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)); O$&mFL[`
} =WyZX 7@R
for(int i=0;i<nEndPos.length-1;i++) > dI LF
{ #t:S.A@
nEndPos = nStartPos[i+1]; +'I+o5*
} <b`E_
nEndPos[nEndPos.length-1] = nFileLength; M42Ssn)
} iS WU'K
} =/y]d<g
ifUGY[L
$o0iLFIX/
//启动子线程 4W#vP
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; <SgM@0m
for(int i=0;i<nStartPos.length;i++) Vzdh8)Mu\
{ qln3 k`
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), >0ph9$
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Lvq>v0|
nStartPos,nEndPos,i); \{Z;:,S
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); E_])E`BJ
fileSplitterFetch.start(); %,6#2X nX%
} UEM(@zD]
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), rV R1wsaL
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); :Q $K<)[
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", sk,ox~0R
nEndPos = " + nFileLength); wsIW |@
// fileSplitterFetch[nPos.length-1].start(); s:/8[(A
b[t>te
P@$/P99
//等待子线程结束 \?0&0;5
//int count = 0; ypKUkH/
//是否结束while循环 @z4*.S&tz
boolean breakWhile = false; F)&@P-9+
5iz{op<$,
ysxb?6
while(!bStop) trPAYa}W
{ i'H/ZwU
write_nPos(); 4C<jdv_J
Utility.sleep(500); \Xm,OE_v"
breakWhile = true; M=FxB;v
!;i`PPRwk
lef2X1w}!
for(int i=0;i<nStartPos.length;i++) @kpv{`Y
{ Bg5Wba%NK
if(!fileSplitterFetch.bDownOver) F(k.,0Nc
{ t2F_uCr
breakWhile = false; v0-cd
break; }.3nthgz
} a`&f
} <49K>S9O
if(breakWhile) QMa;Gy
break; R:e<W/P"
hd>aZ"nm1
_/uFsYC
//count++; K/tRe/t}
//if(count>4) 6-yd]("
// siteStop(); "U!AlZ`g
} rai3<_W<
=yr0bGy`-
y4*U6+#.
System.err.println("文件下载结束！"); A'q#I>j`
} TD1 [
catch(Exception e){e.printStackTrace ();} i5Zk_-\#H
} C~nzH,5
^B(V4-|
Bt>}rYz1
//获得文件长度 LJk@Vy <?
public long getFileSize() S4^vpY DeN
{ mL{B!Q
int nFileLength = -1; <(-= 'QA
try{ $FlW1E j
URL url = new URL(siteInfoBean.getSSiteURL()); 'oF%,4 !Y
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); As3.Q(#Z
httpConnection.setRequestProperty("User-Agent","NetFox"); l)Pu2!Ic
1<BX]-/tP
&<wuJ%'>)Z
int responseCode=httpConnection.getResponseCode(); QW$G
if(responseCode>=400) oFy=-p+C
{ `tHvD=`m.
processErrorCode(responseCode); i`QKH
return -2; //-2 represent access is error |zQ4u
} P;P%n
g .onTFwN
lJu;O/
String sHeader; J?RabYd ~
eoai(&o0$
W=#:.Xj[
for(int i=1;;i++) !n* +(lZ
{ 9Wnn'T@Tl
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); +?u~APjNN
//Utility.log(in.readLine()); q#vQv5
sHeader=httpConnection.getHeaderFieldKey(i); ]bj&bk#
if(sHeader!=null) .q `Hjmg<
{ Xe<sJ.&Wf
if(sHeader.equals("Content-Length")) ]$Yvj!K*Q
{ Fs{x(_LOr
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); q;<h[b?
break; _CW(PsfY
} :uWw8`
} v}1QH
else ]8Q4BW
break; k 8UO9r[
} 1u: gFUb
} 6^]!gR#B
catch(IOException e){e.printStackTrace ();} E"+QJ~!
catch(Exception e){e.printStackTrace ();} Svondc 4
RRRCS]y7$t
4*Q#0`um
Utility.log(nFileLength); ^.1c{0Y^0
7on.4/;M
?Cl%{2omO
return nFileLength; |K.mP4CKY
} Qa.<K{m#?
