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)); tz^2?wO
} ',_E;(
for(int i=0;i<nEndPos.length-1;i++) Tr6J+hS
{ %&Fsk]T%:
nEndPos = nStartPos[i+1]; z+5ZUS2~&
} `)aIFAW
nEndPos[nEndPos.length-1] = nFileLength; -%G}T}"_
} t| cL!
} If*+yr|
qH=<8Iu
Nn/f*GDvK
//启动子线程 HxAN&g*:
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; fOUW{s
for(int i=0;i<nStartPos.length;i++) -qJ%31Mr#
{ :lfUVa{HN
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), prdc}~J8{
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), RV_(T+
nStartPos,nEndPos,i); %U uVD
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); cWU9mzsE
fileSplitterFetch.start(); *+UgrsRk
} E2nsBP=5C
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), <i$ud&D
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ob_*fP
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", pYBY"r
nEndPos = " + nFileLength); <E&8g[x6
// fileSplitterFetch[nPos.length-1].start(); 6OPYq*|
,_iR
>^Z==1
//等待子线程结束 C$x r)_
//int count = 0; @ L=dcO{r
//是否结束while循环 K2o\+t
boolean breakWhile = false; US'rhSV
9 *+X^q'
~lQ<#*wl
while(!bStop) tb1w 6jaU
{ -Pt']07E
write_nPos(); = }!4%.$
Utility.sleep(500); IQ]tcSQl
breakWhile = true; X+%5q =N
s[n*fV']A
1w$X;q"
for(int i=0;i<nStartPos.length;i++) 05ZF>`g*
{ 8WP|cF]
if(!fileSplitterFetch.bDownOver) pIhy3@bY
{ "q]r{0
breakWhile = false; g;eoH
break; 1"fbQ^4`
} T!YfCw.HZ
} ?.~hex#M@
if(breakWhile) = lMs1}S9
break; T*"*##c
LcW:vV|'K
7Ap==J{a
//count++; Q~-MB]'
//if(count>4) RQ*oTsq
// siteStop(); EG#mNpxE
} *%aWGAu:
Z[GeU>?P
5<77o|
System.err.println("文件下载结束！"); KM9)
} *Z}9S9YtN
catch(Exception e){e.printStackTrace ();} gNaB^IY
} 8r\;8all
Y7GHIzX
;56mkP
//获得文件长度 0ME.O+
public long getFileSize() 2S@aG%-)
{ gw_]Y^U
int nFileLength = -1; Ch0t'
try{ gCP f1z
URL url = new URL(siteInfoBean.getSSiteURL()); ZQN%!2
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); p->b Vt
httpConnection.setRequestProperty("User-Agent","NetFox"); +'ADN!(B_
\2OjIEQQ
9>!B .Z?!#
int responseCode=httpConnection.getResponseCode(); %|o2d&i
if(responseCode>=400) ~&%&Z
{ )Rj,PF-9Z[
processErrorCode(responseCode); Y q(CD!
return -2; //-2 represent access is error aTi,gJ;*
} @w @SOzS)
%<rV~9:
D:.1Be`Tv
String sHeader; zi?G wh~
PCX X[N
h7 c
for(int i=1;;i++) .[:2M9Rx
{ VI(2/**
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); *U:0c ;h
//Utility.log(in.readLine()); !wr2OxK*
sHeader=httpConnection.getHeaderFieldKey(i); c0.? d]
if(sHeader!=null) !McRtxq?~
{ `Qxdb1>mjY
if(sHeader.equals("Content-Length")) .?dYY;P
{ W_FN*Er
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); !K8V":1du#
break; )ad6>Y
} T(q/$p&q
} .]y"04@]
else )o N#%%SB<
break; *$*V#,V-
} b3^d!#KVM
} JL:\\JT.
catch(IOException e){e.printStackTrace ();} ,k+F8{Q.
