TestMethod(); ^;tB,7:*V
} lS#^v#uS
} q([{WZ:6Oq
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