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)); Nf+b"&Zh`
} oRN-xng
for(int i=0;i<nEndPos.length-1;i++) @=w<B4L
{ Bhqft;Nuh
nEndPos = nStartPos[i+1]; *KK+X07
} NT%W;)6m9
nEndPos[nEndPos.length-1] = nFileLength; y#Ht{)C
} EG'[`<*h
} 8,?v?uE
"Th$#3
v]2S`ffP
//启动子线程 _2fkb=2@
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; bLz*A-
for(int i=0;i<nStartPos.length;i++) qZ@0]"h
{ @vgG1w
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), !.7udYmB
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 5q{h 2).)
nStartPos,nEndPos,i); u{&B^s)k.
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); AJt!!crs
fileSplitterFetch.start(); nU+tM~C%a
} 4!$ M q;U
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), (VyNvB
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); J MX6yV
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", B;Nl~Y|\
nEndPos = " + nFileLength); "_L?2ta
// fileSplitterFetch[nPos.length-1].start(); W]<$0
"Z,q?Fc
hf!|\f
//等待子线程结束 R~L0{` 0
//int count = 0; L;_c|\%
//是否结束while循环 {s,+^7
boolean breakWhile = false; KHKS$D
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P`$12<\O1
while(!bStop) oC*ees g_
{ z `8cOK-
write_nPos(); >: 0tA{bV
Utility.sleep(500); P#kGX(G9!
breakWhile = true; W:&R~R
~CRSL1?
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for(int i=0;i<nStartPos.length;i++) >(9F
{ <Pqv;WI|R
if(!fileSplitterFetch.bDownOver) E ?2O(
{ @b&84Gn2 r
breakWhile = false; ,reJ(s
break; ]7sx;KFv
} B,$l4m4
} \v@({nB8
if(breakWhile) PsjbR
break; O[~x_xeW
4YG/`P
/%x7+Rl\-^
//count++; ~yJ4qp-
//if(count>4) *ck}|RhR
// siteStop(); .;/L2Jv
} &!.HuRiuC
<T,A&`/
vvu<:16
System.err.println("文件下载结束！"); 8"'x)y
} -Q e~)7
catch(Exception e){e.printStackTrace ();} O0l^*nZ46t
} W+>wu%[L
aA*9,
O>r-]0DI[
//获得文件长度 sOFa!bdPW
public long getFileSize() Os),;W0w4
{ n"{X!(RIcx
int nFileLength = -1; dT@UK^\
try{ QezSJ io
URL url = new URL(siteInfoBean.getSSiteURL()); u4'z$>B
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 3*S[eqMJc
httpConnection.setRequestProperty("User-Agent","NetFox"); R|,7d:k
C?m,ta3
tn<6:@T
int responseCode=httpConnection.getResponseCode(); _j#SpL'P
if(responseCode>=400) B+VuUt{S
{ w8M2N]&:
processErrorCode(responseCode); NGzgLSm\
return -2; //-2 represent access is error e$l6gY
} Rq)BssdF
a<Uqyilm
DQ6jT@ZDH
String sHeader; 'w<BJTQIL
gp
)q^ Bj$
for(int i=1;;i++) ] pPz@@xx
{ crmUrF#
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); tB6k|cPC
//Utility.log(in.readLine()); # mT]j""
sHeader=httpConnection.getHeaderFieldKey(i); mBl7{w;Iv
if(sHeader!=null) /A(NuB<Pq
{ B4W\ t{
if(sHeader.equals("Content-Length")) |HbEk[?^s
{ (!zM\sF
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); :$H!@n*/R
break; Ti= 3y497S
} w=J4zkWk
} F,}s$v
else tHI*,
break; p5*lEz|$
} ,b'4CF
} TbNGgjT
catch(IOException e){e.printStackTrace ();} K3ukYR
catch(Exception e){e.printStackTrace ();} P^IY: -s
:,F=w0O
MW@DXbKVl
Utility.log(nFileLength); Q=+8/b
-<oZ)OfU
DP>mNE
return nFileLength; YFx=b!/s
} .hN3`>*V
epVH.u%
zqGYOm$r
//保存下载信息（文件指针位置） k>{-[X,/OV
private void write_nPos() 8XbR
{ 79tJV
try{ `Cj,HI_/*
output = new DataOutputStream(new FileOutputStream(tmpFile)); t<lyg0f
output.writeInt(nStartPos.length); O,9X8$5H-a
for(int i=0;i<nStartPos.length;i++) N1? iiv
{ v MWC(m
// output.writeLong(nPos); kPJ~X0Fr{t
output.writeLong(fileSplitterFetch.nStartPos); :&$Xe1)i]
output.writeLong(fileSplitterFetch.nEndPos); cdsQ3o
} nHU3%%%cU
output.close(); >sV Bj(f
} 8|<f8Z65!
