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)); c`lL&*]
} /FPO'} 6i
for(int i=0;i<nEndPos.length-1;i++) Wk/Q~o
{ -Ks)1w>l
nEndPos = nStartPos[i+1]; 7o!t/WEEq
} I7Abf7>*Q
nEndPos[nEndPos.length-1] = nFileLength; 5t_Dt<lIz
} 6iEg]FI
} @/$i -?E
!>Q\Y`a,*
Sz1J4$5
//启动子线程 q?]KZ_a
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; aAn p7\7
for(int i=0;i<nStartPos.length;i++) 017nhI
{ 8o $` '
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), .Xe_Gp"x
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 368 g>/#'
nStartPos,nEndPos,i); rqm":N8@
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); -w)v38iX!
fileSplitterFetch.start(); /f+BeQ3#/
} hPgYKa8u
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), pSYEC,0B
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); SsfC m C
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", CMv8n@ry
nEndPos = " + nFileLength); e?O$`lf
// fileSplitterFetch[nPos.length-1].start(); Vl<7>
~P~q'
OmfHrlA
//等待子线程结束 S-7C'dc
//int count = 0; 8.IenU9
//是否结束while循环 q3K}2g
boolean breakWhile = false; DeT$4c*:[
/Q:mUd
01RW|rN
while(!bStop) 7xG~4N<)]
{ QJjk#*?,|
write_nPos(); ;3bUgI}.J
Utility.sleep(500); f3>DmH#
breakWhile = true; :B7U),T
x1E;dbOZ
gMPp'^g]_
for(int i=0;i<nStartPos.length;i++) ]P>XXE;[
{ BD^1V( I/
if(!fileSplitterFetch.bDownOver) S9%,{y
{ .EH1;/
breakWhile = false; Y"m(hs$
break; 88?O4)c
} )24M?R@r
} !gfd!R
if(breakWhile) aS\$@41"
break; tB(~:"|8
&"J;
fYh<S
//count++; P46Q3EE
//if(count>4) M1*bT@6
// siteStop(); H?xYS| n
} 5)hfI7{d
@tD (<*f+
k{UeY[,jb
System.err.println("文件下载结束！"); CHD.b%_|
} A&WC})H5
catch(Exception e){e.printStackTrace ();} L<Z,@q`
} u3tT=5.D
\ a(ce?C
/5j5\F:33
//获得文件长度 R*S:/s
public long getFileSize() @_#\qGY
{ rcY &n^:
int nFileLength = -1; ,j.bdlI#
try{ &%t&[Se_~
URL url = new URL(siteInfoBean.getSSiteURL()); 3Z&!zSK^
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); FC+h \
httpConnection.setRequestProperty("User-Agent","NetFox"); 0\@oqw]6hv
V@O)7ND
C4|OsC7J
int responseCode=httpConnection.getResponseCode(); OIjSH~a.
if(responseCode>=400) @>V;guJC%
{ -%^'x&e
processErrorCode(responseCode); UEfY'%x
return -2; //-2 represent access is error urCTP.F
} ~{vB2
J1~E*t^
!=a]Awr\
String sHeader; \^RKb-6n
?A*!rW:l;
3T4HX|rC
for(int i=1;;i++) Zzz94`
{ K4YD}[
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 7v0AG:
//Utility.log(in.readLine()); =oI6yf&8 Z
sHeader=httpConnection.getHeaderFieldKey(i); n+YUG
if(sHeader!=null) ecQ,DOX|b
{ 10OkrNQ
if(sHeader.equals("Content-Length")) uKvdL "
{ g-"GZi
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); c$tX3ug6I
break; :XG~AR/
} %2g<zdab
} 1<_/Qu>V
else AYNdV(
break; |5X[/Q*K`W
} H6|eUU[&
} =adHP|S
catch(IOException e){e.printStackTrace ();} IAq o(Qm
catch(Exception e){e.printStackTrace ();} d%-/U!z?
