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)); Q?-uJ1J
} scR+F'M
for(int i=0;i<nEndPos.length-1;i++) 30L/-+r1
{ Tg6nb7@P
nEndPos = nStartPos[i+1]; zjwo"6c>
} x DX_s:A
nEndPos[nEndPos.length-1] = nFileLength; R5'_il
} k1M?6TW&
} t:qPW<wc
2%t!3F:
9XW[NY#)#
//启动子线程 Aq{7WA
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; K]dX5vJw'
for(int i=0;i<nStartPos.length;i++) jp+#N pH
{ <^B!.zQ
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), LZrkFkiC
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), (JeRJ4
nStartPos,nEndPos,i); _ +A$6l
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); K@;ls
fileSplitterFetch.start(); iuWw(dJk
} <zF/at
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), b;t b&o
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); q|.K&@_'K
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", Y'M}lv$sa
nEndPos = " + nFileLength); j:'!P<#
// fileSplitterFetch[nPos.length-1].start(); r2>y !Q?
\DRYqLT`
F` ]s
//等待子线程结束 Xc7Qu?}
//int count = 0; p|R]/C0f
//是否结束while循环 Rj{D#5
boolean breakWhile = false; QD*(wj
-vBk,;^>
({p@Ay
while(!bStop) ,v*<yz/
{ ED R*1!d
write_nPos(); d)jX%Z$LC
Utility.sleep(500); o$bD?Zn
breakWhile = true; dG'5: ,n/
C$fQ[@
qAR}D~t
for(int i=0;i<nStartPos.length;i++) K6z-brvw"
{ VWcR@/3
if(!fileSplitterFetch.bDownOver) 1F }mlyS
{ E9n7P'8
breakWhile = false; %#b+ =J
break; ^tFgkzXm
} YM]ZL,8
} NpF}~$2
if(breakWhile) A49HYX-l
break; }-ysP$
j8#B
>l|dLyiae
//count++; YfOO]{x,X
//if(count>4) O{`r.H1',
// siteStop(); CF+:9PG
} .=-K7.X.)
b-,]21
F6\r"63
System.err.println("文件下载结束！"); 'aW<C>
} E>6:59+
catch(Exception e){e.printStackTrace ();} e8<[2J)P&
} zhFk84
BFyVq
$2\k| @)s
//获得文件长度 WXC}Ie
public long getFileSize() } ~#^FFe
{ ;R.l?Bg
int nFileLength = -1; 2d Px s:8&
try{ "Crm\UI6
URL url = new URL(siteInfoBean.getSSiteURL()); !t92_y3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); bAqaf#}e
httpConnection.setRequestProperty("User-Agent","NetFox"); iv62Fs'
l<#*[TJ
a uz2n
int responseCode=httpConnection.getResponseCode(); 1u0NG)*f
if(responseCode>=400) ,zY!EHpx
{ Zf%6U[{ T
processErrorCode(responseCode); ;qT7BUh(%
return -2; //-2 represent access is error [{!5{k!
} )51H\o
8y, ]>n
="*8ja-K
String sHeader; O;*.dR
p%6j2;D
-N[Q*;h|
for(int i=1;;i++) `[5QouPV
{ sj?7}(s
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); I*^3 Z
//Utility.log(in.readLine()); Qv@Z#
sHeader=httpConnection.getHeaderFieldKey(i); |%~sU,Y\(
if(sHeader!=null) .5x+FHu7
{ /N&)r wc
if(sHeader.equals("Content-Length")) Z[{: `
{ enGjom
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); -dn\*n5
break; h .Iscr^~
} =a.avOZ
} ^J=l] l
else xPi/nWl`|
break; `?ijKZ}y5
} U:.
