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)); T.x"a$AU
} ^7>k:|7-t
for(int i=0;i<nEndPos.length-1;i++) 6 r}R%{
{ UG:S!w'
nEndPos = nStartPos[i+1]; !H/5Ud9
} AIX?840V
nEndPos[nEndPos.length-1] = nFileLength; wseb]=U
} 1K&l}/zUl
} t],5{UF
(+lCh7.
CPt62j8
//启动子线程 I("lGY
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; Kp)H>~cL
for(int i=0;i<nStartPos.length;i++) t+<?$I[
{ :7Jpt3
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ~"8D]
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), "s.]amC
nStartPos,nEndPos,i); 2SV}mK U
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); {sb2r%U!+
fileSplitterFetch.start(); rS&"UH?c7
} odaCKhdk
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), nC2e^=^
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); )Lb?ZXT3
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", >pRC$'Usx
nEndPos = " + nFileLength); WkUV)/j
// fileSplitterFetch[nPos.length-1].start(); [8v>jQ)
XSoHh-
V N<omi+4
//等待子线程结束 " .<>(bE
//int count = 0; :pXY/Pa
//是否结束while循环 u/ZV35z
boolean breakWhile = false; y)*W!]:7^>
7,7-E&d
T:=ST3#m
while(!bStop) )&vuT q'7'
{ ec3zoKtV
write_nPos(); f(UB$^4
Utility.sleep(500); L"Dos +
breakWhile = true; s8V:;$ !
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for(int i=0;i<nStartPos.length;i++) 0T2^$^g
{ Dt:NBN
if(!fileSplitterFetch.bDownOver) d.xT8l}sS
{ 76(/(v.x
breakWhile = false; zGaqYbQD
break; AwtiV-w
} p)Fi{%bc
} e:+[}I)
if(breakWhile) szUJh9-
break; Aaug0X
h@CP
66{Dyn7J~
//count++; ov\+&=IRG
//if(count>4) 4w#:?Y _\[
// siteStop(); )nlFyWXh.
} i hcSSUm
BVG.ZZR})
*nB-] w/
System.err.println("文件下载结束！"); PIHKSAnq
} 2"EaF^?\
catch(Exception e){e.printStackTrace ();} wufQyT`
} C6A!JegU
LcTTfb+<
=g|5VXW5
//获得文件长度 y#FFxSH>
public long getFileSize() '.]<lh!
{ Q%W>m0%
int nFileLength = -1; Y/T-2)D
try{ Fg0!2MKq*
URL url = new URL(siteInfoBean.getSSiteURL()); b+$E*}
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); piFZu/~Gq\
httpConnection.setRequestProperty("User-Agent","NetFox"); U+[h^M$U
|3g'~E?$
N%9?8X[5
int responseCode=httpConnection.getResponseCode(); "A0y&^4B@
if(responseCode>=400) wli H3vA_
{ 3|%058bF
processErrorCode(responseCode); >z73uKA(
return -2; //-2 represent access is error zU'7x U-
} Kw(S<~9-@
:q~5Xw/
Qe_C^(P
String sHeader; _w2%!+'
`dhBLAt
Jp= )L
for(int i=1;;i++) ez~u A4
{ aq\Fh7
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ab`9MJc;
//Utility.log(in.readLine()); n@6vCdk.