W g6H~x
iemp%~UZ
Utility.log(nFileLength); RwOOe7mv
SPt/$uYJ
c<MF:|(}
return nFileLength; =+ >>l0=_v
} @h!Z0}dX(
jC{KI!kPt
TO"Md["GI
//保存下载信息（文件指针位置） 83gWA>Odh
private void write_nPos() eNVuw:Q+
{ u'>94Gm}
try{ A>2_I)
output = new DataOutputStream(new FileOutputStream(tmpFile)); NMf#0Nz-
output.writeInt(nStartPos.length); g=@d!]Z~[
for(int i=0;i<nStartPos.length;i++) ^+CHp(X
{ ~!8j,Bqs+z
// output.writeLong(nPos); QKlsBq
output.writeLong(fileSplitterFetch.nStartPos); f86Z #%
output.writeLong(fileSplitterFetch.nEndPos); *pv<ZF0>
} q^Oj/ws
output.close(); : MjDcI~
} ov;^ev,(
catch(IOException e){e.printStackTrace ();} +jF2{"
catch(Exception e){e.printStackTrace ();} c"Vp5lo0
} Yv@n$W`:
WulyMcJ
jlU6keZh`
//读取保存的下载信息（文件指针位置） vB{iw}Hi!
private void read_nPos() OWT%XUW=
{ .SER,],P
try{ C c:<F_UI
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); "`4ky]
int nCount = input.readInt(); {ilz[LM8(
nStartPos = new long[nCount]; <r t$~}
nEndPos = new long[nCount]; z8JW iRn
for(int i=0;i<nStartPos.length;i++) [WG\wj.
{ *qk7e[IP
nStartPos = input.readLong(); liH#=C8l*%
nEndPos = input.readLong(); 'Kbrz
} wL="p) TO.
input.close(); t&J A1|q
} seBmhe5qR
catch(IOException e){e.printStackTrace ();} >Bf3X&uS
catch(Exception e){e.printStackTrace ();} 2%`= LGQC
} +,LWyvc'
4_U"M@
dgoAaS2M
private void processErrorCode(int nErrorCode) OoH-E.lp
{ W.jXO"pN
System.err.println("Error Code : " + nErrorCode); .O5V;&,
} m:[I$b6AY
Q[rZ1z
UF#!6"C@
//停止文件下载 jga\Ry=nw
public void siteStop() 9,`i[Dzp
{ rVoV@,P
bStop = true; T>rmm7F
for(int i=0;i<nStartPos.length;i++) V@#oQi*
fileSplitterFetch.splitterStop(); ob;|%_
z06,$OYz
/YHO"4Z
} d-+jb<C&
} 3-{BXht)
//负责部分文件的抓取 3c3;8h$k
**FileSplitterFetch.java 'kcR:5B
*/ aXJ/"k #Tl
package NetFox; 72Y6gcg
NGl 8*Af
3,{eH6,O7M
import java.io.*; ,S=[#
import java.net.*; rD SYR\cg
9|Jv>Ur=)2
9 $$uk'}w!
public class FileSplitterFetch extends Thread { \+O.vRc"M
Z6i~Dy3
PD.$a-t
String sURL; //File URL )-Hs]D:
long nStartPos; //File Snippet Start Position }" vxYB!h3
long nEndPos; //File Snippet End Position gI;"PkN
int nThreadID; //Thread's ID `7:uc@
boolean bDownOver = false; //Downing is over eQu(3sYb
boolean bStop = false; //Stop identical NF6xKwRU]_
FileAccessI fileAccessI = null; //File Access interface {Fw"y %a^
Rq5'=L
s~A-qG>
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Lxv4w
{ goIvm:?
this.sURL = sURL; ~. vridH
this.nStartPos = nStart; S1U0sP@o
this.nEndPos = nEnd; ;98b SR/
nThreadID = id; o&E8<e
fileAccessI = new FileAccessI(sName,nStartPos);//定位 eb\SpdM6
} aM;SE9/U
Y_:jc{?
b3E1S+\=~
public void run() S=!WFKcJR
{ <7\j\`
while(nStartPos < nEndPos && !bStop) i3N{Dt
{ (is',4^b
$ItmYj.m
D0FX"BY7
try{ m.m6.