catch(IOException e){e.printStackTrace ();} Mcb<[~m
catch(Exception e){e.printStackTrace ();} )/TVJAJ
} wea\8[U3"
6QptKXu7
t^$Div_%G
//读取保存的下载信息（文件指针位置） ^K>pT}u
private void read_nPos() m?vAyi
{ D[W}[r
try{ 2o}8W7y
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); SD I,M
int nCount = input.readInt(); nK:`e9ES
nStartPos = new long[nCount]; 9oD#t~+F4
nEndPos = new long[nCount]; I)uASfT$
for(int i=0;i<nStartPos.length;i++) ~p!QSRu~,b
{ "j;!_v>=f`
nStartPos = input.readLong(); e)og4
nEndPos = input.readLong(); @f'AWeJ2
} Q,TaJ]
input.close(); WFks|D:sB
} +{bh
catch(IOException e){e.printStackTrace ();} h!;MBn`8
catch(Exception e){e.printStackTrace ();} 3?6Ber y=
} w5=EtKTi
.Px,=56$X
'.xkn{c
private void processErrorCode(int nErrorCode) (BhL/A 4
{ 'jwTGT5x
System.err.println("Error Code : " + nErrorCode); oPE.gn_$
} s={X-H< 2
:4b- sg#
l9,w>]s
//停止文件下载 m';|}z'
public void siteStop() aGe\.A=
{ <C2c"=b
bStop = true; sd7Y6?_C
for(int i=0;i<nStartPos.length;i++) y& Gw.N}<r
fileSplitterFetch.splitterStop(); U@MOvW)
aw;{<?*
<4SF~i
} F\l!A'Q+t
} +2f> M4q
//负责部分文件的抓取 .jy)>"h0
**FileSplitterFetch.java ^O?l9(=/u
*/ + 4++Z
package NetFox; UeC 81*XZ
AZ]Z,s6
P[r}(@0rJ
import java.io.*; _y.mpX&
import java.net.*; r7IhmdA
Sqb#U{E
@lmke>
public class FileSplitterFetch extends Thread { ,)QmQ^/
9Qkww&VEk
ae^xuM?7
String sURL; //File URL d[S!e`,iD
long nStartPos; //File Snippet Start Position f9&D1Gh+w
long nEndPos; //File Snippet End Position i>rn!?b
int nThreadID; //Thread's ID dIf Jr}ih
boolean bDownOver = false; //Downing is over L@2H>Lh35
boolean bStop = false; //Stop identical s0`uSQ2X
FileAccessI fileAccessI = null; //File Access interface ct]5\g?U'
*3k~%RM%?