sHeader=httpConnection.getHeaderFieldKey(i); >">Xd@Wk
if(sHeader!=null) c}s#!|E0v
{ MI-S}Qoe
if(sHeader.equals("Content-Length")) #fk1'c2
{ pfw`<*e'
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); Xka+1c
break; Ti7 @{7>
} ) I(9qt>Y
} |kD69 }sG
else bYqv)_8
break; *IIA"tC
} E~VV19Bv]/
} PjXiYc&
catch(IOException e){e.printStackTrace ();} O*Y?: t
catch(Exception e){e.printStackTrace ();} A%x0'?GU
M8$eMS1
1OqVV?oz
Utility.log(nFileLength); EhW"s%Q
n5;@}Rai
C%{2 sMJz
return nFileLength; g4YlG"O[~
} e\^}PU
6RguUDRQ
sv!v`zh
//保存下载信息（文件指针位置） Ab>Kfr#
private void write_nPos() H=w):kL|
{ o|q5eUh=EY
try{ )WW*X6[k
output = new DataOutputStream(new FileOutputStream(tmpFile)); <QC7HR
output.writeInt(nStartPos.length); 87W!R<G
for(int i=0;i<nStartPos.length;i++) /8nUecr
{ 7l[@c|e
// output.writeLong(nPos); _}ii1fLv
output.writeLong(fileSplitterFetch.nStartPos); !]Qk?T~9-
output.writeLong(fileSplitterFetch.nEndPos); `#wEa'v6
} <2L,+
output.close(); ^suQ7#g
} g5"I{ol5T~
catch(IOException e){e.printStackTrace ();} zwRF-{s
catch(Exception e){e.printStackTrace ();} ,4`Vl<6
} g|->W]q@;
/5z,G r
jkta]#O
//读取保存的下载信息（文件指针位置） %'_:#!9
private void read_nPos() =Ul"{T<
{ WagL8BpLx
try{ @mv G=:k
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); A+foc5B
int nCount = input.readInt(); @1&"S7@}u
nStartPos = new long[nCount]; s8 MQ:eAP
nEndPos = new long[nCount]; NqD Hrx
for(int i=0;i<nStartPos.length;i++) .w@B )f*
{ O9_1a=M
nStartPos = input.readLong(); qm_m8
nEndPos = input.readLong(); rC!"<
} cF=WhP*f
input.close(); |[mmEYc
} sR83e|4I
catch(IOException e){e.printStackTrace ();} }2e s"
catch(Exception e){e.printStackTrace ();} Y/I)ECm
} |ka/5o
IQtQf_"e1
l4U*Lv>
private void processErrorCode(int nErrorCode) 0L8fpGJ
{ WwZ3hd
System.err.println("Error Code : " + nErrorCode); s !2Iui @
} lN:;~;z_
+a|Q)Ob
!vJ$$o6#
//停止文件下载 YG8C<g6E7
public void siteStop() 'NCqI
{ 5fiWo^s}
bStop = true; ^t7u4w!
for(int i=0;i<nStartPos.length;i++) 3T0-RP*
fileSplitterFetch.splitterStop(); o_mjI:
P;z\vq<h
6.KEe^[-
} *'A*!=5(
} D^m2iW;
//负责部分文件的抓取 @M-w8!.~
**FileSplitterFetch.java !i (V.A
*/ xl,% Z~[
package NetFox; 'V:MppQVZ.
m{RXt
C^4,L \E
import java.io.*; 8/tB?j
import java.net.*; ^Ld5<
Q[NoFZ V!
:X'B K4EN
public class FileSplitterFetch extends Thread { 8+gp"!E
fUWrR1
1irSI,j%z
String sURL; //File URL |3B<;/v5
long nStartPos; //File Snippet Start Position 8r+u!$i!H
long nEndPos; //File Snippet End Position -o"b$[sf=Z
int nThreadID; //Thread's ID rL"]m_FK
boolean bDownOver = false; //Downing is over ^8,prxaok
boolean bStop = false; //Stop identical e/+.^ '{
FileAccessI fileAccessI = null; //File Access interface ?32~%?m
|?^qsnB
%SIll
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ySiZ@i4
{ S{e3aqT#N
this.sURL = sURL; >S}X)4
this.nStartPos = nStart; j?o6>j
this.nEndPos = nEnd; SODHn9)
nThreadID = id; 9QHj$)?k,