URL url = new URL(sURL); :&vX0 Ce:
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); j}ob7O&U'w
httpConnection.setRequestProperty("User-Agent","NetFox"); 0@-4.IHl
String sProperty = "bytes="+nStartPos+"-"; FDLo|aP/v
httpConnection.setRequestProperty("RANGE",sProperty); [8sYEh
Utility.log(sProperty); KQNQ<OE4
[q2:d^_FA
OlRXgJ
InputStream input = httpConnection.getInputStream(); 4@{cK|
//logResponseHead(httpConnection); $lf/Mg_H
t2(X
.))jR:{3
byte[] b = new byte[1024]; =eU=\td^
int nRead; vYm:V:7Y2
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) "@eGgQ
{ /f1]U LmC:
nStartPos += fileAccessI.write(b,0,nRead); Q/4-7
//if(nThreadID == 1) t[`LG)
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Gg'!(]v
} .T9$O]:o
QX<n^W
A,<5W }
Utility.log("Thread " + nThreadID + " is over!"); .Q!d[vL
bDownOver = true; 0>BxS9?w
//nPos = fileAccessI.write (b,0,nRead); y2_rm
} 1]Xx{j<
catch(Exception e){e.printStackTrace ();} IAH"vHM
} }S uj=oFp
} 8j#S+=l>
1DB{"8ov
M=Ze)X\E*'
//打印回应的头信息 DlUKhbo$g
public void logResponseHead(HttpURLConnection con) Q`9c/vPU
{ UXBWCo;-
for(int i=1;;i++) 1,+<|c)T?
{ gD6S%O
String header=con.getHeaderFieldKey(i); aKriO
if(header!=null) }g/u.@E
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 4)w,gp
Utility.log(header+" : "+con.getHeaderField(header)); Z|n|gxe
else {O2=K#J
break; +s}&'V^
} q!:dZES
} [n[dr@J7v
U=~?ca
*0>`XK$mWo
public void splitterStop() MT~^wI0a
{ ]!{S2x&"
bStop = true; ]M*`Y[5"
} D5c 8sB
u @Ze@N%
=l43RawAmu
} W9%v#;2
A,_O=hA2I
; R+>}6
/* T-a>k.}y
**FileAccess.java e n~m)r3&
*//文件访问(定位，写) Qf( A
package NetFox; T5u71C_wmt
import java.io.*; Q^f{H.
4}m9,
b M1\z
public class FileAccessI implements Serializable{ i4|R0>b
AaYH(2m-
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 !ddyJJ^a
RandomAccessFile oSavedFile; Q[#}Oh6$
long nPos; ^ 0YQlT98
>*{k~Y-G
P$U"y/
public FileAccessI() throws IOException H\QkU`b
{ W\zZ&*8$
this("",0); J~5V7B
} S9l,P-X`
zE/l
wvq4 P
public FileAccessI(String sName,long nPos) throws IOException +XsE
{ _ACN
oSavedFile = new RandomAccessFile(sName,"rw"); 1jd{AqHl
this.nPos = nPos; VH]}{i"`
oSavedFile.seek(nPos); yIKpyyC9H
} _!o8s%9be
$!*>5".A
/3aW 0/^o
public synchronized int write(byte[] b,int nStart,int nLen) @KL&vm(F$
{ F^gTID
int n = -1; Bn]=T
try{ E_=F'sP?
