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)); R,w54},
} &#oZ>`Qu
for(int i=0;i<nEndPos.length-1;i++) c^Gwri4
{ inv{dg/2
nEndPos = nStartPos[i+1]; ?*R^?[
} lZA>L, \d
nEndPos[nEndPos.length-1] = nFileLength; mYjiiql~
} txfwLqx
} Q xF8=p
@oqi@&L'C
Xf_tj:eO~
//启动子线程 YNJpQAuSn)
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; _IKP{WNB
for(int i=0;i<nStartPos.length;i++) <,X+`m&
{ ({_:^$E\
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), h,'mN\6t
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), <#p|z`N
nStartPos,nEndPos,i); `^bvj]>l
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 3@F+E\k
fileSplitterFetch.start(); -6~dJTm[t
} >_0 i=.\
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), a,57`Ks+n<
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); p]V-<
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", [mB(GL
nEndPos = " + nFileLength); ,4>WLJDo
// fileSplitterFetch[nPos.length-1].start(); ]k`Fl,"
Vi?~0.Z%
jRdhLs,M9
//等待子线程结束 ngkeJ)M0$
//int count = 0; {c\oOM<7
//是否结束while循环 Zn<(,e
boolean breakWhile = false; emkMR{MY
ySuLt@X
RdvPsv}D
while(!bStop) L=$?q/=-
{ {80oRD2=Q
write_nPos(); \emT:Frb
Utility.sleep(500); c"oQ/x
breakWhile = true; B'P,?`
,.1&Ff)S
LRfFn^FPM
for(int i=0;i<nStartPos.length;i++) <S:,`v&Z
{ u|:UFz^p
if(!fileSplitterFetch.bDownOver) kM6 EZ`mj
{ FRs|!\S=
breakWhile = false; a78;\{&L'
break; kV]%Q3t
} Wb*T
} qHcY 2LV
if(breakWhile) CU} q&6h
break; )%nt61P\W
#lLn='4
O23]!S<;
//count++; h}c6+@w&-
//if(count>4) :&\E\9
// siteStop(); D7n&9Z
} 0t/z"
}]Z,\lA
$6]x,Ct
System.err.println("文件下载结束！"); 7J)Hwl
} &].1[&M]
catch(Exception e){e.printStackTrace ();} ~ 33@H
} e[|p0 ,Q
o@Cn_p^X
-*-zU#2|
//获得文件长度 BGk<NEzH
public long getFileSize() 6A{s%v H
{ h&^/, G
int nFileLength = -1; ?\/dfK:!
try{ o*5e14W(:
URL url = new URL(siteInfoBean.getSSiteURL()); c^q O@%s
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); El8.D3
httpConnection.setRequestProperty("User-Agent","NetFox"); 6nhfI\q3wY
Ltq*Vcl\
J{'zkR?Lr
int responseCode=httpConnection.getResponseCode(); NVM2\fs
if(responseCode>=400) c]/O^/
{ MHzsxF|
processErrorCode(responseCode); e]L3=R;
return -2; //-2 represent access is error [.yx2@W
} 4UX]S\X
e"&9G}.f
;*$8iwBQ_
String sHeader; /%@RO^P
2%No>w}/2
~d<`L[
for(int i=1;;i++) MRY)m@*+6
{ r^Rcjyc1
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ~bm2_/RL
//Utility.log(in.readLine()); 5a/ A_..+I
sHeader=httpConnection.getHeaderFieldKey(i); ;V(}F!U\z
if(sHeader!=null) OuJy$e
{ nr9#3Lb
if(sHeader.equals("Content-Length")) RBp(dKxM$w
{ _xZb;PbFE
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ~.y4 ,-
break; Fq\`1Ee{
} t2%bHIG}
} n<(5B|~y
else Vm%ux>}
break; :|6D@
} A.cZa
} Fl|&eO,e
catch(IOException e){e.printStackTrace ();} $S-;M0G x
catch(Exception e){e.printStackTrace ();} FYE9&{]h
KV&_^xSoh|
L08;z
Utility.log(nFileLength); ^V;lZtZ
w"Y55EURB
|Btx&'m
return nFileLength; \(7#N<-
} $TW+LWb
O5n]4)<
B(T4nH_k
//保存下载信息（文件指针位置） 9(gOk
private void write_nPos() .Im+()b&&
{ */h9"B
try{ Ku\#Wj|YrP
output = new DataOutputStream(new FileOutputStream(tmpFile)); @T=HcUP)
output.writeInt(nStartPos.length); nf@u7*#6
for(int i=0;i<nStartPos.length;i++) 4!RI2?4V
{ 38S&7>0@|q
// output.writeLong(nPos); K OHH74}_
output.writeLong(fileSplitterFetch.nStartPos); iKTU28x
output.writeLong(fileSplitterFetch.nEndPos); \}Kp=8@nE
} @z?.P;f9#
output.close(); /M c"K
} +OP:"Q_#
catch(IOException e){e.printStackTrace ();} (ZR"O8
catch(Exception e){e.printStackTrace ();} $GKm`I"
} `-`iS?