fileAccessI = new FileAccessI(sName,nStartPos);//定位 e&i`/m5
} ESoC7d&.K{
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7DK}c]js
public void run() +(:Qf+:
{ !a\v)R
while(nStartPos < nEndPos && !bStop) pO)EYla9
{ ,!^c`_Q\>@
|n;);T(
lAo~w
try{ *mj=kJ7(
URL url = new URL(sURL); j`@`M*)GB
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Tzjv-9^V
httpConnection.setRequestProperty("User-Agent","NetFox"); (AjgLNB
String sProperty = "bytes="+nStartPos+"-"; ,']CqhL6=R
httpConnection.setRequestProperty("RANGE",sProperty); {0,6-dd5
Utility.log(sProperty); C]JK'K<7-
0>-}c>
;m.6 ~A
InputStream input = httpConnection.getInputStream(); aYk: CYQ
//logResponseHead(httpConnection); =6\^F i
eG2'W
iE;F=Rb
byte[] b = new byte[1024]; ,S(Z\[x0
int nRead; (#85<|z
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) PvW4%A@0
{ M?('VOy)
nStartPos += fileAccessI.write(b,0,nRead); zHNBX Rx
//if(nThreadID == 1) N5K2Hv<"
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); H*N{4zBB
} %52x:qGa
{=J:
A{)pzV25
Utility.log("Thread " + nThreadID + " is over!"); Vz-q7*o$S
bDownOver = true; }Cfl|t<5f
//nPos = fileAccessI.write (b,0,nRead); H13\8Te{
} s]A8C^;c
catch(Exception e){e.printStackTrace ();} 6,~1^g*
} \=|=(kt)
} ?D9iCP~~
K(lVAKiP]
8vR'<_>Q
//打印回应的头信息 sc# EL~
public void logResponseHead(HttpURLConnection con) fY78
{ ;iJxJX\+
for(int i=1;;i++) K/}x'*=
{ K]yWpW
String header=con.getHeaderFieldKey(i); *M#L)c;6
if(header!=null) .YB/7-%M[
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ywyg(8>zE
Utility.log(header+" : "+con.getHeaderField(header)); }[@Q**j(
else )~nieQEZQ
break; yQ<h>J>
} vE#8&Zq
} AkO);4A;Jd
9Nv?j=*$
suLC7x`Z
public void splitterStop() L=HnVgBs
{ bNm]h.
bStop = true; ]Z85%q^`
} 9^Web~yi#
bt.3#aj
kG}F/GN?
} !yq98I'
anfnqa8
3kF+wifsz
/* zh\"sxL
**FileAccess.java n^5Q f\o
*//文件访问(定位，写) ocUBSK|K)
package NetFox; bF+j%=
import java.io.*; g:G5'pZf
+`ov1h
b+hN\/*]
public class FileAccessI implements Serializable{ nvNF~)mu
8HIX$OX>2
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 e+VE FWz
RandomAccessFile oSavedFile; 8$ #z>
long nPos; .j**>&7L
1~LfR
|R!ozlL{}
public FileAccessI() throws IOException k"/Rjd(;
{ )/~o'M3
this("",0); ue'dI
} $\~cWpv
|k%1mE(+=s
uZ>q$ F
public FileAccessI(String sName,long nPos) throws IOException u&UmI-}
{ KT>Y^
oSavedFile = new RandomAccessFile(sName,"rw"); 'RzO`-dr
this.nPos = nPos; ^W@%(,xb
oSavedFile.seek(nPos); Y5;afU='
} Q7<VuXy
X7`-dSVE
u^CL }t*
public synchronized int write(byte[] b,int nStart,int nLen) "Jg.)1Jw
{ J2! Q09 }5
int n = -1; 2 >j0,2
try{ l"DHG`kb
oSavedFile.write(b,nStart,nLen); V3r)u\ o'
n = nLen; 'gg<)Bd
} !cM<&3/
catch(IOException e) lcjOBu
{ cL;%2TMk
e.printStackTrace (); -zqpjxU:
} 8TP~=qU
S4{vS?>j
k<+Sj h$
return n; RjPkH$u'Pj
} -1v9
5y\35kT'
>wt.)c?5
} #\QW <I#/
Y&U-d{"
\/;c^!(<
/* @fp@1n
**SiteInfoBean.java RLF6Bc
*/ DrV[1Z
package NetFox; yUpN`;
L[Z^4l_!
