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)); Mp|Jt
} cE 'LE1DK
for(int i=0;i<nEndPos.length-1;i++) <Q9l'u]3$c
{ _90D4kGU
nEndPos = nStartPos[i+1]; ?`Yu~a{
} W{"sB:E
nEndPos[nEndPos.length-1] = nFileLength; ?I[8rzBWU
} lTMY|{9
} s"`~Xnf
m.m6.
:&vX0 Ce:
//启动子线程 ?IHt T3'Rt
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 0@-4.IHl
for(int i=0;i<nStartPos.length;i++) FDLo|aP/v
{ 6-_g1vq
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), zY_J7,0g
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), *O~y6|U?
nStartPos,nEndPos,i); `5Kg[nB:
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); s;OGb{H7
fileSplitterFetch.start(); L?d?O
} }h45j84)
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), <WZ{<'ajI
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ?Te#lp;`~
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 8Re[]bE
nEndPos = " + nFileLength); /GO-
// fileSplitterFetch[nPos.length-1].start(); F%|P#CaB
W-s6+DY
N<rq}^qo
//等待子线程结束 lfHN_fE>Mq
//int count = 0; HfVHjF)
//是否结束while循环 ?uSoJM`wa!
boolean breakWhile = false; FAdTm#tgW]
. fja;aG
wBXa;.
while(!bStop) M\m:H3[
{ `CS\"|z
write_nPos(); FE!jN-#
Utility.sleep(500); Ur xiaE
breakWhile = true; ;m7G8)I
TUnAsE/J&
'cpm 4mT
for(int i=0;i<nStartPos.length;i++) w<`0D)mQ
{ I2$DlEke
if(!fileSplitterFetch.bDownOver) \ T#|<=
{ dXh[Ea^
breakWhile = false; aKriO
break; }g/u.@E
} 4)w,gp
} Z|n|gxe
if(breakWhile) {O2=K#J
break; +s}&'V^
q!:dZES
[n[dr@J7v
//count++; R BHDfm'~7
//if(count>4) P!+Gwm{
// siteStop(); z;1dMQ,#
} T$D(Y`zdn
hE {";/}J
QGuqV8 y0
System.err.println("文件下载结束！"); "Wg,]$IvU
} :1*E5pX0n
catch(Exception e){e.printStackTrace ();} %jjPs.
} -orRmn6}
%@vF%
2X\Pw
//获得文件长度 -H6[{WVW!
public long getFileSize() m~ ah!QM
{ bHG<B
int nFileLength = -1; v-z%3x.f
try{ Ih:Q}V#6
URL url = new URL(siteInfoBean.getSSiteURL()); dzOco)y
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); kku<0<(N
httpConnection.setRequestProperty("User-Agent","NetFox"); gvR]"h
6NX#=A
H}kZ;8
int responseCode=httpConnection.getResponseCode(); C~pas~
if(responseCode>=400) Wm6qy6HR
{ d78 [(;
processErrorCode(responseCode); @6'~RD.
return -2; //-2 represent access is error VG 5*17nf5
} rgVRF44X{
P$U"y/
H\QkU`b
String sHeader; W\zZ&*8$
J~5V7B
S9l,P-X`
for(int i=1;;i++) 0vjCSU-X
{ <rE>?zvm
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); j$q5m 24L
//Utility.log(in.readLine()); ~wDXjn"U&
sHeader=httpConnection.getHeaderFieldKey(i); I0zx'x)F
if(sHeader!=null) qqw P4ceG
{ ,kJ7c;:i
if(sHeader.equals("Content-Length")) >O\+9T@
{ +u Iq]tqe
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); kC.!cPd
break; FB?~:7+'
} =Mx"+/Yo*
} 5c]:/9&
else 1@p,
break; $b|LZE\bU.