<(lSNGv5N
49kia!FR
//读取保存的下载信息（文件指针位置） *X55:yha
private void read_nPos() 2gI_*fG1
{ vF\zZ<R/
try{ H<Taf%JT
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ee?ZkU#@
int nCount = input.readInt(); HWAqJb [
nStartPos = new long[nCount]; $?Mz[X
nEndPos = new long[nCount]; 90v18k
for(int i=0;i<nStartPos.length;i++) _NW OSt
{ { qx,X.5$
nStartPos = input.readLong(); ,H1~_|)<
nEndPos = input.readLong(); ~7H.<kJt
} uk/+ i`=
input.close(); 6)YNjh.{*
} 2= mD
catch(IOException e){e.printStackTrace ();} wLSYzz
catch(Exception e){e.printStackTrace ();} oU5mrS.7M!
} *<j@+Ch
9\0 K%LL
uQ1;+P:L
private void processErrorCode(int nErrorCode) X'4 Yofs
{ 1"6k5wrIA
System.err.println("Error Code : " + nErrorCode); [63;8l}
} &4FdA|9T
*s4!;2ZhsU
m%\[1|N
//停止文件下载 Z9^$jw]
public void siteStop() ?d)|vX3Uf
{ .NC}TFN|
bStop = true; C(Y6t1
for(int i=0;i<nStartPos.length;i++) Zi)8KO[/0
fileSplitterFetch.splitterStop(); F'*&-l
0GVok$r@
{ "c,P:S]
} "c*|vE
} wQ^a2$Z
//负责部分文件的抓取 #4u; `j"4=
**FileSplitterFetch.java }(''|z#UE
*/ d2C:3-4
package NetFox; .>&fwG
S7Fxb+{6D
z+I-3v
import java.io.*; U:e9Vq'N m
import java.net.*; <`qo*__1
PEl]HI_H
uy{KV"%"^g
public class FileSplitterFetch extends Thread { w(-n1oSo
RGLqn{<V
!W7ekPnK
String sURL; //File URL A-$BB=Ot
long nStartPos; //File Snippet Start Position T5;D0tM/
long nEndPos; //File Snippet End Position MzG.Qh'z
int nThreadID; //Thread's ID t79MBgZ
boolean bDownOver = false; //Downing is over Akf9nT
boolean bStop = false; //Stop identical u<zDZ{jt)
FileAccessI fileAccessI = null; //File Access interface 78-:hk
s qKkTG3
|O?Aj1g[c?
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException o*xEaD
{ Fu/CX4R_|
this.sURL = sURL; 8<xy*=%
this.nStartPos = nStart; /<Et
this.nEndPos = nEnd; jGCW^#GE
nThreadID = id; :u0433z:
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ~^*tIIOX
} JGe;$5|q8
)J0VB't
{cA )jW\'
public void run() OUPpz_y
{ .R,8<4
while(nStartPos < nEndPos && !bStop) 10&A3C(E
{ E \RU[
kC`Rd:5
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try{ TF2KZL#A|
URL url = new URL(sURL); F&az":
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 95LyYg
httpConnection.setRequestProperty("User-Agent","NetFox"); !^?qU;|
String sProperty = "bytes="+nStartPos+"-"; y\,f6=%k
httpConnection.setRequestProperty("RANGE",sProperty); `{o$F ::(
Utility.log(sProperty); E-SG8U;
[0!{_E)<
9.s,:?5e
InputStream input = httpConnection.getInputStream(); esI'"hVJ
//logResponseHead(httpConnection); NzlAC
n[CoS
BIj
byte[] b = new byte[1024]; $r15gfne>
int nRead; :)4*^a/lC
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ]0-<>
{ z_n\5.
