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)); FSn&N2[D
} 8#&axg?a
for(int i=0;i<nEndPos.length-1;i++) #\X="'/
{ Yl!~w:O!o
nEndPos = nStartPos[i+1]; +IpC
} xesZ7{ o
nEndPos[nEndPos.length-1] = nFileLength; \vQjTM-7
} v;m}<3@'
} tjIT4
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//启动子线程 .*zWm
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ]-b`uYb
for(int i=0;i<nStartPos.length;i++) Q7vTTn\
{ cXY;Tw45
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), mqFo`Ee
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), c Oi:bC@
nStartPos,nEndPos,i); UZ` <D/
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); vOl<
fileSplitterFetch.start(); 1ehl=WN
} i^zncDMA
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), sa26u`?
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 4Y#F"+m.]
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", E,nxv+AQ
nEndPos = " + nFileLength); 50l!f7
// fileSplitterFetch[nPos.length-1].start(); ,-GkP>8f(
B"rfR_B2M#
f8c'`$O
//等待子线程结束 _R 6+bB$
//int count = 0; 6bXR?0$*M.
//是否结束while循环 ToVi;
boolean breakWhile = false; WzwH;!
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RZg8y+jM
while(!bStop) 5!pof\/a
{ $V0G[!4
write_nPos(); Bl"BmUn
Utility.sleep(500); =KctAR;
breakWhile = true; ra4$/@3n
7\?0d!
iE;D_m.>`O
for(int i=0;i<nStartPos.length;i++) !8V
{ yK3b^
if(!fileSplitterFetch.bDownOver) ~;#OQ[
{ RMfKM! vE
breakWhile = false; :4V8Iz 71
break; ".Q``d&X
} bI_T\Eft
} O^+H:Y|
if(breakWhile) yD-L:)@"
break; C=&rPUX{
k,mgiGrQ
c\\'x\J7
//count++; BS_ 3|
//if(count>4) f0lpwwe
// siteStop(); |pA
} g$N/pg2>cT
K_" denzT+
TOe=6Z5h
System.err.println("文件下载结束！"); /#C}1emK
} dpPu&m+
catch(Exception e){e.printStackTrace ();} ZHWxU
} 5@kNvi
oXxY$x*R1
\[57Dmo
//获得文件长度 ls928
public long getFileSize() |v6kZ0B<
{ 3m#/1=@o
int nFileLength = -1; aA|<W g
try{ XJ3p<
URL url = new URL(siteInfoBean.getSSiteURL()); Ww[Xqmg
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); $k,wA8OZ-
httpConnection.setRequestProperty("User-Agent","NetFox"); A./VO
`v|w&ty*
b-+~D9U<
int responseCode=httpConnection.getResponseCode(); 0S%xm'|N
if(responseCode>=400) l 7XeZ} S
{ nN]GO}
processErrorCode(responseCode); 1j!LK-
return -2; //-2 represent access is error [K=M;$iQ
} l[AQyR1+/
:Q=tGj\G
lzE{e6
String sHeader; T|%pvTIe
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WE*L=_zDS
for(int i=1;;i++) /qd5{%:
{ h|T_ k
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); %tOGs80_{
//Utility.log(in.readLine()); >OLKaghV.5
sHeader=httpConnection.getHeaderFieldKey(i); ,DZoE~
if(sHeader!=null) 0eP ]
{ (T9Q6\sa
if(sHeader.equals("Content-Length")) g"dq;H
{ ]+ KN9
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); L*QX21@wC
break; EDA%qNd]j
} S#{jyU9 ]
} <0w"$.K#3
else cR*5iqA
break; 2:6W_[7l!
} :< d.
} I0qSx{K
catch(IOException e){e.printStackTrace ();} 0'QX*xfa>
catch(Exception e){e.printStackTrace ();} J2BCaAwEP,
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<?>1eU%
Utility.log(nFileLength); (\8~W*ej"
RXD*;B$v
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return nFileLength; p|gzU$FWbk
} x* 9 Xu"?
