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)); U^%9 )4bj
} K;oV"KRK
for(int i=0;i<nEndPos.length-1;i++) CifA,[l34
{ )@}A r
nEndPos = nStartPos[i+1]; (VgNb&Yo9
} }@Xh xZu
nEndPos[nEndPos.length-1] = nFileLength; tNK^z7Dm
} .#*D!;f
} t]s94 R q
Y!SE;N&
`-VG ?J
//启动子线程 fO K|:
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; h`=r)D
for(int i=0;i<nStartPos.length;i++) A9 U5,mOz
{ \B_i$<Sz
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), N83!C=X'
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), l+%Fl=Q2em
nStartPos,nEndPos,i); 4~!Eje!
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); LU%#mY
fileSplitterFetch.start(); c$9sF@K?
} R7lYu\mA
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), WFouoXlG0
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); :-z&Y492
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", rfYP*QQY
nEndPos = " + nFileLength); G.E[6G3
// fileSplitterFetch[nPos.length-1].start(); 70_}S*T
Y?<)Dg.[
Gb;99mE
//等待子线程结束 z&O#v9.NE|
//int count = 0; \.o=icOx
//是否结束while循环 # Mu<8`T-
boolean breakWhile = false; ^w.]Hd2
7%e1cI
/iplU
while(!bStop) u t$c)_
{ u$C\E<G^
write_nPos(); 42&v% ;R
Utility.sleep(500); a"x}b
breakWhile = true; 8) HBh7/
F% `zs\
_BbvhWN&+
for(int i=0;i<nStartPos.length;i++) ?\ZL#)hr"p
{ k@yh+v5
if(!fileSplitterFetch.bDownOver) =~&VdPZ
{ 6ZcXS
breakWhile = false; *r;xw
break; 3f"C!l]Xu
} + ~"5!
} \/ErPi=g
if(breakWhile) jXixVNw
break; e?b)p5g
5Q W}nRCZ
ZWS2q4/S
//count++; 802H$P^ps
//if(count>4) V C-d0E0
// siteStop(); =>qTNh*'
} A{N\)
eNbpwne
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System.err.println("文件下载结束！"); -jB3L:
} z8E1m"
catch(Exception e){e.printStackTrace ();} ];1R&:t
} &kzj?xK=(j
A (okv
c+g@Z"es
//获得文件长度 `PgdJrE
public long getFileSize() k[%aCGo
{ lNz]HiD
int nFileLength = -1; E$A3|rjnoN
try{ ;'0=T0\
URL url = new URL(siteInfoBean.getSSiteURL()); xR?V,uV'$&
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); vQ1 v#Z
httpConnection.setRequestProperty("User-Agent","NetFox"); zU&L.+
2z\e\I
MG{l~|\x)
int responseCode=httpConnection.getResponseCode(); I-DXb M
if(responseCode>=400) 8PBvV[
{ Z+4D.bA
processErrorCode(responseCode); T7[NcZ:I
return -2; //-2 represent access is error WF[bO7:
} F'FP0t!S
T]9m:zX9s
((bTwx
String sHeader; O$D?A2eI
;SY\U7B\
aJzLrX
for(int i=1;;i++) cE\>f8 I
{ !Ms[eB
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); yCP4r6X0
//Utility.log(in.readLine()); /TV=$gB`
sHeader=httpConnection.getHeaderFieldKey(i); Dvc&RG
if(sHeader!=null) e2cP *J
{ 6;iJ*2f5V
if(sHeader.equals("Content-Length")) `XKVr
{ x#*QfE/E(@
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); iOCqE 5d3
break; l63hLz
} BUsV|e\
} %\Wf^6Y^
else \)/yC74r7(
break; R[jEvyD>(
} &%mXYj3y5
} !RH.|}
catch(IOException e){e.printStackTrace ();} /.1.MssQM
catch(Exception e){e.printStackTrace ();} yK%ebq]
@7<uMasfp
(Un_!)
Utility.log(nFileLength); ,r8Tbk]m
\r{W
_S`o1^Ad
return nFileLength; S1S;F9F
} 'hqBo|
Qk976
eOI (6U!
