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)); ?W\KIp\Kn
} 08_<G`r
for(int i=0;i<nEndPos.length-1;i++) X- P%^mK
{ 3U9leY'2N
nEndPos = nStartPos[i+1]; L~!Lq4]V\g
} 0 } |21YED
nEndPos[nEndPos.length-1] = nFileLength; ,?c=v`e
} l{8t;!2t
} 9/PX~j9O?
'NN3XyD
BmFtRbR
//启动子线程 ^0(`:*
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; q rF:=?`E
for(int i=0;i<nStartPos.length;i++) G7k.YtW
{ c|F26$rv
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Z|BOuB^
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 9Idgib&
nStartPos,nEndPos,i); 5|g#>sx>`q
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); hY/i)T{
fileSplitterFetch.start(); !|-:"hE1h
} g+QNIM>
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), tN_~zP
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); :1gcLsF
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", >K 7]G?+7E
nEndPos = " + nFileLength); (Eo#oX
// fileSplitterFetch[nPos.length-1].start(); D6:"k 2
fO}Y$y\q
P,bis7X.
//等待子线程结束 _Kv;hR>
//int count = 0; IFkU8EK&B
//是否结束while循环 *lyRy/POB
boolean breakWhile = false; y<^hM6S?Z
W:1GY#Pe
jF6[+bW<
while(!bStop) 66'AaA;0^i
{ IRbZ ;*3dO
write_nPos(); r1zuc:W1
Utility.sleep(500); x?2y^3<5
breakWhile = true; (P 9$Ei0fv
2l}3L
0c]3 ,#
for(int i=0;i<nStartPos.length;i++) puK /;nns
{ Ql9 )
if(!fileSplitterFetch.bDownOver) #IxCI)!I{[
{ $`txU5#vs
breakWhile = false; [p96H)8YU
break; }^ZPah
} ca"20NQ)
} Y4)=D@JI
if(breakWhile) p2j=73$
break; jEW@~e
r~sQdf
!;B^\ 8{
//count++; KTjf2/
//if(count>4) cB4p.iO
// siteStop(); PHqIfH[
} ZZU"Q7`^
' 4Kf
W_ubgCB
System.err.println("文件下载结束！"); 7_]Bu<{f
} /@9-D 4
catch(Exception e){e.printStackTrace ();} pd oCV
} *_tJ;
k1_3\JO"6
E{E%nXR)
//获得文件长度 :\,3=suWq
public long getFileSize() X-J<gI(Y
{ Ng1uJa[k!d
int nFileLength = -1; Y?V>%eBu
try{ ]F1ZeAh5
URL url = new URL(siteInfoBean.getSSiteURL()); S<DS|qOo
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); >TwL&la
httpConnection.setRequestProperty("User-Agent","NetFox"); P*6&0\af|
MUqV$#4@I
)Tj\ym-Vl
int responseCode=httpConnection.getResponseCode(); J2Eb"y>/;
if(responseCode>=400) -,}ppTG
{ 'E~[I"0
processErrorCode(responseCode); 2Ls
return -2; //-2 represent access is error \7A6+[ `fa
} roE*8:Y
*m`KY)b=l
Auf2JH~
String sHeader; jl~?I*Gr
wEJ?Y8
($Y6hn+
for(int i=1;;i++) a%)-iL X8&
{ "ju0S&
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); R{A$hnhW6
//Utility.log(in.readLine()); %SD=3UK6
sHeader=httpConnection.getHeaderFieldKey(i); %2TjG
if(sHeader!=null) U#1,]a\
{ 06~HVv
if(sHeader.equals("Content-Length")) d=8q/]_p
{ u7kw/_f
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); psZ #^@>mJ
break; tQrkRg(E:
} xbhU:,o
} cQldBc
else l]v>PIh~N
break; Rjz~n38.