EQf[,
(iL|Sq&}b
//保存下载信息（文件指针位置） [x9KVd ^d
private void write_nPos() 1+9W+$=h2
{ POvP]G9'"
try{ Z8rvWH9
output = new DataOutputStream(new FileOutputStream(tmpFile)); clNkph
output.writeInt(nStartPos.length); R{ a"Y$
for(int i=0;i<nStartPos.length;i++) Q^ pmQ
{ B[V+ND'(
// output.writeLong(nPos); U<CTubF
output.writeLong(fileSplitterFetch.nStartPos); p1&b!*o-&
output.writeLong(fileSplitterFetch.nEndPos); 7g%E`3)"
} Z?%zgqTXb
output.close(); `&D|>tiz
} GM3f-\/
catch(IOException e){e.printStackTrace ();} cm?\ -[cV
catch(Exception e){e.printStackTrace ();} ~ ip,Nl
} S-k8jm
#a<Gxj
VH+%a<v"
//读取保存的下载信息（文件指针位置） bsB*533
private void read_nPos() :/Q
{ \~fONBY
try{ rcMwFE?|xq
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); +n#V[~~8AI
int nCount = input.readInt(); $e*ce94
nStartPos = new long[nCount]; m|{3),#V
nEndPos = new long[nCount]; ~C>?W[Y
for(int i=0;i<nStartPos.length;i++) TNGU6j}oq
{ BsEF'h'Owh
nStartPos = input.readLong(); hS)'a^FV
nEndPos = input.readLong(); huJ&]"C
} jg.QRny^
input.close(); Y8o)FVcyNy
} KU8Jbl*
catch(IOException e){e.printStackTrace ();} E=>FjCsu<-
catch(Exception e){e.printStackTrace ();} .ox8*OO<
} %d?cP}V
.7l&1C)i
*g6n
private void processErrorCode(int nErrorCode) qWODs
{ Z@3i$8
System.err.println("Error Code : " + nErrorCode); ynE)Xdh
} kP-3"ACG
7PtN?;rP
;\=M;Zt
//停止文件下载 [N/"5 [
public void siteStop() h&--,A >
{ /(iFcMT
bStop = true; =zKhz8B(
for(int i=0;i<nStartPos.length;i++) ApAO/q
fileSplitterFetch.splitterStop(); :E:38q,hG
8$0rR55
fp+gyTnd3
} H[S%J3JI
} n p\TlUc
//负责部分文件的抓取 paKSr|O
**FileSplitterFetch.java k} |
*/ %O!v"Xh
package NetFox; %`&2+\`
[uI|DUlI6o
Bh;7C@dq
import java.io.*; @JyK|.b#0
import java.net.*; 9Hf9VC3
fSs4ZXC
Uc@Ao:
public class FileSplitterFetch extends Thread { 4`!Z$kt
{\c(ls{
J2'Nd'
String sURL; //File URL >D(RYI
long nStartPos; //File Snippet Start Position +\F'iAs@
long nEndPos; //File Snippet End Position joiL{
int nThreadID; //Thread's ID 2oNk93D
boolean bDownOver = false; //Downing is over (]Y 5eM
boolean bStop = false; //Stop identical rvXWcu-"
FileAccessI fileAccessI = null; //File Access interface K95p>E`9e
">y%iE
cp#JBHO
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException A?-oL='
{ yIDD@j=l
this.sURL = sURL; J6L K
this.nStartPos = nStart; DX"xy
this.nEndPos = nEnd; i`dCG[
nThreadID = id; w*oQ["SL
fileAccessI = new FileAccessI(sName,nStartPos);//定位 aC%m-m
} uF1~FKB
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r=X}%~_8X
public void run() qoj$]
{ S"OR%
while(nStartPos < nEndPos && !bStop) rdJ d#S
{ XT@-$%u
Gu2P\I2zx
&8l%T'gd
try{ d5D$&5Ec
URL url = new URL(sURL); n&-qaoNl
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 3b+d"`Y^S
httpConnection.setRequestProperty("User-Agent","NetFox"); 9Hc$G{[a
String sProperty = "bytes="+nStartPos+"-"; $!8-? ?ML
httpConnection.setRequestProperty("RANGE",sProperty); PDrZY.-
Utility.log(sProperty); =gJb^ Gx(w
,'p2v)p^4
\H=&`?