catch(Exception e){e.printStackTrace ();} ?:c:D5N
BW5!@D2
1 R,?kUa
Utility.log(nFileLength); D]*<J"/]d
q7aH=dhw
m5kt O^EU
return nFileLength; GI[XcK^*w
} 6$x9@x8
5$<Ozkj(
g?>V4WF
//保存下载信息（文件指针位置） T@gm0igW/;
private void write_nPos() ?D9>N'yH8
{ O]-s(8Oo3
try{ 2/f!{lz](
output = new DataOutputStream(new FileOutputStream(tmpFile)); BQF7S<O+
output.writeInt(nStartPos.length); "iPX>{'En
for(int i=0;i<nStartPos.length;i++) mY0FewwTy
{ *]+5T-R% $
// output.writeLong(nPos); rpMjDjW
output.writeLong(fileSplitterFetch.nStartPos); Og/@w&
output.writeLong(fileSplitterFetch.nEndPos); .EdQ]c-E=
} >O/1Lpl.3
output.close(); %P HYJc
} ?8TIPz J
catch(IOException e){e.printStackTrace ();} OiJz?G:m
catch(Exception e){e.printStackTrace ();} f;cY&GC
} 7CV}QV}G
S0jYk(
qN@0k>11?
//读取保存的下载信息（文件指针位置） RDsBO4RG
private void read_nPos() 6sz:rv}
{ c]>LL(R-7)
try{ #8sv*8&
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); B4{clI_i
int nCount = input.readInt(); W_Eur,/`
nStartPos = new long[nCount]; k:*(..!0z
nEndPos = new long[nCount]; iVAAGZ>am
for(int i=0;i<nStartPos.length;i++) H?$gHZPI
{ (GB*+@
nStartPos = input.readLong(); :7 OhplI
nEndPos = input.readLong(); \ ix&U
} ;^9y#muk
input.close(); 'FN+BvD
} "|6763.{4
catch(IOException e){e.printStackTrace ();} {L.=)zt>
catch(Exception e){e.printStackTrace ();} Ers8J V
} G{4lgkyy
6o=Q;Mezl
_n=,H
private void processErrorCode(int nErrorCode) -E,p[Sp
{ CI+@GXY
System.err.println("Error Code : " + nErrorCode); -YJ4-]Z
} b1Fd]4H3P
y6`zdB
Z?j4WJy-[
//停止文件下载 2YhtD A
public void siteStop() :WHbwu,L$
{ 1vUW$)?X
bStop = true; =+"=|cQ
for(int i=0;i<nStartPos.length;i++) K3-Cuku
fileSplitterFetch.splitterStop(); vD3j(d
SU>cJ*
_8ubo\M~
} /& wA$h
} P^J#;{R
//负责部分文件的抓取 D+('1E?
**FileSplitterFetch.java c!Wj^
*/ b|E1>TkY
package NetFox; *7UDTgY
-I*NS6
%h"%G=:
import java.io.*; Y2>0Y3yM
import java.net.*; Vk?US&1q}
P-)`FB
}4XXNYH
public class FileSplitterFetch extends Thread { zot_ jSV
$Fik]TbQp
,Uu#41ZOKL
String sURL; //File URL 6):iu=/i/
long nStartPos; //File Snippet Start Position k\A[p\
long nEndPos; //File Snippet End Position M$MFUGS'
int nThreadID; //Thread's ID &hSF
boolean bDownOver = false; //Downing is over FC }r~syqA
boolean bStop = false; //Stop identical :!<U"AC
FileAccessI fileAccessI = null; //File Access interface Rb l4aB+
qY$]^gS
H&h"!+t(#
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException l$DQkbOj
{ R~H+.Vh
this.sURL = sURL; \Ws$@J-M
this.nStartPos = nStart; -$tf`
this.nEndPos = nEnd; WNWtQ2]
nThreadID = id; 4$MV]ldUI
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ,@r 0-gL
} 'q, L*
!B:wzb_
9KDm<Q-mf
public void run() ;k5B@z/<S
{ %hV]vm
while(nStartPos < nEndPos && !bStop) {<L|Z=&k`
{ x}X hL
|7@@~|A
*D:uFo,xn
try{ *@zya9y9q
URL url = new URL(sURL); vd#BT$d?