} :Vx5%4J
} RE}$(T=
catch(IOException e){e.printStackTrace ();} ({#M*=&"
catch(Exception e){e.printStackTrace ();} i& ybvTl
(lR9x6yf
<X1^w
Utility.log(nFileLength); h?ZxS
x"QZ}28(t
[p# }=&d
return nFileLength; yZ]u{LJS
} JJ$q*
a'2^kds
CN, oH4IU
//保存下载信息（文件指针位置） ]:vo"{*C
private void write_nPos() &o$Pwk\p/
{ enJgk(
try{ 6!^&]4
output = new DataOutputStream(new FileOutputStream(tmpFile)); QSq0{
output.writeInt(nStartPos.length); v\:P_J
for(int i=0;i<nStartPos.length;i++) m'P,:S)=
{ { |[n>k
// output.writeLong(nPos); aZ{]t:]
output.writeLong(fileSplitterFetch.nStartPos); I?!7]Sn$
output.writeLong(fileSplitterFetch.nEndPos); k(.6K[b
} 1y($h<
output.close(); /vLdm-4
} D!d1%hac
catch(IOException e){e.printStackTrace ();} 2[qlEtvQ
catch(Exception e){e.printStackTrace ();} +*aZ9g
} *eonXJYD
Juqe%he`
8Cw+<A*
//读取保存的下载信息（文件指针位置） U%nLo[k
private void read_nPos() u+Q<>>lU
{ a2'f#[as
try{ ,aBo p#
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); >=Pn\"j
int nCount = input.readInt(); :v>Nz7SB
nStartPos = new long[nCount]; z<c%Xl\$%
nEndPos = new long[nCount]; .V Cfh+*J#
for(int i=0;i<nStartPos.length;i++) ^yo~C3r~
{ $'obj
nStartPos = input.readLong(); T,D(Xh
nEndPos = input.readLong(); CFU'- #b
} 96FS-`
input.close(); z nxAP|
} ')mR87
catch(IOException e){e.printStackTrace ();} jA}b=c
catch(Exception e){e.printStackTrace ();} yhpeP
} p\ }Ep
vz-O2B_u
$+$S}i=
private void processErrorCode(int nErrorCode) ,=@%XMS
{ O.% $oV
System.err.println("Error Code : " + nErrorCode); :]hNw1e
} J*} warf&
s}3`%?,6y
m=hUHA,p4
//停止文件下载 qXw^y
public void siteStop() Ob#d;F
{ TppuEC>
bStop = true; fT.GYvt`
for(int i=0;i<nStartPos.length;i++) ]'iOV-2^'
fileSplitterFetch.splitterStop(); q&RezHK l
C6T?D5
T7bDt
} b&j}f
} RU_wr<
//负责部分文件的抓取 0;V "64U
**FileSplitterFetch.java / !@@
*/ Adma~]T9
package NetFox; L" GQQ
=W_Pph
d~F4
import java.io.*; .*(xkJI3
import java.net.*; 4Lb!Au|Y
~0 Ifg_G
GWvw<`4
public class FileSplitterFetch extends Thread { 0mMoDJRy
%qYiE!%&
t3// U#
String sURL; //File URL Glw_<ag[
long nStartPos; //File Snippet Start Position qTuQ]*[-
long nEndPos; //File Snippet End Position miTySY6^
int nThreadID; //Thread's ID ~>"m`Q&[
boolean bDownOver = false; //Downing is over zvgy$]y'\
boolean bStop = false; //Stop identical !Enq2
FileAccessI fileAccessI = null; //File Access interface Ump$N#
gZHuyp(B
:+qd>;yf#
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Y*Ra!]62
{ ls*bCe
this.sURL = sURL; H6t'V%Ys
this.nStartPos = nStart; \QvoL
this.nEndPos = nEnd; wJ%;\06
nThreadID = id; ,ut-Di=6
fileAccessI = new FileAccessI(sName,nStartPos);//定位 CVt:tV
} ^tTASK
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cM hBOm*
public void run() rijavZS6
{ V*<`!w
while(nStartPos < nEndPos && !bStop) qbsmB8rh
{ y<5RV>"Vg
u$38"&cmA
!ay:h Iv
try{ o^ zrF
URL url = new URL(sURL); y9)w(y!