} Mo2b"A;}|
catch(IOException e){e.printStackTrace ();} z2QZ;ZjvRS
catch(Exception e){e.printStackTrace ();} Ya)s_Zr7
HjAQF?;V
L)o7~M
Utility.log(nFileLength); g.d%z
EO5k?k[*
)R2BTE:
return nFileLength; Vuqm{bo^
} /WJ*ro]Hd$
OxraaN`
Bld$<uU
//保存下载信息（文件指针位置） *XK9-%3
private void write_nPos() MMfcY 3#%
{ oZV=vg5Dq
try{ =wW3Tr7~
output = new DataOutputStream(new FileOutputStream(tmpFile)); ![BQ;X
output.writeInt(nStartPos.length); .hxcx>%
for(int i=0;i<nStartPos.length;i++) |E)Es!dr
{ m18If
// output.writeLong(nPos); xNh#=6__9
output.writeLong(fileSplitterFetch.nStartPos); dik+BBu5z
output.writeLong(fileSplitterFetch.nEndPos); N@>,gm@UU
} +)Pv6Zog[
output.close(); ^vjN$JB
} R;_U BQ)
catch(IOException e){e.printStackTrace ();} x^|J-
catch(Exception e){e.printStackTrace ();} YEWHr>&Z
} w-%H\+J
:_q
~iZMV ?w
//读取保存的下载信息（文件指针位置） btK| U
private void read_nPos() .f V-puE
{ I"]5B
try{ JxP=[>I
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); oAkF
int nCount = input.readInt(); ?[K+Ym+
nStartPos = new long[nCount]; 3 G?^/nB
nEndPos = new long[nCount]; pH%cbBm
for(int i=0;i<nStartPos.length;i++) Ab<4F7
{ -k p~pe*T
nStartPos = input.readLong(); ,))UQ7N
nEndPos = input.readLong(); {P_~_5o_
} >69+e+|I
input.close(); $Wy7z^t
} an 3"y6.8
catch(IOException e){e.printStackTrace ();} @83h/Wcxd
catch(Exception e){e.printStackTrace ();} uw@z1'D[i"
} n2Oi< )
HN\Zrb
>o=3RB=Fh
private void processErrorCode(int nErrorCode) _be*B+?2t
{ W%f:+s}cI
System.err.println("Error Code : " + nErrorCode); s7CoUd2
} \]U@=w
\*H/YByTb
dF{3~0+,
//停止文件下载 j[XA"DZR<
public void siteStop() 8z^?PZ/
{ K2TO,J3 E
bStop = true; {R7>-Y[4)2
for(int i=0;i<nStartPos.length;i++) nu] k<^I5|
fileSplitterFetch.splitterStop(); b'^OW
${#5$U+kI
^j?\_r'j
} }ZEh^zdz8
} q!k F
//负责部分文件的抓取 AF1";duA
**FileSplitterFetch.java <R7*00
*/ `)F lb|da
package NetFox; eB78z@
@.gT&Hq
_F^k>Lq&d
import java.io.*; n*^g^gp
import java.net.*; ei;wT
oh`I$
`e0U-W]kF
public class FileSplitterFetch extends Thread { ^CTgo,uf6H
p3:x\P<|
cve(pkl
String sURL; //File URL fMr6ZmB
long nStartPos; //File Snippet Start Position owTW_V
long nEndPos; //File Snippet End Position ?#xNz=V
int nThreadID; //Thread's ID cI4%zeR
boolean bDownOver = false; //Downing is over _=jc%@]1y
boolean bStop = false; //Stop identical hi>Ii2T
FileAccessI fileAccessI = null; //File Access interface . ({aPtSt!