InputStream input = httpConnection.getInputStream(); !+L/Khw/C
//logResponseHead(httpConnection); ]y,==1To
rld67'KcE
`<\1[HJ\
byte[] b = new byte[1024]; X&0 uI*r
int nRead; @>E2?CV
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 2ioQb`=
{ ~:3QBMk::
nStartPos += fileAccessI.write(b,0,nRead); BPdfYu,il
//if(nThreadID == 1) N1|$$9G+
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); \ aHVs
} U2ZD]q
\9/ b!A
Lz:(6`S
Utility.log("Thread " + nThreadID + " is over!"); BI $
bDownOver = true; IGtl\b=
//nPos = fileAccessI.write (b,0,nRead); .h>8@5/s
} IuNiEtKx
catch(Exception e){e.printStackTrace ();} r9 !Tug*>m
} c2e tc8
} ?zQA
K9OYri^TQ
xv&Q+HD
//打印回应的头信息 qeL5D*
public void logResponseHead(HttpURLConnection con) V\^EfQ
{ .R9IL-3fO
for(int i=1;;i++) [BT/~6ovrZ
{ Qt/8r*Oe
String header=con.getHeaderFieldKey(i); FvJd8kV
if(header!=null) Vv8jEZ8
//responseHeaders.put(header,httpConnection.getHeaderField(header)); V( -mD
Utility.log(header+" : "+con.getHeaderField(header)); *{yK 8
else Up,vD)tG
break; D,g1<:<
} hNd}Y'%V
} lhw()u
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lhw ,J]0*
public void splitterStop() I+dbZBX
{ FKT1fv[H
bStop = true; pGK;1gVj
} N9vP7
yb/%?DNQT
3Ei5pX=g
} 'ul~7h;n
Ygl%eP%Z
I;Bjfv5
/* UGuxV+Nwf
**FileAccess.java x >^Si/t
*//文件访问(定位，写) QCX8IIHG
package NetFox; cdG|m[
import java.io.*; kjtjw1\o
QNxl/y\l0
Xa[?^P
public class FileAccessI implements Serializable{ w);6K[+;
* ;Cy=J+
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 ltD37QZQ
RandomAccessFile oSavedFile; 3l3'bw2
long nPos; YJl("MZ
61jI
[fKUyIY_
public FileAccessI() throws IOException !V,{_(LT
{ {FG|\nPw
this("",0); EoxQ */
} hDp6YV,q
N~NQ6:R[
=?s3iP
public FileAccessI(String sName,long nPos) throws IOException Jte#ZnP
{ vMs$ceq
oSavedFile = new RandomAccessFile(sName,"rw"); '8T=~R6
this.nPos = nPos; E4W zU
oSavedFile.seek(nPos); LbZ:&/t^y8
} w&B#goS
]<q[Do8k
qg}O/K
public synchronized int write(byte[] b,int nStart,int nLen) ?1[\!
{ &_gTD
int n = -1; @;H,gEH^
try{ }LijnHH.
oSavedFile.write(b,nStart,nLen); LI6hEcM=
n = nLen; Wf&W^Q
} BZXUwqEh
catch(IOException e) =T7A]U]
{ yT#{UA^
e.printStackTrace (); 9gEssTkts
} Myq5b`z
o,!T2&}
HCa
return n; wu4NLgkE
} NSFs\a@1
~~6^Sh60g
yGsz2T;w
} B-T/V-c7
_"#!e{N|
n]u<!.X
/* yH<$k^0r*
**SiteInfoBean.java EgDQ+( -
*/ H=\!2XS
package NetFox; )5.C]4jol
L:k9#6
ph#tgLJ
public class SiteInfoBean { `)Z!V?&!