w?5b:W,
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException D~%cf
{ d+IPa<N
this.sURL = sURL; .oe,#1Qh{
this.nStartPos = nStart; zO+nEsf^O
this.nEndPos = nEnd; Ny~;"n
nThreadID = id; "7aFVf
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ]c5Shj5|p
} vx ,yz+yP
$@U`zy"Y
.:;i*
public void run() 2GD%=rP2]
{ F(w>lWs;
while(nStartPos < nEndPos && !bStop) 3!}#@<j
{ g=%W"v
I#,,h4C
V]<dh|x
try{ wHY;Y-(ZT
URL url = new URL(sURL); Xr~r`bR=
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); # I<G:)
httpConnection.setRequestProperty("User-Agent","NetFox"); w"sRK
String sProperty = "bytes="+nStartPos+"-"; hyBSS,I
httpConnection.setRequestProperty("RANGE",sProperty); :*8@MjZ4
Utility.log(sProperty); <8y8^m`P9
C qxP@
xA-G&oC]<T
InputStream input = httpConnection.getInputStream(); I{2e0
//logResponseHead(httpConnection); lz>5bR'
VJNPs6
QvqBT
byte[] b = new byte[1024]; #._!.P
int nRead; H`".L^
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Zc"]Cv(
{ 8"4`W~ 3
nStartPos += fileAccessI.write(b,0,nRead); d82IEhZ#
//if(nThreadID == 1) R<wb8iir
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ;;U2I5 M7
} aE;!mod
\/,SH?>4x
Qr0GxGWU
Utility.log("Thread " + nThreadID + " is over!"); ~\Ynih
bDownOver = true; |M0TG
//nPos = fileAccessI.write (b,0,nRead); ~svu0[Vx
} Pq`4Y K
catch(Exception e){e.printStackTrace ();} L@+j8[3BX
} GY4yZa
} Ig6s'^
2/bck)p=
5H',Bm4-
//打印回应的头信息 WUxr@0
public void logResponseHead(HttpURLConnection con) > Euput\
{ =N3~2=g~A
for(int i=1;;i++) '-*r&:
{ Llzowlfe
String header=con.getHeaderFieldKey(i); 'fgDe
if(header!=null) f.u{;W
//responseHeaders.put(header,httpConnection.getHeaderField(header)); "=RB #
Utility.log(header+" : "+con.getHeaderField(header)); 0xjV*0?s
else 6Z'zB&hM}
break; w%$n)7<*
} Dp'/uCW)
} H;Bj\-Pa
X`vDhfh>N
7>4t{aRf_8
public void splitterStop() !YoKKG~_0
{ pu^1s#g8w
bStop = true; J5\> 8I,a
} g-]td8}#
4$;fj1!Z:
5<S1,u5
} n|F`6.G
PJ_|=bn
.p5*&i7
/* ^8\pJg_0
**FileAccess.java >B9rr0d0
*//文件访问(定位，写) o]FQ)WRB
package NetFox; mHhm~u
import java.io.*; *r_.o;6
44]ae~@a
$~2Ao[
public class FileAccessI implements Serializable{ *[jaI-~S
'R$~U?i8
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Hnaq+ _]
RandomAccessFile oSavedFile; Z86[sQBg
long nPos; ]F_u
Wl,yznT
E^qKkl
public FileAccessI() throws IOException *7Mrng
{ c=K M[s.
this("",0); Zw3|HV(so
} EUNG&U
c]O4l2nCL
fpqKa r
public FileAccessI(String sName,long nPos) throws IOException iGp@P=;m
{ \gzNMI*
oSavedFile = new RandomAccessFile(sName,"rw"); -8TLnl~[
this.nPos = nPos; <k)rfv7
oSavedFile.seek(nPos); C2VZE~U+
} MdPwuXI
t EN%mK
6tJM*{$$H
public synchronized int write(byte[] b,int nStart,int nLen) )h/fr|
{ =EG[_i{r
int n = -1; [g/g(RL
try{ @Wv*`
oSavedFile.write(b,nStart,nLen); %>s y`c
n = nLen; :jhJpm1Xq
} 7<) .luV
catch(IOException e) xOt|j4
{ ?$gEX@5h
e.printStackTrace (); mbd@4u
} Lkb?,j5
;+5eE`]a/L
Kg%_e9nj#
return n; YlYTH_L>E
} 1M+mH#?
Aw5yvQ>]e
:JOF!Q
} S |B7HS5
tIRw"sz
'91Ak,cWB
/* Bkcs4 x
**SiteInfoBean.java Vdjca:`
*/ vm Hf$rq
package NetFox; jbG #__#_
FkRrW^?5G
0R; ;ou
public class SiteInfoBean { ~UL;O\-b0
;Neld #%J
No h*1u*
private String sSiteURL; //Site's URL khyVuWN
private String sFilePath; //Saved File's Path "d{ |_Cf
private String sFileName; //Saved File's Name WyO10yvR
private int nSplitter; //Count of Splited Downloading File :V >Z|?[*H
Xp%JPI {
`i<U;?=0'
public SiteInfoBean() _RAPXU~ 6-
{//nSplitter的缺省值为5 zHyM@*Gf(
//default value of nSplitter is 5 %SIbpk%
this("","","",5); pvcD 61,
} _57i[U r
XC~|{d
9CxU:;3
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) X\uN:;?#W{
{ sN;xHTY
sSiteURL= sURL; hg |DpP
sFilePath = sPath; \]GBd~i<
sFileName = sName; GsxrqIaD
this.nSplitter = nSpiltter; f7\$rx
%[5hTf
Ij4oH
} r 5:DIA!
