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)); U3Dy:K[
} 6Es-{u(,
for(int i=0;i<nEndPos.length-1;i++) lc'Jn$O@
{ }LE/{]A
nEndPos = nStartPos[i+1]; 'Y-c*q
} )qxL@w.
nEndPos[nEndPos.length-1] = nFileLength; c8u&ev.U
} jy1*E3vQ
} DLz~$TF^
w.V8-9{
?^6RFbke+
//启动子线程 3XA^{&}
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; &-{4JSII
for(int i=0;i<nStartPos.length;i++) <ZnAPh
{ t<`BaU
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), OgzPX^q/=
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), DG& kY+
nStartPos,nEndPos,i); MqNp*n2
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); i.'f<z$<
fileSplitterFetch.start(); sNNt0q(
} AAs&wYp8Yh
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), SIg=_oa
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); E>7[ti_p5
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", C f<,\Aav
nEndPos = " + nFileLength); T{ojla(
// fileSplitterFetch[nPos.length-1].start(); ]6(NeS+
A\?O5#m:$
;,F}!R
//等待子线程结束 3c ^_IuW-
//int count = 0; bS0LjvY9g
//是否结束while循环 >uI|S
boolean breakWhile = false; Kj}}O2
}F\0Bl&
ap=_odW~p
while(!bStop) rfK%%-
{ ~Ipl'cE
write_nPos(); :,cSEST
Utility.sleep(500); `4$" mO>+
breakWhile = true; 0BBWuNF.
L>xN7N3&m
T}g;kppC
for(int i=0;i<nStartPos.length;i++) _jr%s
{ BG=h1ybz
if(!fileSplitterFetch.bDownOver) ni3^J5XW
{ V-)q&cbW]q
breakWhile = false; iHR?]]RF
break; WSh+5](:
} qf'uXH
} J%%nv5y
if(breakWhile) @(ev``L5g
break; l3.HL> o
2"2b\b}my
=>ignoeI
//count++; NBLOcRSh
//if(count>4) j]kx~
// siteStop(); 2vK{Yw
} i)eub`uMy
}7UE
"y62Wo6m)
System.err.println("文件下载结束！"); SB]|y-su
} (LGx;9S?
catch(Exception e){e.printStackTrace ();} Xd{"+'29
} gx#TRp}-
:xv"m {8+
{E>kFeg
//获得文件长度 3F<My+J
public long getFileSize() rrmr#a
{ a2sN$k
int nFileLength = -1; TTBl5X
try{ e)GFJ3sW_
URL url = new URL(siteInfoBean.getSSiteURL()); nIdvff
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Azu$F5G!n
httpConnection.setRequestProperty("User-Agent","NetFox"); :Oy9`vv
v vOG]2z
Ey 4GyAl
int responseCode=httpConnection.getResponseCode(); D4[t@*m>7
if(responseCode>=400) 8 \%*4L'
{ bluhiiATd
processErrorCode(responseCode); }Vk#w%EJ
return -2; //-2 represent access is error cO_En`F
} 29}(l#S}m
qm8[ ^jO&
\_0nH`
String sHeader; t13wQt
ax,%07hJ
U^:+J-z{
for(int i=1;;i++) CH!Lf,G
{ YY'46
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); qMKXS,s
//Utility.log(in.readLine()); Bv@NE2
sHeader=httpConnection.getHeaderFieldKey(i); 1Hk`i%
if(sHeader!=null) uq{w1O5
{ 11O^)_|c
if(sHeader.equals("Content-Length")) 1iig0l6\m
{ #r>
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); D&:,,Dp
break; <mi*AY
} 6-j><'
} evz{@;.R
else W(Xb]t=19
break; eM{,B
} K-Y;[+#g1o
} @tR:}J*9s
catch(IOException e){e.printStackTrace ();} 0%#ZupN
catch(Exception e){e.printStackTrace ();} ~#pQWa5
5Ta<$t
r3{Cuz
Utility.log(nFileLength); E.zY(#S
Hq ]f$Q6:
.\".}4qQ
return nFileLength; T}M!A|
} =0 mf
Am{Vtl)i
nj]l'~Y0
//保存下载信息（文件指针位置） |W:xbtPNy
private void write_nPos() JPRo<jt=
{ ZvM~]8m
try{ MV'q_{J
output = new DataOutputStream(new FileOutputStream(tmpFile)); h3[^uYe
output.writeInt(nStartPos.length); f#FAi3
for(int i=0;i<nStartPos.length;i++) n&y'Mb PB
{ >kU$bh.(
// output.writeLong(nPos); $oDc
output.writeLong(fileSplitterFetch.nStartPos); ?:H4Xd7
output.writeLong(fileSplitterFetch.nEndPos); e5W 8YNA
} W+k SL{0
output.close(); #R-l2OO^]
} A]c'`Nf
catch(IOException e){e.printStackTrace ();} U["'>&B
catch(Exception e){e.printStackTrace ();} )O;6S$z9Y
} vtk0 j
/m"O.17N
`bY>f_5+
//读取保存的下载信息（文件指针位置） Utd`T+AF*
private void read_nPos() r01Z 0>
{ !Z]#1"A8
try{ lkl+o&D9
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); td@I ;d2
int nCount = input.readInt(); 3k3-Ts
nStartPos = new long[nCount]; /Ps/m!