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); `|f1^C^
httpConnection.setRequestProperty("User-Agent","NetFox"); $.T\dm-
String sProperty = "bytes="+nStartPos+"-"; B f"L;L
httpConnection.setRequestProperty("RANGE",sProperty); S7f"\[Aw
Utility.log(sProperty); ve@E.`
b_>x;5k
u]jvXPE6
InputStream input = httpConnection.getInputStream(); z-G*:DfgH
//logResponseHead(httpConnection); =v49[i
MKZq*
>o|.0aw<
byte[] b = new byte[1024]; B> V)6\
int nRead; w*krPaT3
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) N`rz>6,k1
{ 6<{XwmM
nStartPos += fileAccessI.write(b,0,nRead); MoMxKmI
//if(nThreadID == 1) WI\jm&H r
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); +5qY*$dn
} ,B,:$G<
vG#,J&aW
84f^==Y
Utility.log("Thread " + nThreadID + " is over!"); R&FO-{S
bDownOver = true; `<IaQY
//nPos = fileAccessI.write (b,0,nRead); e(Y5OTus
} a}5/?/
catch(Exception e){e.printStackTrace ();} VkZ3Q7d
} !]2`dp\!
} 9Z lfY1=
$3yn-'o'A
%{ +>\0x
//打印回应的头信息 `IH*~d]
public void logResponseHead(HttpURLConnection con) 4v;KtD;M
{ ]Pf!wv
for(int i=1;;i++) ` 3h,Cy^
{ Zx U?d
String header=con.getHeaderFieldKey(i); v9XevLs
if(header!=null) =} flmUv~
//responseHeaders.put(header,httpConnection.getHeaderField(header)); <P0&!yN
Utility.log(header+" : "+con.getHeaderField(header)); $_Q]3"U
else a|kEza,]
break; $64sf?aZ>#
} ?d`j}
} (\M+E tU<9
HL~DIC%
LXf*
public void splitterStop() ~w"e 2a
{ o>e-M
bStop = true; yt1dYF0Xq
} P`OZoI$bV
K?eY<L
.'zcD^
} `[F[0fY-
)| 0(#R
21 N!?DR
/* 7;$[s6$
**FileAccess.java %&pd`A/
*//文件访问(定位，写) y_{fc$_&
package NetFox; M=#g_*d
import java.io.*; tqzr+
~vB dq Yj
O>[B"mMt
public class FileAccessI implements Serializable{ 2}U:6w
I;+>@Cn(g<
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 *s$:"g-
RandomAccessFile oSavedFile; 37 d-!
long nPos; j71RlS73
gIY]hC.
Dn@Sjsj>
public FileAccessI() throws IOException l,:>B-FV
{ 5~{s-Ms
this("",0); ie}?}s
} !a^'Jbb
*nlDN4Y[
Yge}P:d9
public FileAccessI(String sName,long nPos) throws IOException h]DzX8r}
{ j6#Vwcr
oSavedFile = new RandomAccessFile(sName,"rw"); To =JE}jzo
this.nPos = nPos; _ pO1XM
oSavedFile.seek(nPos); Ug8>|wCE
} <Y+>a#T
xbD]EC
`@^s}rt+
public synchronized int write(byte[] b,int nStart,int nLen) uQiW{Kja2
{ s7s@!~
int n = -1; (x140_TH~
try{ T0"q,lrdxV
oSavedFile.write(b,nStart,nLen); %OJq(}
n = nLen; MQq!<?/
} Esdw^MGL2
catch(IOException e) aPm2\Sq$
{ O:jaA3
e.printStackTrace (); `2,F!kCt
} ,L-G-V+
\T {<{<n
Ti&v9re%wO
return n; #PQhgli
} ky I~
RSBk^
zszx~LSvIT
} @waY+sqt=
S=qx,<J 39
{~EPP .