J\@W+/#dF
!2o1c
//保存下载信息（文件指针位置） MP3Vo|}3
private void write_nPos() i!a.6Gq
{ Sf>#Zqj/
try{ $0mR_pA\fW
output = new DataOutputStream(new FileOutputStream(tmpFile)); .DX-biX,
output.writeInt(nStartPos.length); `B A'a" $
for(int i=0;i<nStartPos.length;i++) F{*h~7D-|
{ s;ivoGe}
// output.writeLong(nPos); 6L!/#d0
output.writeLong(fileSplitterFetch.nStartPos); \2c3Nsra
output.writeLong(fileSplitterFetch.nEndPos); x_+-TC4IXn
} k',#T932x1
output.close(); %4QpDt
} Hh1]\4D,4
catch(IOException e){e.printStackTrace ();} F<+!28&h
catch(Exception e){e.printStackTrace ();} /=(PMoZu
} TlEd#XQgf&
j%`% DQ
s0To^I
//读取保存的下载信息（文件指针位置） _t/~C*=:=
private void read_nPos() 2bnYYQ14:
{ z%Eok
try{ (B^rW,V[R
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); M/mm2?4
int nCount = input.readInt(); 7@1GSO:Yf
nStartPos = new long[nCount]; !\}X?Gf
nEndPos = new long[nCount]; B" 0a5-pkr
for(int i=0;i<nStartPos.length;i++) L[cP2X]NQ
{ N;q)[Dr
nStartPos = input.readLong(); cFZcBiw
nEndPos = input.readLong(); *8I"7'xh
} 'nT#c[x[0
input.close(); QG=K^g
} II'"Nkxd
catch(IOException e){e.printStackTrace ();} 9Rm\@E [
catch(Exception e){e.printStackTrace ();} I !J'
} jf^BEz5
EvKzpxCh
rQD^O4j R
private void processErrorCode(int nErrorCode) ]<*-pRN
{ ,x=S)t
System.err.println("Error Code : " + nErrorCode); <5 }
} vk4Q2P
r,HIoeAKP
q"e]\Tb=we
//停止文件下载 $3=S\jyfK
public void siteStop() nCS" l5
{ `*ALb|4ilG
bStop = true; c[>xM3=e^q
for(int i=0;i<nStartPos.length;i++) NXCvS0/h
fileSplitterFetch.splitterStop(); %6W%-`
{[)n<.n[g
vB%os Qm
} gkmV;0
} .]e_je_
//负责部分文件的抓取 )`BKEaf
**FileSplitterFetch.java p/U{*i]t
*/ 4:9N]1JCb
package NetFox; mIZ6[ ?
1{AK=H')
jx{wOb~oO)
import java.io.*; |[)n.N65=
import java.net.*; Y:R*AOx
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public class FileSplitterFetch extends Thread { ubv>*iO
Y$5uoq%p3A
|->CI
String sURL; //File URL tE#;$Ss
long nStartPos; //File Snippet Start Position \^1S:z
long nEndPos; //File Snippet End Position ox*>HkV
int nThreadID; //Thread's ID Ae[fW97
boolean bDownOver = false; //Downing is over SLW|)Q24
boolean bStop = false; //Stop identical {2)).g
FileAccessI fileAccessI = null; //File Access interface FP'-=zgc
Xp.$FJ1)
w{*PZb4
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException `&9iC 4P
{ E&N~h|CL
this.sURL = sURL; 3$_JNF`
this.nStartPos = nStart; dmWCNeja.
this.nEndPos = nEnd; aJQzM
nThreadID = id; fC".K Yjp
fileAccessI = new FileAccessI(sName,nStartPos);//定位 !nsx!M
} LS$zA>:
+s;>@j()V
O6ph_$nt.
public void run() [MuZ^'dR
{ M1icj~Jr
while(nStartPos < nEndPos && !bStop) !zfKj0^
{ /i~x.i3
!QpOrg
}xry
try{ x"n++j
URL url = new URL(sURL); & 'CUc/,
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); npd:aGx
httpConnection.setRequestProperty("User-Agent","NetFox"); 15S&,$1&
String sProperty = "bytes="+nStartPos+"-"; }K5okxio
httpConnection.setRequestProperty("RANGE",sProperty); I^nDO\m <
Utility.log(sProperty); \(RD5@=!4#
S1[, al
"x vizvR
InputStream input = httpConnection.getInputStream(); U:z5`z!