PjDYdT[
|&3[YZY
public String getSSiteURL() L_Ff*
{ +Y6=;*j$
return sSiteURL; 3u_[=a
} 6gNsh
yd'>Mw
7$Jb"s
public void setSSiteURL(String value) A+_361KH
{ Nxp7/Nn3
sSiteURL = value; n~@;[=o?5
} H)ud?vB6
( hp 52Vse
V+(1U|@~
public String getSFilePath() %`?IY<
{ JgEPzHgx
return sFilePath; % tTL
} il|e5TD^
-c{O!z6sX
OWx-I\:
public void setSFilePath(String value) &s-iie$"@x
{ yb\T<*
sFilePath = value; Y23- Im
} F0(P2j
m&a.i B
P%2aOsD0
public String getSFileName() #ueWU
{ \,&,Q
return sFileName; 6V-u<FJ
} E^qJ5pr_P
y(^t&tgjS
Y7vUdCj
public void setSFileName(String value) |Tv}leJF
{ tpPP5C{
sFileName = value; Vq-W|<7C=
} 2@~.FBby7@
+-2o b90_m
S#Q0aGj
public int getNSplitter() 71b0MHNkvv
{ 08czP-)OZ
return nSplitter; ~?#>QN\\c
} nQ*9E|Vx
C-h9_<AwJQ
hQ7-m.UZw
public void setNSplitter(int nCount) yzyBr1s
{ 3']a1\sy^
nSplitter = nCount; yxk:5L \A
} X<8?>#
} {#`O'F>
C GN=kQ
)_C+\K*
/* }_mVXjF
**Utility.java PaD6||1F
*/ b!p]\B!
package NetFox; S4 j5-
&u+l`F^Z
ES}V\k*}
public class Utility { C]EkVcKFA
yE&WGpT
- f?8O6e
public Utility() 0 i'bo*
{ ]SC|%B_*
I=[Ir8};
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} ='vD4}"j
J8'1 ~$6
//线程睡眠 `- HI)-A97
public static void sleep(int nSecond) x{O) n
{ 9r.h^
try{ _`I}"`2H
Thread.sleep(nSecond); %}IrZrh
} 5,\-;
catch(Exception e) ))%f"=:wt
{ bey:Qj??
e.printStackTrace (); {^D; ($lm
} wrQ02?
} Q7.jSL6
8NkyT_\
//日志 KpBOmXE
public static void log(String sMsg) XJ!?>)N .
{ " Tk,
System.err.println(sMsg); C$0rl74Wi
} sYhHh$mwA
%[, R Q">v
Mkh/+f4
public static void log(int sMsg) s~QIs
{ l 88n*O
System.err.println(sMsg); bY-koJo
} D<hX%VJ%M
} >V?W_oM)
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Im?/#tX
/* GEvx<:
**TestMethod.java [+d~He
*/ sib/~j
package NetFox; b<!' WpY-
tPa(H;
]x).C[^
public class TestMethod { b*W,8HF4,
a~ RY 8s
u -)ED
public TestMethod() _Ss}dU9
{ ///xx/weblogic60b2_win.exe "n{';Q)
try{ qzNXz_#+u
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ]cv/dY#
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 9B![l=Gh
SiteFileFetch fileFetch = new SiteFileFetch(bean); e_-7,5Co
fileFetch.start(); 5t-d+vB
} eIy:5/s
catch(Exception e){e.printStackTrace ();} ePZAi"k
[ #ih o(/
Z t4q= Lr
} Ie K+
AFM+`{Cq
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public static void main(String[] args) tAo$;|
{ $0x+b!_l@
new TestMethod(); ~%lA!tsek
} 8KN3|)
} R:(i}g<3
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