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); pv[Gg^
httpConnection.setRequestProperty("User-Agent","NetFox"); !Soz??~o/
String sProperty = "bytes="+nStartPos+"-"; je`Ysben
httpConnection.setRequestProperty("RANGE",sProperty); JJZu%9~[
Utility.log(sProperty); rLpfybu
NxW Dw
ki6Lt
InputStream input = httpConnection.getInputStream(); h0O t>e"
//logResponseHead(httpConnection); b$;qtfJG
\5iMr[s
{)jTq??
byte[] b = new byte[1024]; }] p9
int nRead; Fc6o6GyL|o
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Ls`[7w
{ 0H/)wy2ym
nStartPos += fileAccessI.write(b,0,nRead); d@XXqCR<
//if(nThreadID == 1) U #C@&2
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); akA7))Q
} SNJSRqWL/
dM=45$\q
tiGBjTPt
Utility.log("Thread " + nThreadID + " is over!"); jP{&U&!i
bDownOver = true; yiw4<]{IX
//nPos = fileAccessI.write (b,0,nRead); `+m:@0&L
} abD@0zr
catch(Exception e){e.printStackTrace ();} lDSF
} 5MCnGg@
} ve]hE}o/}
dfP4SJqq
@9tzk [
//打印回应的头信息 lQM&q
public void logResponseHead(HttpURLConnection con) sg8[TFX@Z
{ hm*cGYV/
for(int i=1;;i++) *\(MG|S
{ ~ \]?5 nj
String header=con.getHeaderFieldKey(i); V1&qgAy~
if(header!=null) L</k+a?H!
//responseHeaders.put(header,httpConnection.getHeaderField(header)); RY .@_{
Utility.log(header+" : "+con.getHeaderField(header)); .He}f,!f<
else ^6On^k[|fw
break; l0 8vF$k|d
} xG(xG%J
} bu9.HvT'
GXp`yK9c
'Qh1$X)R7a
public void splitterStop() T-LX>*
{ kV+%(Gl8
bStop = true; c'.XC}
} 2 EWXr+IU.
bp!Jjct
O9C&1A|lA
} eaAGlEW6J
[{$%9lm
Bd]k]v+
/* /%mT2
**FileAccess.java ;1HzY\d%<
*//文件访问(定位，写) ]rG/?1'^i
package NetFox; /9e?uC6
import java.io.*; n$F~
Fw S>V2R
9=mc3m:Tb(
public class FileAccessI implements Serializable{ 1<tJ3>Xl
i!x>)E
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 en'"" w
RandomAccessFile oSavedFile; wRvh/{xB
long nPos; =EYWiK77a
[l3ys
<5?pa3
public FileAccessI() throws IOException o_1N "o%
{ ]rv4O@||w
this("",0); Z5E; FGPb
} E.Q]X]q
AhD C5ue=
sH.=Faos
public FileAccessI(String sName,long nPos) throws IOException z %Bzf~N9
{ @c-
oSavedFile = new RandomAccessFile(sName,"rw"); W6Mq:?+D
this.nPos = nPos; '4nJ*Xa
oSavedFile.seek(nPos); D#AqZS>B
} kU+|QBA@
Zwm/c]6`
W#%s0EN<_
public synchronized int write(byte[] b,int nStart,int nLen) f1]zsn:
{ lxm/*^
int n = -1; R8cOb*D
try{ D<m0G]Ht*
oSavedFile.write(b,nStart,nLen); X@"G1j >/
n = nLen; mU]VFPr5
} [ /YuI@C,@
catch(IOException e) \ )=WA!
{ wk ^7/B
e.printStackTrace (); {fnx=BaG
} W|D kq
m`l9d4p w?
FJDE48Vi
return n; <sw@P":F
} "(3u)o9
f"KrPx!^b
\XPGA uEo
} <^\rv42'(2
j)2I+[aoB
T8|5%Y
/* &iInru3
**SiteInfoBean.java D8<C7
*/ 37$ ^ie)
package NetFox; A*eVz]i,k&
*I)J%#
>v%js!`f
public class SiteInfoBean { J09jBQ]R
y?&hA!x
kzjuW
private String sSiteURL; //Site's URL =KUmvV*\
private String sFilePath; //Saved File's Path a3>/B$pE
private String sFileName; //Saved File's Name :{#O
private int nSplitter; //Count of Splited Downloading File odSPl{.>d
G0{Z@CvO'
>UMxlvTg&
public SiteInfoBean() 4SZ,X^]I>
{//nSplitter的缺省值为5 1vxRhS&FY
//default value of nSplitter is 5 P+0'^:J
this("","","",5); Lxwi"ndP
} eD?&D_l~6
ly-(F2
W;'fAohr
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) E?G'F3i
{ J7* o%W*V
sSiteURL= sURL; uMEM7$o
sFilePath = sPath; b!P,+!<
sFileName = sName; CtXbAcN2B
this.nSplitter = nSpiltter; V6X )L>!xx
'< U&8?S
-BH/)$-$
} O|V0WiY<
!,$#i
J(l\VvK
public String getSSiteURL() :YI5O/gsk?