//logResponseHead(httpConnection); ]q~bi<E9W
@qpj0i+>*
(:I]v_qEYS
byte[] b = new byte[1024]; Qvty;2$o@
int nRead; T 5F)
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) %fnG v\uI
{ Y1ks'=c>
nStartPos += fileAccessI.write(b,0,nRead); W*Si"s2
//if(nThreadID == 1) jfiUf1Mj
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 9Z21|5
} JA*+F1s
0'HQ=pP
ps;dbY*s6
Utility.log("Thread " + nThreadID + " is over!"); %E5b}E#
bDownOver = true; 16>D?;2o(
//nPos = fileAccessI.write (b,0,nRead); ,kf.'N
} ^|SiqE
catch(Exception e){e.printStackTrace ();} 2]<.m]
} yVp,)T9
} @dUN3,}
?5jLN&A3 G
Se_]=>WI
//打印回应的头信息 '$c9S[
public void logResponseHead(HttpURLConnection con) `yP`5a/
{ g60k R7;\
for(int i=1;;i++) l2kGFgc
{ DJ DQH\&
String header=con.getHeaderFieldKey(i); #N"u 0
if(header!=null) lWecxD$
//responseHeaders.put(header,httpConnection.getHeaderField(header)); tS>^x
Utility.log(header+" : "+con.getHeaderField(header)); LP=y$B
else R*!s'R
break; JEk'2Htx
} <:Mz2Rg
} aU~?&]
E%DT;1
qY$ [2]
public void splitterStop() ] j8bv3
{ d!UxFY@
bStop = true; co~NXpqg
} yQ$]`hr;
7FJ4;HLQ
c-PZG|<C[
} TZ+ p6M8G
araXE~Ac
7f}uRXBV$A
/* 8]Tv1Wc
**FileAccess.java ,~=]3qmbR
*//文件访问(定位，写) - om9 Z0e
package NetFox; .>eRX%
import java.io.*; NhCucSU<K
P1Z"}Qw
p20JUzy
public class FileAccessI implements Serializable{ v7SYWO#
n|{#5#
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 SDC'S]{ew
RandomAccessFile oSavedFile; M2-`p
long nPos; SAdE9L =d
eb}P/
*!ng)3#
public FileAccessI() throws IOException Ps>:|j+
{ 9OV@z6
this("",0); YR*gOTD
} (jA5`4>u
L2,2Sn*4i
Z3weFbCH
public FileAccessI(String sName,long nPos) throws IOException !8[T*'LJ-
{ 4`,7tj
oSavedFile = new RandomAccessFile(sName,"rw"); DtFHh/X
this.nPos = nPos; L7Hv)
oSavedFile.seek(nPos); v@soS1V!
} o0]YDX@T
nj'5iiV`]
KCW2 UyE]
public synchronized int write(byte[] b,int nStart,int nLen) Q(]m1\a
{ w8w0:@0(
int n = -1; l)vC=V6MG
try{ mpug#i6q
oSavedFile.write(b,nStart,nLen); Bd <0}
n = nLen; t\hnnu`Pq
} W06#|8,{v
catch(IOException e) Zs />_w}
{ &F uPd}F
e.printStackTrace (); a1~|?PCbY
} J<;io!
&J&'J~N
hNM8H
return n; 6qHD&bv\%C
} Tj#S')s8
< j:\;mi;
12z!{k7N
} oj - `G
le\-h'D
*,4rYb7I w
/* $G`CXhbl
**SiteInfoBean.java \ saV8U7B
*/ pOXI*0_g.
package NetFox; ?"mZb#%
lc[6Mpi7s[
nsRCDUCi
public class SiteInfoBean { xqzeBLU
.DhI3'Jrl
@01.Pd
private String sSiteURL; //Site's URL iHGVR
private String sFilePath; //Saved File's Path UeO/<ml3>J
private String sFileName; //Saved File's Name VKDOM0{V
private int nSplitter; //Count of Splited Downloading File P}}G9^
d\JaYizp
\{@m
public SiteInfoBean() Eo6N'h>h
{//nSplitter的缺省值为5 =G:Krc8w@
//default value of nSplitter is 5 fA6IW(_bi
this("","","",5); rJpr;QKf%
} 6}TunR
*~)6 sm
E:x@O8F
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) g:M;S"U3*Y
{ K<e #y!
sSiteURL= sURL; yMz#e0k
sFilePath = sPath; m"n74cxS
sFileName = sName; fWmc$r5n](
this.nSplitter = nSpiltter; ,2fi`9=\
]ZcivnN#
x vs=T
} .jCGtR )%
* @4@eQF
9fEe={ B+
public String getSSiteURL() 'Gn>~m
{ T]De{nHu
return sSiteURL; SA +d4P_T
} +c))fPuV
)XDBK*!