l^ni"X
|EaGKC(
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException `LnLd;Z
{ lph3"a^
this.sURL = sURL; !%NxSJ
this.nStartPos = nStart; PGMu6$
this.nEndPos = nEnd; C8cB Lsa[J
nThreadID = id; 7Nc@7_=
fileAccessI = new FileAccessI(sName,nStartPos);//定位 x{u_kepv[k
} ?L#C'Lz2+
cD8.rRyD
Q{!lLka
public void run() %}P^B^O
{ MQ2gzKw>
while(nStartPos < nEndPos && !bStop) {o7ibw=E)
{ h[3N/yP
c6s*u%+},
z.eqOPW
try{ +DM+@F
URL url = new URL(sURL); B_M)<Ad
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); .G1NY1\
httpConnection.setRequestProperty("User-Agent","NetFox"); $Vbgfp~U-
String sProperty = "bytes="+nStartPos+"-"; ?]f+)tCMs
httpConnection.setRequestProperty("RANGE",sProperty); (o{-1Dg)
Utility.log(sProperty); JGSeu =)
}nYm^Yh
SY["(vP%#
InputStream input = httpConnection.getInputStream(); kmM_Af&
//logResponseHead(httpConnection); +H_Jr'/
6}IOUWLB@
8iD_md_[
byte[] b = new byte[1024]; pq*b"Jku1
int nRead; fu9y3`
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) jDcE_55o
{ ;=hl!CB
nStartPos += fileAccessI.write(b,0,nRead); b]~X U
//if(nThreadID == 1) 7*OO k"9
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); >DQl&:-)t
} 7'j?GzaQ+
8 +xLi4Pw
4XQv
Utility.log("Thread " + nThreadID + " is over!"); iBxCk^
bDownOver = true; B+ GPTQSTb
//nPos = fileAccessI.write (b,0,nRead); IoJkM-^H&)
} 'Y6{89y
catch(Exception e){e.printStackTrace ();} Kom$i<O?48
} TF|GGYi
} 5|xFY/%
G-Z_pGer^
1QE-[|
//打印回应的头信息 >9F,=63A
public void logResponseHead(HttpURLConnection con) DyG3|5s1R
{ 8;p6~&).C~
for(int i=1;;i++) uwQ{y>SG
{ !li Q;R&
String header=con.getHeaderFieldKey(i); :^3MN
if(header!=null) 5h+g^{BE
//responseHeaders.put(header,httpConnection.getHeaderField(header)); M\,0<{
Utility.log(header+" : "+con.getHeaderField(header)); 0 '~Jr\4
else 6=90 wu3
break; ]ss0~2
} ;:cU/{W
} ,\[&%ph
4eYj.=I
R8Lp8!F'
public void splitterStop() iYHD:cg)~
{ =bZ>>-<
bStop = true; `f*?|)
} 2y#4rl1Utx
C#p$YQf
N+b"LZc
} :doP66["!
sBu=@8R]y
mR[J Xh9s
/* ?nB).fc
**FileAccess.java f_9%kEXICt
*//文件访问(定位，写) !s?vj <
package NetFox; '7 6}6G%
import java.io.*; nBaY|
q*@7A6:FV>
c3P
public class FileAccessI implements Serializable{ -#Yg B5
9O?.0L
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Bb]pUb
RandomAccessFile oSavedFile; ):+n!P
long nPos; d vkA-9
QT9(s\u
WHvN6
public FileAccessI() throws IOException ]$4k+)6
{ %K;,qS'N_
this("",0); n+rAbn5o$
} g*b%
%$Wt"~WE"O
Y@TZReb
public FileAccessI(String sName,long nPos) throws IOException +0.$w
{ bh6Mh<+
oSavedFile = new RandomAccessFile(sName,"rw"); _V1O =iu-
this.nPos = nPos; b@Ik c<
oSavedFile.seek(nPos); -mO[;lO
} iwJBhu0@#
E%3WJ%A
HpSgGhL'J&
public synchronized int write(byte[] b,int nStart,int nLen) ]b.@i&M
{ #|GP]`YT
int n = -1; W.-[ceM
try{ X"y rA;,o
oSavedFile.write(b,nStart,nLen); ,@khV
n = nLen; ]3NH[&+
} "|]'\4UdzQ
catch(IOException e) (JocnM|U
{ VDx=Tsu-
e.printStackTrace (); nDkyo>t.
} %QVX1\>]
-G(z!ed
+su>0'a
return n; giyKEnP
} T#|Qexz6 @
1G=1FGvP
^%)'wDK
} 6QLWF@
?<#6=
rfkk3oy
/* dum! AO
**SiteInfoBean.java YCj"^RC^
*/ ?2 u_E "
package NetFox; *"P :ySA
Cl6y:21]K
1[[` ^v
public class SiteInfoBean { !Jh-v
G>M# BuU
f:B+R
private String sSiteURL; //Site's URL .*r?zDV
private String sFilePath; //Saved File's Path F6}Pwz[c
private String sFileName; //Saved File's Name DFwkd/3"
private int nSplitter; //Count of Splited Downloading File F8Rd#^9PD
)V!9&
X'TQtI
public SiteInfoBean() O9r3^y\>I
{//nSplitter的缺省值为5 [j?n}D@L
//default value of nSplitter is 5 U!XC-RA3 _
this("","","",5); ]chcRc[!