{ $Lr&V~
return sSiteURL; 4AS%^&ah
} zak\%yY`
,7LfvZj4[
B;r_[^
public void setSSiteURL(String value) 2ZY$/
{ &em~+83
sSiteURL = value; W;Y^(f
} :$$~$P
nbF<K?
}6@E3z]AMO
public String getSFilePath() hBjU(}\3
{ ZC N}iQu4
return sFilePath; LUbj^iQ9
} %dzt'uz
TP rq:"K
NX&dJ 6a
public void setSFilePath(String value) He(65ciT<O
{ Jy)=TJ!y
sFilePath = value; Nvgi&iBh8
} i%-yR DIX
Q>,&@
z2iMpZ
public String getSFileName() (oGYnN,2
{ xoKK{&J
return sFileName; Byc;r-Q5V
} J'}+0mln
]p`y
l8FJ\5'M
public void setSFileName(String value) 5vyg-'
{ s<zN`&t
sFileName = value; lxyTh'
} )8A.Wg4S;c
!:&SfPv
+]eG=. u
public int getNSplitter() M-nRhso
{ i1cd9
return nSplitter; 0vqVE]C
} J\y^T3Z
I=kqkuW
O>' }q/
public void setNSplitter(int nCount) 1 pVw,}
{ .;4N:*hY
nSplitter = nCount; 9^XZ|`
} ^I!Z)/
} tnJ7m8JmC
O2Qmz=%
MJ JC6:
/* [P &B
**Utility.java EHwb?{
*/ klUV&O+=%
package NetFox; FOQ-KP\=,
[c3!xHt5O
3Y)&[aj
public class Utility { }_nBegv
rRRh-%.RU
.V hU:_u
public Utility() .b,\.0N
{ JKZVd`fF
G`!,>n 3
j2D!=PK;
} sE?%;uBb
OkciL]
//线程睡眠 %unn{92)
public static void sleep(int nSecond) @} r*KF-
{ PaaMh[OmG
try{ B~I ]3f
Thread.sleep(nSecond); ,7B7X)m{3
} P8YnKyI,.
catch(Exception e) BQ6$T&
{ 6]1RxrAV
e.printStackTrace (); L ci?
} -dM~3'
} B&_:20^y~
\^(#b,k#
//日志 }rJqMZ]w
public static void log(String sMsg) 6|EOB~|
{ -9om,U`t
System.err.println(sMsg); R|RGoGE6g
} MGF!ZZ\
JPDxzp
lf(+]k30
public static void log(int sMsg) wrkw,H
{ P'Y(f!%
System.err.println(sMsg); spA|[\Nl
} 96\FJHtZ
} $*{,Z<|2
;l;jTb^l
%g7j7$c
/* 16Qu{K
**TestMethod.java )j8'6tk)Z
*/ oc"p5Y3,Os
package NetFox; 'gN[LERT
tV=Qt[|@
?*~ ~Ok
public class TestMethod { [\ku,yd%0
$(62j0mS>
;rf{T[i
public TestMethod() >7WT4l)7!b
{ ///xx/weblogic60b2_win.exe .Yk}iHcW.
try{ F7}yt
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 5i6Ji(
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); )P7oL.)
SiteFileFetch fileFetch = new SiteFileFetch(bean); \ ERBb.
fileFetch.start(); w?D=
} A@3'I ;
catch(Exception e){e.printStackTrace ();} 'cCM[P+
ar@,SKU'K
~[!Tpq5
} d*TH$-F!p
yHY2 SXm
_Q #[IH9
public static void main(String[] args) [p4([ef '
{ #IppjaPl8
new TestMethod(); CM~x1f*v
} {v!w2p@
} v1$}[&/
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