//保存下载信息（文件指针位置） qfoD
private void write_nPos() Qk1xUE
{ ~*W!mlg
try{ <RNJ>>0
output = new DataOutputStream(new FileOutputStream(tmpFile)); Zd:Taieh@
output.writeInt(nStartPos.length); ,Lr<)p
for(int i=0;i<nStartPos.length;i++) UVQ7L9%?f
{ /JkC+7H4
// output.writeLong(nPos); [U/(<?F{(
output.writeLong(fileSplitterFetch.nStartPos); .iD*>M:W
output.writeLong(fileSplitterFetch.nEndPos); OEx^3z^
} Iw<i@=V
output.close(); Av'GB
} }Gyqq6Aeb
catch(IOException e){e.printStackTrace ();} JM- t<.
catch(Exception e){e.printStackTrace ();} P [Uy
} Y!J>U
r.ZF_^y}+
$(e#aHB
//读取保存的下载信息（文件指针位置） a^d8I
private void read_nPos() :>Rv!x`
{ GVHV =E
try{ 6(d}W2GP
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 9}a_:hAy/
int nCount = input.readInt(); Z[__"^}
nStartPos = new long[nCount]; jO*l3:!~\
nEndPos = new long[nCount]; kHw_ S-
for(int i=0;i<nStartPos.length;i++) R218(8S
{ lKZB?Kk^w\
nStartPos = input.readLong(); YQJ==C1
nEndPos = input.readLong(); U8qtwA9t
} LI2&&Mw
input.close(); JM1R ;i6
} D%6;^^WyUx
catch(IOException e){e.printStackTrace ();} GaX[C<Wt
catch(Exception e){e.printStackTrace ();} g<{xC_J
} )q7UxzE+
m<FOu<y
8#!i[UFdj
private void processErrorCode(int nErrorCode) ;bHV
{ l2N]a9bq@
System.err.println("Error Code : " + nErrorCode); iY"l}.7)
} \%^%wXfp
]BR,M4
U!U$x74D5
//停止文件下载 sBrI}[oyx
public void siteStop() {ZY+L;eg1
{ P) 3mX.(}
bStop = true; U- )i+}Ng
for(int i=0;i<nStartPos.length;i++) [q !TIq
fileSplitterFetch.splitterStop(); ^&y$Wd]6
\]$IDt(s
_uc hU=
} V3 ~~
} .{y uo{u
//负责部分文件的抓取 Reatdh
**FileSplitterFetch.java qOIW(D
*/ da)NK!
package NetFox; @E:,lA
mZd , 9
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import java.io.*; AU2i%Q!
import java.net.*; kbM3
5mb]Q)f9-
EkziAON
public class FileSplitterFetch extends Thread { jH_JmYd
,}K<*t[I
^o7;c[E`
String sURL; //File URL V+O"j^Z_J
long nStartPos; //File Snippet Start Position 6{txm+U
long nEndPos; //File Snippet End Position eq UME
int nThreadID; //Thread's ID VkZ7#
boolean bDownOver = false; //Downing is over 72'5%*1
boolean bStop = false; //Stop identical 9-MUX^?u
FileAccessI fileAccessI = null; //File Access interface 7hsGua
jy'13G/b\
z[Xd%mhjO
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException KZ/=IP=
{ K'GBMnjD
this.sURL = sURL; >y,-v:Vy
this.nStartPos = nStart; ti#7(^j
this.nEndPos = nEnd; 'q`^3&E
nThreadID = id; Cg(Y&Gxf.
fileAccessI = new FileAccessI(sName,nStartPos);//定位 .0es3Rj
} <_7*67{
DY`kx2e!