nEndPos = new long[nCount]; 8A'oK8Q
for(int i=0;i<nStartPos.length;i++) QMwrt
{ 3)cH\gsg9
nStartPos = input.readLong(); AAuH}W>n
nEndPos = input.readLong(); >BFUts%
} X\sOeb:]
input.close(); YS],o'T
} C&wp*
catch(IOException e){e.printStackTrace ();} $`;1][OD
catch(Exception e){e.printStackTrace ();} r}T(?KGx
} ?V&#nA
N5_`
wo>7^ZA
private void processErrorCode(int nErrorCode) ,58XLu
{ {8]Yqx)1]]
System.err.println("Error Code : " + nErrorCode); @:s(L]
} tx`gXtO$
BRSIg]
inQ1$
//停止文件下载 {+Zj}3o
public void siteStop() ^`iqa-1
{ ^jhc(ZW"
bStop = true; GW{e"b/x
for(int i=0;i<nStartPos.length;i++) &;3iHY;
fileSplitterFetch.splitterStop(); g A+p^`;[
Y.yiUf/Q
AdU0 sZ+&c
} _"l2UDx
} f^Io:V\
//负责部分文件的抓取 t9l]ie{"o.
**FileSplitterFetch.java E>_N|j)9
*/ 1#tFO
package NetFox; n Nu~)X
{gT4Oq__
{3Y R_^>?
import java.io.*; = q\TWz
import java.net.*; yjE$o?A
emT/5'y
\gCh'3
public class FileSplitterFetch extends Thread { {HO,d{{
&s^t~>Gpr
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String sURL; //File URL _|jEuif
long nStartPos; //File Snippet Start Position ZX0#I W
long nEndPos; //File Snippet End Position 0q6xXNAX
int nThreadID; //Thread's ID CXiDe)|<E
boolean bDownOver = false; //Downing is over V*6o|#
boolean bStop = false; //Stop identical DMdVE P"m
FileAccessI fileAccessI = null; //File Access interface h~`^H9?M
kY?w] lS)t
>Py:9~g,
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException )Szn,
{ + *)Kyk
this.sURL = sURL; xYp-Y"a.
this.nStartPos = nStart; 9ERyr1-u v
this.nEndPos = nEnd; l~Hu#+O
nThreadID = id; i"`N5
fileAccessI = new FileAccessI(sName,nStartPos);//定位 :lU#Dm]
} 0}mVP
w<LV5w+
X<sM4dwxE
public void run() :8t;_f
{ )ko[_OJj
while(nStartPos < nEndPos && !bStop) Bv xLbl}
{ =JaxT90x
FJD;LpW
'ws@I?!r
try{ H#H[8#
URL url = new URL(sURL); O$ARk+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); }vxRjO,
httpConnection.setRequestProperty("User-Agent","NetFox"); gySl.cxt
String sProperty = "bytes="+nStartPos+"-"; ]P*H,&I`#
httpConnection.setRequestProperty("RANGE",sProperty); U! $/'Xi9
Utility.log(sProperty); qDS~|<Y5
<5!)5+G
I]ZksC
InputStream input = httpConnection.getInputStream(); r XT6u
//logResponseHead(httpConnection); K-b`KcX
3~%M4(
:sX4hZK=G
byte[] b = new byte[1024]; 9 lXnNK |]
int nRead; qTz5P
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) SFjRSMi
{ f"-3'kqo
nStartPos += fileAccessI.write(b,0,nRead); GJ\bZ"vDo
//if(nThreadID == 1) /$d#9Uv
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Y)68
} )YVs=0j
$sFqMy
#AH gY.