} fS>W-
W7WHH \L/O
oR[,?qu@f
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ipQJn_:2
{ wlAlIvIT
sSiteURL= sURL; 8%_XJyg
sFilePath = sPath; [kt!\-
sFileName = sName; 9Y&n$svB
this.nSplitter = nSpiltter; 0F1 a
drBWo|/
`a["`N^
} hWJ\dwF
z. VuY3
YKJk)%;+w
public String getSSiteURL() d}EGI
{ z;zyk
return sSiteURL; sw[1T_S>
} L oe!@c
o*_[3{FU
^W eE%"
public void setSSiteURL(String value) eZ[CqUJ&
{ ^cZF#%k
sSiteURL = value; 6Hi3h{
} jJQ6]ucwa
"6['!rq0
_'ltz!~
public String getSFilePath() pZ/x,b#.
{ 7 }4T)k(a
return sFilePath; C;0H _
} 4rO07)~l
>DBaKLu\
]ctUl#j
public void setSFilePath(String value) @N7X(@O
{ Tsxl4ZK
sFilePath = value; S`8 h]vX
} |P$tLOrG
lE78Yl]
UA!-YTh
public String getSFileName() .5p"o-:D
{ B# |w}hj
return sFileName; $ii/Q:w T"
} gGxgU$`#c
i;s&;_0{
MRxzOs
public void setSFileName(String value) Y/2@PzA|
{ +XLy Pj
sFileName = value; w,SOvbAxX2
} `{c %d
=5l7{i*`
EoD;'+d
public int getNSplitter() #~^#%G
{ y#F( xm+L
return nSplitter; cgNK67"(
} v(W$\XH
JfxD-9U^>u
Jt\?,~,
public void setNSplitter(int nCount) &p8b4y_
{ -M2c8P:.b
nSplitter = nCount; <.HX_z3l
} %"r3{Hs
} (TM1(<j
)o`|t
&|'1.^f@;E
/* 2.{:PM4Z4
**Utility.java |Gx-c ,{{
*/ OCnQSkj
package NetFox; a x4V(
\L>3E#R-Q
RZ#b)l
public class Utility { 5<wIJ5t
L9M0vkgri
;{[&&qMwU
public Utility() wHq*)7#h#
{ >B<jR$`6@
W&#Ps6)8
5MfbO3
} 5,cq-`
y!&6"l$K]
//线程睡眠 .aV#W@iyK
public static void sleep(int nSecond) Eyv%"+>
{ u|&"l
try{ as=Z_a:0N
Thread.sleep(nSecond); ghq[oK
} N_(qMW
catch(Exception e) Au<NUc 2
{ V*5 ~A[r
e.printStackTrace (); X:+lD58
} Tf(-Duxz
} R".~{6
Yj)H!Cp.xD
//日志 0}}b\!]9
public static void log(String sMsg) `n7*6l<k~4
{ Z`y%#B6x.
System.err.println(sMsg); LfOXgn\
} B*!{LjXV
o9&1Ct
hC2@Gq
public static void log(int sMsg) ! eXDN
{ LlOUK2tZ
System.err.println(sMsg); M6l S2
} !E"&#>r
} Y` t-Bg!~
Teh _
-XBD WV
/* =$xxkc.~G
**TestMethod.java @'>h P
*/ ^h #0e:7<
package NetFox; 7%DA0.g
"I+71Ce
u}Kc>/AF
public class TestMethod { #~QkS_
xc{$=>'G
m%au* 0p
public TestMethod() "=8= G
{ ///xx/weblogic60b2_win.exe 50h?#u6?
try{ F7[ 55RcP
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 6+`+$s0
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); _=l8e-6r
SiteFileFetch fileFetch = new SiteFileFetch(bean); FbO\#p s
fileFetch.start(); h[HFZv~{
} ?=$=c8xw
catch(Exception e){e.printStackTrace ();} (jhDO7
j0P+<@y
Q#!|h:K
} T6_LiB@
_UU-
[C_Dv-d
public static void main(String[] args) y/{&mo1\
{ <uq#smY
new TestMethod(); :+u K1N
} %*J'!PC9n
} a2Q_K2t
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