nStartPos += fileAccessI.write(b,0,nRead); b#='^W3
//if(nThreadID == 1) 1tGgDbJU
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); [.-a$J[4+F
} gDC2 >nV
Hi8Y6|y$D
%/pc=i|+
Utility.log("Thread " + nThreadID + " is over!"); ArXl=s';s4
bDownOver = true; ^l(^z fsZ
//nPos = fileAccessI.write (b,0,nRead); >lLo4M 3
} r?3Aqi"
catch(Exception e){e.printStackTrace ();} {[^#h|U
} ,g|2NjUAc
} {7X~!e|w
[h-norB((
"+h/-2rA
//打印回应的头信息 Pm?B 9S
public void logResponseHead(HttpURLConnection con) |^Kjz{
{ "% Y u wMY
for(int i=1;;i++) 8xTix1u0
{ lT,+bU
String header=con.getHeaderFieldKey(i); :Ss3ck*=
if(header!=null) rQj~[Y.c
//responseHeaders.put(header,httpConnection.getHeaderField(header)); e U;jP]FA
Utility.log(header+" : "+con.getHeaderField(header)); GY-M.|%
else 6+PGwCS
break; 38Efp$)
} _yVPpA[a
} ~L'nzquF
a.,_4;'UE1
AP w6
public void splitterStop() N`1r;%5
{ v3-?CQb(
bStop = true; .@k*p>K
} *Hunp Y
o^GC=Aca`
zH=hIVc
} KY+]RxX
7zGMkl
GAp!nix6h
/* 7#pZa.B)k
**FileAccess.java t?3BCm$Mi
*//文件访问(定位，写) YoAg
package NetFox; KB+]eI-h
import java.io.*; m&Sp1=*Ejy
QJSr:dP4dG
!01i%W'
public class FileAccessI implements Serializable{ =l,#iYJP8
968^"T#
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 l%<c6;
RandomAccessFile oSavedFile; 5f_7&NxT
long nPos; =]b9X7}
|-61(X.
#LWg"i
public FileAccessI() throws IOException P)1EA;
{ n7DLJ`ho{
this("",0); 2.qpt'p[
} C #aFc01B
f3n~{a,[
Z4@y?fv7s
public FileAccessI(String sName,long nPos) throws IOException o#}mkE87
{ s=U\_koyH
oSavedFile = new RandomAccessFile(sName,"rw"); iZC`z }
this.nPos = nPos; U>A6eWhH
oSavedFile.seek(nPos); 0jTMZ<&zZ
} qTy v.#{y
o?\Gm
4J}3,+
public synchronized int write(byte[] b,int nStart,int nLen) UkfA}b^@v
{ u){S$</
int n = -1; Z= ik{/
try{ mz-N{>k
oSavedFile.write(b,nStart,nLen); PbN3;c3
n = nLen; QgZJ`G--
} (&c,twa~
catch(IOException e) `^e*T'UPl
{ fTgbF{?xh
e.printStackTrace (); {aIZFe}B
} Pz1G<eh#{g
b9#m m
#ovM(Mld
return n; JWWInuH
} y/\ZAtnLo
6sy,A~e
Xi+n`T'i
} TrQm]9@
|D+p$^L
|0]YA
/* 453 }S
**SiteInfoBean.java )Y8qWJU
*/ b"3uD`
package NetFox; R#LGFXUj
^XNw$@&',
UOJ*a1BM
public class SiteInfoBean { !mae^A1
)@,N7Y1h
MYu`c[$jZ
private String sSiteURL; //Site's URL W1`Dx(g
private String sFilePath; //Saved File's Path l.uN$B
private String sFileName; //Saved File's Name SdSgn|S
private int nSplitter; //Count of Splited Downloading File KG-y)qXu
lJlhl7
XD 5n]AL
public SiteInfoBean() X&.:H~xS+
{//nSplitter的缺省值为5 Q!`)e@r
//default value of nSplitter is 5 l-cW;b~
this("","","",5); 0W_mCV
} ",QYDFFeF
3? };
T:6K?$y?