/* |vgYi
**SiteInfoBean.java Zb$P`~(%
*/ ?JMy
package NetFox; %a|m[6+O
jf=\\*64r4
E(Zm6~
public class SiteInfoBean { rT';7>{g
{ZKXT8'
!#dp[,nk
private String sSiteURL; //Site's URL `u$lSGl
private String sFilePath; //Saved File's Path hE;BT>_dn
private String sFileName; //Saved File's Name !YIW8SP)
private int nSplitter; //Count of Splited Downloading File H0-v^H>^
l09DH+
i/RA/q
public SiteInfoBean() }Apn.DYbbf
{//nSplitter的缺省值为5 F.-:4m(Z
//default value of nSplitter is 5 1"~$(@oxG
this("","","",5); 'Xu3]'m*
} j.+}Z |
s=hao4v7z
qqSFy>`P
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ahg]OWn#
{ Z4369
sSiteURL= sURL; 2X6L'!=
sFilePath = sPath; nx@,oC4
sFileName = sName; Y'76!Y
this.nSplitter = nSpiltter; GuKiNYI_
`NCH^)
Dr5AJ`y9A
} >\[|c
G#j~8`3X
'mk_s4J
public String getSSiteURL() $y,tR.5.)[
{ |f2bb
return sSiteURL; LL+PAvMg
} 75eZhs[b
F<J`1 :
o8fY!C)
public void setSSiteURL(String value) }A&I@2d
{ ]MnQ3bWq"j
sSiteURL = value; =)nJ'}x
} 6Cgc-KNbk
.q|k459oi
Lmw4
public String getSFilePath() Q:8t1ZDo
{ W{fNZb'
return sFilePath; Z31a4O
} }70A>JBw
tv%B=E!r
#3_ @aq*
public void setSFilePath(String value) '3fN2[(
{ ~nb1c:F
sFilePath = value; l<:\w.Gl
} yaYJmhG
xc,Wm/[
SE6c3
public String getSFileName() 7KN+ @6!x
{ Xo3@-D_c!c
return sFileName; z@v2t>@3k
} VM<$!Aaz
sBLOrbo
{'yr)(:2M
public void setSFileName(String value) s&1}^'|
{ v\D.j4%ij
sFileName = value; e?+&2zMq
} wY"BPl]b
Y6m:d&p=}
2yV^'o)
public int getNSplitter() P4fnBH4OQ
{ ;cGY
return nSplitter; >1$Vh=\OI
} 4@QR2K|
<[?ZpG
+mC?.B2D
public void setNSplitter(int nCount) DA>TT~L
{ [F 24xC+
nSplitter = nCount; g0#w 4rGF)
} pd-I^Q3-
} c^stfFE&
zBc |gx
!o\e/HGc!
/* hG>kx8h
**Utility.java 3 J5lz~6
*/ .mplML0oW
package NetFox; u{S"NEc
/Ow@CB
myF/_o&Ty
public class Utility { KBa0
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CW -[c
public Utility() F<DXPToX%
{ G\K!7k`)!
Nka 3H7`
m .R**g
} 0+/ew8~$
3sp-0tUE
//线程睡眠 B_*Ayk
public static void sleep(int nSecond) OoQLR
{ ~ 1~|/WG
try{ `eeA,K_
Thread.sleep(nSecond); >4J(\'}m|
} xtut S
catch(Exception e) ~SS3gLv
{ q@1xYz:J
e.printStackTrace (); SGu`vN]
} Z>pZ|
} Q 3/J@MC
vsJDVJ +=
//日志 <`WcI`IAb
public static void log(String sMsg) u:H:N]
{ ?in)kL
System.err.println(sMsg); h4Xz"i{z
} e m
}b]eiPWN
T3@34}*
public static void log(int sMsg) t9)S^: 0
{ AcHeZb8b
System.err.println(sMsg); IyAD>Q^
} @M"( r"ab
} M0$E_*
1x8wQ/p|
^bq,+1;@Q
/* )iFXa<5h
**TestMethod.java J$lfI^^
*/ %M:$ML6b<
package NetFox; !+]KxB
eJeL{`NS
KDb`g}1Q
public class TestMethod { 0{
3-'3w,
]^,!;do
public TestMethod() mF4y0r0
{ ///xx/weblogic60b2_win.exe .A0fI";Q
try{ qae|?z
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Cj$:TWYIh[
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); rAE5.Q!u
SiteFileFetch fileFetch = new SiteFileFetch(bean); @8$z2
fileFetch.start(); u60RuP&
} i.\ e/9]f
catch(Exception e){e.printStackTrace ();} iB`EJftI!
PkLNIp1
J 5xMA-
} `3`.usw
8H|ac[hXK2
_3.rPS,s
public static void main(String[] args) )?pnV":2Y
{ UmY{2 nzY
new TestMethod(); `F3wO!
} E^$8nqCL:
} I?^(j;QpS
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