YRlfU5
public void setSSiteURL(String value) KEOk%'c,
{ +>#SNZ[
sSiteURL = value; [[ie
} GQtNk<?$I
i!%bz
8gP1]xD
public String getSFilePath() (SyD)G\rj
{ i<"lXu
return sFilePath; ?}KRAtJ8
} D5lQ0_IeW
NfvPE]S
!q2zuxq!R
public void setSFilePath(String value) D.a>i?W
{ 61S;M8tNv
sFilePath = value; Y"mFUW4
} Keh=>K)T
9-;-jnDy
4aS}b3=n
public String getSFileName() dEJqgp}\p
{ A9.TRKb=8
return sFileName; ^O_Z5NbC3
} spV7\Gs.@
|8k1Bap`z
sF {,n0<8
public void setSFileName(String value) `9^tuR,
{ |{N{VK
sFileName = value; +K1M&(
} G,)zn9X
j}^w:W76
2<@2_wSJ
public int getNSplitter() Y:!L
{ ?@rd,:'dE
return nSplitter; {XOl &
} '0HOL)cIz
cU6*y!}9
Ek L2nI
public void setNSplitter(int nCount) Mh)?A/e
{ D~C'1C&W
nSplitter = nCount; Y*NzY*V\
} VE+H! ob A
} uV5uZ
<8:h%%$?
<F7a!$zQ
/* ' h7Faj
**Utility.java QF>T)1&J[7
*/ &*v\t\]
package NetFox; UMGiJO\yH
7zG r+Px
$r!CQ2S
public class Utility { ~7 i{~<?
T`x|=}
{srP3ll P
public Utility() `;UWq{"
{ pQiC#4b
]DNPG"
]}v]j`9m%
} b}K,wAx
p[Po*c.b
//线程睡眠 hP"2X"kz&
public static void sleep(int nSecond) {:1j>4m2
{ i\sBey ND"
try{ >bW=oTFz
Thread.sleep(nSecond); E.K^v/dNdq
} joe)b
catch(Exception e) d/; tq
{ cw<IL
e.printStackTrace (); *z~,|DQ(A
} Cab.a)o
} t7]j6>MK3q
F rckA
//日志 & P-8_I
public static void log(String sMsg) *JJ8\R&P0
{ jYp!?%!
System.err.println(sMsg); Jq/itsg
} {+67<&g
~IhM(Q*mO!
m]n2wmE3n
public static void log(int sMsg) "Vp nr +6
{ QEr<(wM-y
System.err.println(sMsg); :H]d1
} 4#IT" i
} 2VN].t:
#gC[L=01
?EFRf~7JP
/* G[k3`
**TestMethod.java e0`z~z]6&
*/ hY&Yp^"}]^
package NetFox; k6bct@7
Q!+AiSTU
OFtaOjsyUa
public class TestMethod { jqaX|)8|$
m'"r<]pB*4
Skt-5S#
public TestMethod() wMVUTm
{ ///xx/weblogic60b2_win.exe 91]|4k93
try{ WoTeIkM9
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); gv`_+E{P
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 5 bI:xL}
SiteFileFetch fileFetch = new SiteFileFetch(bean); K%J?'-
fileFetch.start(); `58%&3lp
} Yz/Blh%V
catch(Exception e){e.printStackTrace ();} ^\ [p6>
leC!Yj
[.}qi[=n
} 1$0Kvvg[
vfkF@^D
2d.$V,U<
public static void main(String[] args) *Ypn@YpSp
{ t;o\"H
new TestMethod(); F'K >@y
} cr!8Tp;2A
} P*&[9)d6
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