;3@cy|\:
public void run() (SvWvm
{ {E@Lft-
while(nStartPos < nEndPos && !bStop) A,a.8!*}vd
{ S_Wrw z
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try{ .X;3,D[w
URL url = new URL(sURL); /{&tY:;m
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); bD?VU<)3
httpConnection.setRequestProperty("User-Agent","NetFox"); ml+; Rmvb
String sProperty = "bytes="+nStartPos+"-"; % yw?s0
httpConnection.setRequestProperty("RANGE",sProperty); 76`8=!]R
Utility.log(sProperty); qw^uPs7Uw
ynQ: >tw
7Ve1]) u
InputStream input = httpConnection.getInputStream(); w9bbMx
//logResponseHead(httpConnection); I"A_b}~*}
Eqj_m|@
2%_vXo=I
byte[] b = new byte[1024]; ci?qT,&
int nRead; 3R.W>U
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ~=uWD&5B4
{ _I:/ZF5
nStartPos += fileAccessI.write(b,0,nRead); N/MUwx;P
//if(nThreadID == 1) ]7Tkkw$
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); (KDD e}f
} J1C3&t}
gaZu;t2u
-;^j:L{
Utility.log("Thread " + nThreadID + " is over!"); OCBgR4I
bDownOver = true; JzQ)jdvp
//nPos = fileAccessI.write (b,0,nRead); +%ee8|\
} |#]@Z)xa
catch(Exception e){e.printStackTrace ();} X:vghOt?
} w5Y04J
} 7/I,HxXp!
;V*l.gr'2
v>Q#B
//打印回应的头信息 \1D<!k\S
public void logResponseHead(HttpURLConnection con) 2AT5
{ H|3:6x
for(int i=1;;i++) MygfT[_
{ Cv6'`",Yzm
String header=con.getHeaderFieldKey(i); snobT Q
if(header!=null) X-K=!pET
//responseHeaders.put(header,httpConnection.getHeaderField(header)); *Q?tl\E
Utility.log(header+" : "+con.getHeaderField(header)); VY |_dk
else t*Sa@$p
break; I ?gSG*m
} A%KDiIA
} CDQW !XHc
=8AO:
Lr$go6s
public void splitterStop() dfKF%27
{ gOSJM1Mr3
bStop = true; Enum/O5
} M2OIBH4!
k_ & :24Lj
1w@(5 ^V
} K|zZS%?$
WrQDX3
I>]oS(GNT
/* *>7>g"
**FileAccess.java dCi?SIN
*//文件访问(定位，写) [ 9 {*94M
package NetFox; KL1/^1
import java.io.*; Ql/cN%^j$
TC!Yb_H}gN
l?Udn0F
public class FileAccessI implements Serializable{ {o_X`rgrL
+ga k#M"n\
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 l=S35og
RandomAccessFile oSavedFile; {XR6>]
long nPos; Uc7mOa}4
dP#|$1
UQ)W%Y;[0
public FileAccessI() throws IOException OK[T3/v,
{ "c3Grfoz
this("",0); K28+]qy[
} dgR g>)V
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wvO|UP H\
public FileAccessI(String sName,long nPos) throws IOException /oR0+sH]
{ hn5h\M?
oSavedFile = new RandomAccessFile(sName,"rw"); ~ELNyI11
this.nPos = nPos; sy:[T T!w
oSavedFile.seek(nPos); %<k2#6K
} qkt0**\
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lD)%s!
public synchronized int write(byte[] b,int nStart,int nLen) jF ^~p9z
{ ~zHjMo2
int n = -1; HJLu'KY}
try{ ?I6fye7
oSavedFile.write(b,nStart,nLen); C7rNV0.Fq
n = nLen; 5b*M*e&=C
} K{&mI/;
catch(IOException e) @Z*W
{ Dd'm U
e.printStackTrace (); rM`X?>iT+
} Ov5"
Huy5-[)15
61SlVec*o8
return n; C"6?bg5N
} Ja,wfRq
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sPr~=,F
} &ib5*4!
fKeT,U`W
d;zai]]
/* 1,6}_MA
**SiteInfoBean.java ^Y=\#-Dd
*/ A0o-:n Fu
package NetFox; N*"p|yhd]
{9?JjA
LgKaPg$
public class SiteInfoBean { @OV|]u
kjg~n9#T
q;R],7Re
private String sSiteURL; //Site's URL V}J)\VZ2#
private String sFilePath; //Saved File's Path gbI^2=YT'
private String sFileName; //Saved File's Name WlB
private int nSplitter; //Count of Splited Downloading File iI\oz&!vH
'?!zG{x
Ir {OheJ
public SiteInfoBean() ]^Qn
{//nSplitter的缺省值为5 !j:9`XD|
//default value of nSplitter is 5 $CY~5A`l9
this("","","",5); I/a/)No
} >hPQRd
q|j2MV5#g
V,mw[Hw
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) IEXt:
{ T;L>;E>B
sSiteURL= sURL; ]ro*G"-_1#
sFilePath = sPath; gG]Eeu+z
sFileName = sName; >d,jKlh^.%
this.nSplitter = nSpiltter; wCr(D>iM
!D@ZYK;
b:Wm8pp?