Utility.log("Thread " + nThreadID + " is over!"); l0r^LK$
bDownOver = true; B{K_?ae!
//nPos = fileAccessI.write (b,0,nRead); g;~$xXn
} &})Zqc3Lqk
catch(Exception e){e.printStackTrace ();} ,&iEn}xG7i
} emHaZhh
} gI/SA
gb=tc`
siOyp]
//打印回应的头信息 KwY6pF*
public void logResponseHead(HttpURLConnection con) +3J5j+
{ uHuL9Q^
for(int i=1;;i++) qN'%q+n
{ 0HI0/Tvu$<
String header=con.getHeaderFieldKey(i); z s\N)LyM
if(header!=null) FwV5{-(
//responseHeaders.put(header,httpConnection.getHeaderField(header)); I@kMM12>c
Utility.log(header+" : "+con.getHeaderField(header)); ~zoZ{YqP
else S;"$02]
break; J;k8 a2$_
} E J&w6),d
} h ^Wm03w
)_kU,RvZ
(g>&ov(d
public void splitterStop() * $|9e
{ jA3xDbM
bStop = true; 3F9dr@I.7
} lQL/I[}
F6ZL{2$k@
IK,aA;d
} /tJ%gF
m0*_
3 jghV?I{T
/* -+0!Fkt@,
**FileAccess.java &23{(]eO
*//文件访问(定位，写) geNvp0
package NetFox; CpU y~
import java.io.*; $'w>doUlA
Yq:+.UU
fM3ZoH/
public class FileAccessI implements Serializable{ gMPvzBpP
#<5i/5&
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 i'`>YX
RandomAccessFile oSavedFile; r@CbhD
long nPos; qhmA)AWG>
[M?&JA_$}
(r-PkfXvIf
public FileAccessI() throws IOException ;m"R.Q9*
{ acI%fYw5p`
this("",0); CtHsi8m
} 2U3WH.o
IIAm"=*
QSvgbjdE
public FileAccessI(String sName,long nPos) throws IOException xgIb4Y%
{ >Ft:&N9L{
oSavedFile = new RandomAccessFile(sName,"rw"); -K4uqUp
this.nPos = nPos; Lw6}bB`}
oSavedFile.seek(nPos); HHZrovA#
} #&Zj6en}M]
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!Xzy:
public synchronized int write(byte[] b,int nStart,int nLen) V0*9Tnc
{ `8D'r|=`Eh
int n = -1; gFxaUrZA
try{ 4EJ6Zy![0*
oSavedFile.write(b,nStart,nLen); 5Y5N
n = nLen; mSp;(oQ
} CMfR&G,)
catch(IOException e) `o%Ua0x2
{ 6z5?9I4[
e.printStackTrace (); ~./M5P!\
} WE&"W$0
b|U3\Fmc
b(_PV#@$
return n; 5xc-MkIRL
} `3vt.b
b@[\+P] "
?r R, h{~
} H?j}!JzAC
-l$-\(,M`#
^%x7:
/* 7.B]B,]
**SiteInfoBean.java Cce{aY
*/ 74a>}+"
package NetFox; [4HOWM>\
SI;SnF'[7
_UUp+Hz
public class SiteInfoBean { s ]Db<f
k^\>=JTq=
6zJ>n~&(
private String sSiteURL; //Site's URL MU~nvs;:
private String sFilePath; //Saved File's Path FhMl+Ou
private String sFileName; //Saved File's Name zqb3<WP"
private int nSplitter; //Count of Splited Downloading File Zc*gRC
^4tz*i
E"b"VB
public SiteInfoBean() ysQ8==`38i
{//nSplitter的缺省值为5 CfjVx
//default value of nSplitter is 5 ~[ x}
this("","","",5); lISu[{b?