} + kMj|()>\
} :u,.(INB
catch(IOException e){e.printStackTrace ();} D:Q#%wJ
catch(Exception e){e.printStackTrace ();} 8Ij<t{Lps
QZ&(e2z
7_2D4CI
Utility.log(nFileLength); sg7h&<Xx
CnB[ImMs(A
h}@wPP{
return nFileLength; YjDQ`f/
} gFp3=s0~
{ze69 h
a5#G48'X
//保存下载信息（文件指针位置） hP+4{F*}-
private void write_nPos() lq:q0>vyI
{ jM$bWtq2
try{ qt@/
output = new DataOutputStream(new FileOutputStream(tmpFile)); +4%~.,<_to
output.writeInt(nStartPos.length); Cy?]o?_?
for(int i=0;i<nStartPos.length;i++) 1]:,Xa+|S
{ {KHI(*r;
// output.writeLong(nPos); [gBf1,bK
output.writeLong(fileSplitterFetch.nStartPos); 2%WeB/)9
output.writeLong(fileSplitterFetch.nEndPos); DKt98;
} C<J*C0vQO
output.close(); 8S#$'2sT
} yDqwz[v b
catch(IOException e){e.printStackTrace ();} iKaX8c,zI
catch(Exception e){e.printStackTrace ();} 8s6[-F5
} "?zWCH
zjr($?
eV*QUjS~
//读取保存的下载信息（文件指针位置） rtS cQ
private void read_nPos() 67rY+u%
{ )<V!lsUx'-
try{ &Gh,ROo4
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); mj'~-$5T
int nCount = input.readInt(); 5&s6(?,Eu
nStartPos = new long[nCount]; 9Do75S{(
nEndPos = new long[nCount]; $^fF}y6N
for(int i=0;i<nStartPos.length;i++) 1TQ?Fxj
{ Xq$-&~
nStartPos = input.readLong(); @!")shc
nEndPos = input.readLong(); 4JK6<Pk
} nCi ]6;Y
input.close(); W5Z-s.o
} :<P4=P P
catch(IOException e){e.printStackTrace ();} GPHb-
catch(Exception e){e.printStackTrace ();} + -Rf@
} 6HCg<_j]
q#3T L<
%J1'>nI!q
private void processErrorCode(int nErrorCode) # QwX|x{
{ 6c]4(%8
System.err.println("Error Code : " + nErrorCode); @;eH~3P
} 6 EqN>.
3yRvs;nWS
B7uK:J:c*H
//停止文件下载 ]z'L1vQl7
public void siteStop() \L(jNN0_R
{ bWA_a]G
bStop = true; T@ESMPeU:X
for(int i=0;i<nStartPos.length;i++) k4$zM/ob
fileSplitterFetch.splitterStop(); 7Y@]o=DIc
iqR6z\p&
FBl,Mky
} W\Pd:t
} IB# ua:
//负责部分文件的抓取 "m^gCN}c
**FileSplitterFetch.java qe&|6M!
*/ '|]}f}Go
package NetFox; M%_*vD
!f(A9V
7kV$O(4
import java.io.*; oA5Qk3b:
import java.net.*; 5b rM..
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OF<:BaRs/
public class FileSplitterFetch extends Thread { d"n>Q Tn\
PV,Z@qm@^
0E#??gN
String sURL; //File URL BaIpX<$T
long nStartPos; //File Snippet Start Position E&J<qTH9
long nEndPos; //File Snippet End Position G)~>d/
int nThreadID; //Thread's ID wm#(\dj
boolean bDownOver = false; //Downing is over 6xx.Z3v
boolean bStop = false; //Stop identical g"sb0d9
FileAccessI fileAccessI = null; //File Access interface T:'<:*pD
1^hG}#6_
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException rr1,Ijh{D
{ F'<XB~&o
this.sURL = sURL; }}Q h_(
this.nStartPos = nStart; _JpTHpqu
this.nEndPos = nEnd; NB3+kf,
nThreadID = id; \K2S.j
fileAccessI = new FileAccessI(sName,nStartPos);//定位 'yOx&~H]
} }rVLWt
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qzY:>>d'
public void run() 3 P\4K
{ sFfargl
while(nStartPos < nEndPos && !bStop) sWA-_4
{ jbOwpyH
V:D?i#%,z
,!AYeVq
try{ 5#_GuL%
URL url = new URL(sURL); V+'zuX
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !Y^B{bh
httpConnection.setRequestProperty("User-Agent","NetFox"); bneP>Bd
String sProperty = "bytes="+nStartPos+"-"; A{{rNbCK