} GO__$%~
N"" BCh"
%5eY'
public String getSSiteURL() q?4p)@#
{ ;LG#.~f
return sSiteURL; nSW=LjrO~<
} )\eI;8
`V`lo,"\
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public void setSSiteURL(String value) X;i~<Tq
{ L\@I*QP
sSiteURL = value; <~6h|F8
} l5zS
eO?p*"p"F
4Uphfzv3D
public String getSFilePath() znxnL,-
{ x[$z({Yf
return sFilePath; G&i!Hs
} g]4(g<:O
qAn!RkA
;\]b T;#
public void setSFilePath(String value) f4Xk,1Is
{ ?AJKBW^
sFilePath = value; PcA2/!a
} )TVFtI=,NN
mS~o?q-n
*v9 2
public String getSFileName() Y~L2
{ }s(N6a&(
return sFileName; yzerOL
} *M:B\D
n/SwP
K_RjX>q%N
public void setSFileName(String value) \6R,Nq
{ 6LalW5I
sFileName = value; \/: {)T~
} 2w["aVr =
$wo?!gt
}T&iewk
public int getNSplitter() NYrQ$N"
{ v6>_ j L
return nSplitter; *=(lyx_O
} gDQ1?N'8{t
f"%{%M$K
U)E(`{p]
public void setNSplitter(int nCount) M luVx'
{ :cF[(i/k4
nSplitter = nCount; ^Wt*
} U<DZ:ds?T
} n ~shK<!C
L&u$t}~)
IIn"=g=9
/* xlA$:M&
**Utility.java Qa-K$dm%
*/ sj HrPs e
package NetFox; I'uSp-Sfy
9s6U}a'c
v^d]~!h
public class Utility { hRUhX[
j$?{\iXZ
Jl#%uU/sx
public Utility() *Zt#U#
{ \$*7 >`k
Rm255zp
y:~ZLTAv
} Hn5|B 3vN
BqD'8zLD
//线程睡眠 P<M?Qd1.
public static void sleep(int nSecond) B9NWW6S
{ {>DEsO
try{ )qo {c1X
Thread.sleep(nSecond); A8uVK5
} 2O.i\cH
catch(Exception e) #xX5,r0
{ }\\KYyjY
e.printStackTrace (); \s=t|Wpu2
} "4riSxEyF
} El.hu%#n*G
_AAaC_q
//日志 VF?<{F
public static void log(String sMsg) vms|x wb
{ xv(9IEjt0
System.err.println(sMsg); Jk7|{W\OA
} 5,_u/5Y4
m1B+31'>^
d1AioQ9
public static void log(int sMsg) YwDbPX
{ r'^Hg/Jzt
System.err.println(sMsg); *AO,^R&e.
} X*/ho
} gQ'zW
$8UUzk
Cs9.&Y
/* V@zg}C|e
**TestMethod.java ^(vs.U^U<
*/ ([SU:F!uW(
package NetFox; n>ULRgiT:o
t&H?\)!4
r^FhTzA=1
public class TestMethod { . $BUw
+S>j0m<*
}4 )H
public TestMethod() F5P[dp-`1
{ ///xx/weblogic60b2_win.exe _I@9HC 4
try{ 0AZ")<^~7
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); (s.0PO`
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 6:b!F
SiteFileFetch fileFetch = new SiteFileFetch(bean); W>) M5t4i
fileFetch.start(); &"yx<&c}
} yv t.
catch(Exception e){e.printStackTrace ();} $"+djI?E9
}Yb[
Zq+v6fk_Mn
} ^q{9
X <f8,n
cG[l!Z
public static void main(String[] args) 0)Uce=t`
{ (SpX w,:
new TestMethod(); - Ajo9H
} ] eotc2?u
} jyZ (RB
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