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) \*Ts)EW
{ {x9j_/R
sSiteURL= sURL; F$[)Bd/"
sFilePath = sPath; %6N)G!P
sFileName = sName; a^(2q{*
this.nSplitter = nSpiltter; _TrZ'iL}T
o:H'r7N
6-tiRk~
} WqR7uiCi
1*L^^%w
"~_$T@^k>
public String getSSiteURL() x\6];SXX
{ <o~t$TH
return sSiteURL; 5`{=`
} $.``OxJk%
Shs')Zsbv
C0gfJ~M)
public void setSSiteURL(String value) s:3aRQ%
{ gU~ L@R_D
sSiteURL = value; /q T E
} uL bp.N8
)sRN!~
u2Y N[|V
public String getSFilePath() v: giZxR
{ pa>p%
return sFilePath; :,jPNuOA
} q)NXyy4BT
PL9<*.U"=
33*^($bE&
public void setSFilePath(String value) c$.UE
{ [?A&xqO3
sFilePath = value; :2_0L
} h]<GTWj
"pOqd8>]
P`7ojXy
public String getSFileName() I+*osk
{ fdN45in=>
return sFileName; 1]"D%U=
} ;&RUE
;9}w|!/
uPI v/&HA
public void setSFileName(String value) N!,@}s
{ GU_R6Wt+
sFileName = value; 7^ER?@:W
} %POoyH@D}
R7vO,kZ6Q
Wz9 }glr
public int getNSplitter() A_CK,S*\,&
{ C EAwQH
return nSplitter; @c5TSHSL.
} 5*~G7/hT
aQcJjF5x
'b%S3)}
public void setNSplitter(int nCount) 40mgB4I
{ INi(G-!g
nSplitter = nCount; hv8V=Z'Q
} IRD?.K]*
} 8M!If
06L/i,
&_G^=Nc,H
/* HPT$)NeNc
**Utility.java Eufw1vDa
*/ R{u/r%
package NetFox; um,Zt
:Fu.S1j$
QF Vy2 q
public class Utility { 6_rS!X
SCZtHEl9
p%ek)tT
public Utility() n}}$-xl
{ 8 Zhx&
|]*]k`o<)
E:!?A@Fy
} Z2!O)8
`2()Vf
//线程睡眠 .Xqe]cax%
public static void sleep(int nSecond) AQ7w5}g+V
{ aOIE9wO
try{ \ ?sM
Thread.sleep(nSecond); EA) K"C
} vu Vcv
catch(Exception e) 2= S;<J
{ ^Cs?FF@P
e.printStackTrace (); ezS@LFaA
} H$^IT#
} Rf9;jwU
o-H\vtOjE
//日志 !,WO]Ov
public static void log(String sMsg) Hwiw:lPq`E
{ jJc:%h$|2
System.err.println(sMsg); ^qvN:v$1
} qJN!L))
Pk)>@F<
Ww\M3Q`h
public static void log(int sMsg) fXD9w1
{ apy9B6%PJ+
System.err.println(sMsg); .0 }eg$d
} b%A+k"d
} A~0eJaq+
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Qze.1h
/* ,r_%p<lOFu
**TestMethod.java ?E +[
*/ =2J^ '7
package NetFox; 7F$G.LhMw
J> Z.2
; ,9:1.L
public class TestMethod { [a201I0 -
+V Oczl=
)wqG^yv
public TestMethod() [[FDt[ l4
{ ///xx/weblogic60b2_win.exe P z< \q;
try{ L*(Sh2=_
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); X5_T?
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 2e_m>I
SiteFileFetch fileFetch = new SiteFileFetch(bean); nY M2Vxi0+
fileFetch.start(); -_[ZRf?^
} xwSi.~.
catch(Exception e){e.printStackTrace ();} O n/q&h5
`En>o~L;
(baBi9<P=
} (ay((|)
X:2)C-l?
7ILb&JQ!%{
public static void main(String[] args) JfLoGl;pm
{ X+7@8)1(
new TestMethod(); )i/x%^ca$
} _ci8!PP
} g>*P}r~;^b
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