JB&\i#
kee|42E
private String sSiteURL; //Site's URL ?"KC-u|
private String sFilePath; //Saved File's Path w1|A5q'M
private String sFileName; //Saved File's Name f*24)Wn<
private int nSplitter; //Count of Splited Downloading File W(Uu@^
4#'("#R
*k1<: @%e
public SiteInfoBean() W7\&~IWub
{//nSplitter的缺省值为5 Cb_oS4vM
//default value of nSplitter is 5 \AC|?/sH
this("","","",5); brZ sAQ+k
} S#-tOjU*
)|I5j];L
wfP5@!I
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) "sKa`WN}
{ u^j {U}
sSiteURL= sURL; bLnrbid
sFilePath = sPath; c.A|Ir
sFileName = sName; &BvZF
this.nSplitter = nSpiltter; [*Z`Kc
gn{=%`[
@Kgl%[NmX
} 7lo|dg80
QERU5|.wc
7'-j%!#w
public String getSSiteURL() "sgjWo6
{ /LM4-S
return sSiteURL; rO:u6."_
} cf7v[ZZ}
z 8*8OWM
KnNh9^4"\2
public void setSSiteURL(String value) }rdIUlVO\
{ c0Dmq)HK?
sSiteURL = value; }I!hOD>]O
} P N*JR
olW|$?
6ITLGA
public String getSFilePath() *E~VKx1
{ sncIqsZ
return sFilePath; jkF8\dR
} :EtMH(
TbehR:B5g
)!Bd6-
public void setSFilePath(String value) D5an\gE
{ 4"vaMa
sFilePath = value; 2F8|I7R
} ((rv]f{
=]>NDWqpHN
'?Jxt:<
public String getSFileName() P=5NKg
{ =q"eU=9
return sFileName; `PL[lP-<
} dtAbc7
SxjCwX">
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public void setSFileName(String value) do-c1;M
{ CWO=0_>2
sFileName = value; mga6[E<
} 0q9>6?=i
|fHB[ W#
>bUj*#<
public int getNSplitter() - /c7nF
{ 9Z6C8Jv
return nSplitter; dP>w/$C}
} IF@HzT;Q
&l}?v@@+_
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public void setNSplitter(int nCount) GPWr>B.{:S
{ 'ho{eR@d
nSplitter = nCount; g8'DoHJ*
} 7);:ZpDv%L
} `Vq`z]}
+3,|"g::
* \HRw +cL
/* {?{U,&
**Utility.java s~},y]YV
*/ n$2RCQ
package NetFox; \nqo%5XL
&gc`<kLu
)h^NR3N
public class Utility { !CjqL~
\Z/k;=Sla
ZB5?!.ND
public Utility() MF[z-7
{ e(1k0W4B
Q;nAPS
0W>9'Rw
} '9J|=z9.
&HM-g7|C0E
//线程睡眠 Ak~4|w-
public static void sleep(int nSecond) ;TZGC).6
{ `dJDucD
try{ V)D-pV V
Thread.sleep(nSecond); I"xWw/Ec
} ,f: jioY
catch(Exception e) #X.+
{ s>z2 k
e.printStackTrace (); oj}"H>tTp
} eSl-9 ^
} HBLWOQab
4x'AC%&Qi
//日志 U '[?9/T
public static void log(String sMsg) ~_!ts{[E
{ )%du@a8
System.err.println(sMsg); |ia@,*KD
} ykq'g|
.V%*{eHLL
Su8'$CFz$.
public static void log(int sMsg) f|xLKcOP
{ =hw^P%Zn
System.err.println(sMsg); 9u wL{P&
} U |F>W~%
} SZVV40w
b"8FlZ$
8U.$FMx :
/* za,2r^
**TestMethod.java .R5/8VuHF
*/ =8{*@>CX
package NetFox; 8.I9}_
SNvb1&
=LZ>su
public class TestMethod { ]5|z3<K^
Goj4`Hc
j$eCe<.3
public TestMethod() A|<;
{ ///xx/weblogic60b2_win.exe |#TXE|#ux
try{ $cK^23H/Fj
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); eX<K5K.B
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); $ u2Cd4
SiteFileFetch fileFetch = new SiteFileFetch(bean); _1JmjIH)M
fileFetch.start(); PI7IBI
} 6tOi^+qN
catch(Exception e){e.printStackTrace ();} '\*A"8;h
E_[ONm=,
R@r{
} g'G8 3F
3kLOoL?
- s|t^
public static void main(String[] args) ~eo^`4O{{
{ J>v$2?w`w
new TestMethod(); .]Ybp2`"U
} v#=ayWgk
} n0.8)=;2
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