oSavedFile.write(b,nStart,nLen); $97O7j@
n = nLen; /8e}c`
} cRf F!EV
catch(IOException e) CImp,k0
{ xw9ZRu<z
e.printStackTrace (); F~6]II
} ,5$G0
Fy{yg]O"
;<garDf
return n; R278^E
} N-upNuv
[<53_2]~
Eto"B"
} YAc:QVT87
<ZSXOh,'
`w 6Qsah
/* HMF2sc$N
**SiteInfoBean.java \eKXsO"d
*/ @~$d4K y<
package NetFox; >}*W$i
:o8`2Z*g
nz?[
public class SiteInfoBean { xJ$uoy3+
#S?^?3d
%8n<#0v-|4
private String sSiteURL; //Site's URL u*@R`,Y
private String sFilePath; //Saved File's Path ! :]_-DX
private String sFileName; //Saved File's Name #$BFTlm|
private int nSplitter; //Count of Splited Downloading File }eVDe(7_
72Bc0Wg
et+lL"&
public SiteInfoBean() B9NUafK=
{//nSplitter的缺省值为5 X6 BIZ
//default value of nSplitter is 5 sR9$=91`
this("","","",5); !tTv$L>
} ,CyX*k8o
&'/"=lK
}9\_s*
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) J`5+Zngr
{ 9Do75S{(
sSiteURL= sURL; $^fF}y6N
sFilePath = sPath; 1TQ?Fxj
sFileName = sName; Xq$-&~
this.nSplitter = nSpiltter; @!")shc
4JK6<Pk
nCi ]6;Y
} W5Z-s.o
:<P4=P P
GPHb-
public String getSSiteURL() + -Rf@
{ 6HCg<_j]
return sSiteURL; f)_<Ih\/7_
} LKvX~68
@LI;q
m[=SCH-;
public void setSSiteURL(String value) W\>O$IX^e
{ Dh`&B
sSiteURL = value; _5 SvZ;4
} 7310'wc
E9\"@wu[d
:-d#kU
public String getSFilePath() legWY)4D;
{ HjK8y@j
return sFilePath; q+9^rQ
} 8)8~c@
y0p=E^QM
fC'u-m?!Q'
public void setSFilePath(String value) sX6\AYF1M
{ y<6Sl6l*
sFilePath = value; ^4`x:6m
} p'LLzc##
$EY[CA E
Xi"9y @
public String getSFileName() &qWg$_Yh
{ cV>?*9z0
return sFileName; p|->z
} 6kp)'wz`
:.AC%'S
Y[L,rc/j
public void setSFileName(String value) |5(un#
{ o+hp#e
sFileName = value; !X7z y9
} =k<b* 8
O;4S<N
R^`}DlHX
public int getNSplitter() #"6l+}
{ :i>LESJq
return nSplitter; #tZ!D^GQHq
} 5*2hTM!
?:/J8s [O
]uFJ~:R
public void setNSplitter(int nCount) tiGH#~?
{ |rJN
nSplitter = nCount; o%+w:u.
} gtH^'vFZ
} U $#^ e
2#$7!`6K
*1v3x:pQ'
/* x(u.(:V
**Utility.java -}TP)/!,*
*/ [cDDZ+6
package NetFox; (zsmJe
aW:*!d#
>AV9 K
public class Utility { 3q/"4D
j6^.Q/{^
^kK")+K
public Utility() pWzYC@_W
{ a`yCPnB(
4;~xRg;u&*
ww %c+O/
} br88b`L
:@&e~QP(
//线程睡眠 2A
public static void sleep(int nSecond) @8J*vY =e
{ G?F!Z"S
try{ Ke^/aGi}O
Thread.sleep(nSecond); '2l[~T$*
} "T /$K
catch(Exception e) y+BiaD!U
{ 9*j"@Rm
e.printStackTrace (); " AvEo
} o&q:b9T
} MA tF,
`vt+VUNf
//日志 YH^U"\}i
public static void log(String sMsg) ^Mm%`B7W
{ _Rjbm'kC
System.err.println(sMsg); xM)P=y_!M+
} @&HLm^j2O
y46sL~HRv
"?aE3$/
public static void log(int sMsg) W{JR%Sq$
{ |LIcq0Z
System.err.println(sMsg); umPN=0u6
} nUq@`G
} ii`,cJl
'O~_g5kC
De$Ic"Z9L
/* MIr[_
**TestMethod.java Xl$r720ZJr
*/ E\4ZUGy0
package NetFox; ~]%re9jGW
rr1,Ijh{D
F'<XB~&o
public class TestMethod { 7zQGuGo(
l66 QgPA
/FTP8XHwL)
public TestMethod() (Ms #)E
{ ///xx/weblogic60b2_win.exe ?aaYka]
try{ ]S(nA!]
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); hHEn
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); l;z+E_sQ
SiteFileFetch fileFetch = new SiteFileFetch(bean); 3KD:JKn^
fileFetch.start(); fCb&$oRr!
} <vg|8-,#m
catch(Exception e){e.printStackTrace ();} Ktuv a3=>N
pTQ7woj}
ak}ke
} F+zHgE
qCk`398W
(Gzq 1+B
public static void main(String[] args) Ey&A\
{ gvjy'Rm
new TestMethod(); >0N$R|B&
} L!5="s[}
} F ww S[3
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