,pdzi9@=t
public class SiteInfoBean { ?QJx!'Y,p
iQ8{N:58DN
knG:6tQ
private String sSiteURL; //Site's URL FZ+2{wIV^
private String sFilePath; //Saved File's Path 'h'pM#D
private String sFileName; //Saved File's Name iv6G9e{cx
private int nSplitter; //Count of Splited Downloading File MZ-;'w&Z
Oy=0Hsh@x
A>upT'
public SiteInfoBean() tugIOA
{//nSplitter的缺省值为5 JWg.0d$hM
//default value of nSplitter is 5 t`|Rn9-
this("","","",5); #xu1 eX0<
} S}U_uZ$b
OhCdBO
?;`GCE
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) !J#P'x0
{ jFe8s@7
sSiteURL= sURL; f:~G)
sFilePath = sPath; RxJbQs$Ph
sFileName = sName; R0*P,~L;|
this.nSplitter = nSpiltter; XBCHJj]k
4C_1wk('
,pTZ/#vP#
} 2D"my]FnF
O*?^a7Z)4
ll$mRC
public String getSSiteURL() Z'k?lkB2i
{ }DjVZ48
return sSiteURL; 4+d(d
} XZ@+aG_%q
]6`K
@Nh}^D >j
public void setSSiteURL(String value) bIBF2m4
{ LXby(|<j
sSiteURL = value; Y&=DjKoVh
} EmUn&p%hI
w]T_%mdk
m)<+?Bv y
public String getSFilePath() ojBdUG\
{ b&h'>(
return sFilePath; D}!YF~
} MNe/H\
r]\[G6mE%
Q Rr9|p{
public void setSFilePath(String value) S m=ln)G=
{ 7#UJ444b~
sFilePath = value; 9$X" D
} R|qNyNXo[
.c<U5/
(Lz|o!>
public String getSFileName() p(GI02|n
{ b9?Vpu`?
return sFileName; =(TMcu$4`
} `]GL3cIh:
J#@+1 Nt
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public void setSFileName(String value) zD8$DG8
{ 45%D^~2~F
sFileName = value; 17l?li
} qPDRB.K|}
sLTQm*jL
~n0Exw(
public int getNSplitter() 8VG~n?y
{ Imzh`SI,
return nSplitter; 6yYd~|T.Fl
} ^a3 (QKS
Ax@7RJ||
/s(PFN8#Y
public void setNSplitter(int nCount) # E8?2]
{ ?0z/i^I
nSplitter = nCount; 6b` Jq>v
} #sv}%oV,F
} rniL+/-uU
@LU[po1I
WoSKN7*
/* w+\RSqz/
**Utility.java Y<@_d
*/ *z~J ]
package NetFox; @ K2Ncb7
!+UXu]kA
QqeF
public class Utility { j6 _w2
.Z17X_
F*:H&,
public Utility() V*6&GM&
{ TUp%Cx
"JYWsE
oye/tEMG
} cZt5;"xgr]
q| *nd!y'
//线程睡眠 p1ER<_fp
public static void sleep(int nSecond) M|$A)D1
{ Tl^)O^/
try{ DsBZ%
Thread.sleep(nSecond); `3UvKqe
} rV I-Yb
catch(Exception e) ,=}+.ax
{ lWU? R
e.printStackTrace (); Fi+,omB&
} .ityudT<
} -n$hm+S
"&kXAwe
//日志 8GT{vW9
public static void log(String sMsg) PF;`mdi-,
{ &)Iue<&2
System.err.println(sMsg); *>Zq79TG
} *wz62p
ezk:XDi4
I[v~nY~l`
public static void log(int sMsg) !iGZo2LV
{ QEq>zuz5;
System.err.println(sMsg); *s"{JrG`O
} e%&/K7I"?
} -B#>Jn#F
,O"zz7
KZTT2KsYl
/* }o#6g|"\sY
**TestMethod.java A!!W\Jt
*/ OLxiY r
package NetFox; d+Jj4OnP
]W 6!Xw)[
,Tc598D
public class TestMethod { WMd5Y`y
D[ (A`!)
'IroQ M
public TestMethod() {kgV3 [%>
{ ///xx/weblogic60b2_win.exe 3]}wZY0
try{ hbv>Jjd
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); z>X<Di&x)
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); |/-H:\5
SiteFileFetch fileFetch = new SiteFileFetch(bean); zQQ=8#]
fileFetch.start(); Ks@
} =tE7XC3X_
catch(Exception e){e.printStackTrace ();} 0WI3m2i
1FiFP5
o3~ecJ?k
} Una7O]
]N+(SU
*u4h+P
public static void main(String[] args) -mlBr63Bj
{ H_<X\(
new TestMethod(); 3"Y |RSy
} ir%?J&C+t
} bZ.q?Hlfk
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