} 3EX41)u
\"mLLnK?
:_+Fe,h>|
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) O\zGN/!
{ }t.VH:02y
sSiteURL= sURL; D(Yq<%Q
sFilePath = sPath; b{lkl?@a
sFileName = sName; u9)<i]2
this.nSplitter = nSpiltter; <utD&D8w
+X7+:QQ}
3gY4h*|`<
} RLX?3u&
W\<p`xHk
oF#]<Z\
public String getSSiteURL() m_r_4BP
{ ( O/+.qb
return sSiteURL; `xd{0EvF
} hh"=|c
(Y?"L_pC
[<7Vv_\Q
public void setSSiteURL(String value) .+hM1OF`x
{ ""^.fh
sSiteURL = value; a |+q:g0M
} kDr0D$iE
b7? 2Pu
[lX3":)
public String getSFilePath() I4^}C;p0?
{ $NhKqA`0
return sFilePath; ;&G8e*bM2
} +BE_K_56
C~a-R#
$@:z4S(
public void setSFilePath(String value) 7nL3+Pq
{ b<mxf\b
sFilePath = value; /=2
} (@1*-4l
hh>mX6A
ckPI^0A!
public String getSFileName() f")*I
{ J|2OmbJe
return sFileName; QGV~Y+
} 0`dMT>&I
o`]u&
XK4idC
public void setSFileName(String value) 4`#3p@-
{ /|2#s%|-=
sFileName = value; ghd*EXrF H
} 1f^4J~{
C) "|sG
*R^ulp[W
public int getNSplitter() h_Cac@F0
{ G(XI TL u*
return nSplitter; *k#M;e
} Ii9@ j1-g
)pAN_e"
yPqZ ,
public void setNSplitter(int nCount) aj<=]=hr
{ `+/xA\X]
nSplitter = nCount; Ge]2g0
} ;f7;U=gl,
} idr,s\$>
Z:PsQ~M
9V=bV=4:
/* GKNH{|B$D
**Utility.java l[q%1-N
*/ $Z;?d@6yI
package NetFox; -Vi"hSsUP
tj_+0J$sw:
&[hq !v
public class Utility { 1>SCY_Cv
~"+Fp&[9f
9\]%N;;Lo
public Utility() - zQ
{ '<C I^5^
|NcfR"[c
Y(4#b`k3
} D{aN_0mT
\=yx~c_$L
//线程睡眠 \HB4ikl
public static void sleep(int nSecond) ;O2r+n
{ |?!Ew# w
try{ "gD)Uis
Thread.sleep(nSecond); {yy^DlHb
} G2%%$7Jj
catch(Exception e) dw60m,m
{ U'st\Dt
e.printStackTrace (); iG1vy'J#o
} ncluA~8
} /?jAG3"
tndtwM*B'
//日志 &\$l%icuo
public static void log(String sMsg) &r6VF/
{ ~(xIG
System.err.println(sMsg); s|U?{Byb!
} `V@{#+X
u$N2uFc
#KonVM(`
public static void log(int sMsg) f.`noZN
{ -O2ZrJ!q
System.err.println(sMsg); CqUK[#kW(
} a(X?N.w
} p AzPi
$e;_N4d^
^3Ni
/* N4%q-fi
**TestMethod.java ~h] <E
*/ RpE69:~PV
package NetFox; Y" s1z<?
pC2r{-
oY:6a
public class TestMethod { 9&=~_,wJd
`/'Hq9$F<"
5A:mu+Iz6H
public TestMethod() Nw}y_Qf{
{ ///xx/weblogic60b2_win.exe !aD/I%X
try{ Zi=Nr3b
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Y?2I /
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); M`ETH8Su=
SiteFileFetch fileFetch = new SiteFileFetch(bean); 3y%B&W,sm
fileFetch.start(); c,1Yxg]|
} ?Ovl(4VG
catch(Exception e){e.printStackTrace ();} cbl2D5s+i]
1pC!F ;9Oo
8YAUy\
} 0+0+%#?
e g#.f`
u0^: XwZ!
public static void main(String[] args) E0^~i:Mk
{ :luVsQ
new TestMethod(); h5&l#>8&
} NamBJ\2E1[
} bE2^sx`(
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