httpConnection.setRequestProperty("RANGE",sProperty); Z~ q="CA4
Utility.log(sProperty); 0n{+_
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S2I{?y&K
InputStream input = httpConnection.getInputStream(); >r:z`^p
//logResponseHead(httpConnection); 4[r:DM|8
bA"*^"^
7'.6/U
byte[] b = new byte[1024]; #)DDQ?D
int nRead; A9HgABhax
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) (ia+N/$u
{ eZpi+BRS6
nStartPos += fileAccessI.write(b,0,nRead); 0*OK]`9
//if(nThreadID == 1) 1- GtZ2
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); $KRpu<5i}
} YTe8C9eO
mk-L3H1@J3
tpV61L
Utility.log("Thread " + nThreadID + " is over!"); @!\lt$
bDownOver = true; ewYk>
//nPos = fileAccessI.write (b,0,nRead); KmF+3g~#s
} k V'0rb
catch(Exception e){e.printStackTrace ();} z\J#d 1e
} 8 =3#S'n
} A{hST~s
OYfP!,+bn
ui*CA^ Y
//打印回应的头信息 Ag]Hk%
public void logResponseHead(HttpURLConnection con) q>a/',m
{ hG/Z65`&
for(int i=1;;i++) "Bn]-o|r
{ vdulrnGqL
String header=con.getHeaderFieldKey(i); [+dTd2uZ<\
if(header!=null) y5V]uQSD
//responseHeaders.put(header,httpConnection.getHeaderField(header)); oH [-fF
Utility.log(header+" : "+con.getHeaderField(header)); g;nPF*(
else wqn}t]
break; wGpw+O
} y?s#pSX;N
} wdgC{WGl
aj]%c_])(
4d]T`
public void splitterStop() {uO2m*JrI
{ }~Y#N
bStop = true; 0c:jwtf
} 7[7Sm^Tw
WkY>--^
[~rBnzb
} j0K}nS\ P
~Ywto
jDM^e4U.l
/* <+7-^o_
**FileAccess.java z9*7fT
*//文件访问(定位，写) JMYM}G
package NetFox; cM+s)4TPL
import java.io.*; d,).O
T EqCoeR
\CE8S+Z%
public class FileAccessI implements Serializable{ <j89HtCz
uw&'=G6v
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 @MGc_"b
RandomAccessFile oSavedFile; g~=#8nJ
long nPos; I'RhA\`
@Nt$B'+S&
R*psL&N
public FileAccessI() throws IOException -Z%B9ql'
{ 9/S-=VOe.t
this("",0); U_c9T>=
} ur`:wR] 2?
2f@gR9T
JS1''^G&.
public FileAccessI(String sName,long nPos) throws IOException HveOG$pT
{ zpd Z.
oSavedFile = new RandomAccessFile(sName,"rw"); KrT+Svm
this.nPos = nPos; U ()36
oSavedFile.seek(nPos); cw{[% 7
} 6~0.YZ9
My!<_Hp-W
Z:}d\~`x$%
public synchronized int write(byte[] b,int nStart,int nLen) "#mr?h_
{ p} }=li>
int n = -1; 6<<ihm+
try{ JB= L\E}
oSavedFile.write(b,nStart,nLen); u=h/l!lR
n = nLen; 7*r7Q'
} $n?@zd@53
catch(IOException e) ,;yiV<AD
{ ]\<^rEU
e.printStackTrace (); ?-0>Wbg
} @dCoh-Q3
@'EU\Y\l
n +z5;'my
return n; J0M7f]
} *:3`$`\54
( XoL,lJ
Ju#t^P
} H:BWv08~5
xW\iME
u%vq<|~-
/* LCRZ<?O[|
**SiteInfoBean.java {?' DZR s
*/ 2!b+}+:
package NetFox; -HU5E>xG
Pp[?E.]P
fWywegh
public class SiteInfoBean { 0x\bDWZ_
gUB%6vG\I
-&* 4~
private String sSiteURL; //Site's URL SablF2doa
private String sFilePath; //Saved File's Path BVX6
private String sFileName; //Saved File's Name &i,xod6$
private int nSplitter; //Count of Splited Downloading File gzthM8A
?HBNd&gZ1G
0;j)rmt
public SiteInfoBean() ?E0j)P/ (
{//nSplitter的缺省值为5 Mg0[PbS
//default value of nSplitter is 5 *94<rlh{"
this("","","",5); #B3P3\
} Eh)PZvH
|Psi?'4
h7|#7 d
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) r9Wk7?w)
{ O$ 7R<V
sSiteURL= sURL; [;/ydE=
sFilePath = sPath; {f\/2k3
sFileName = sName; kqfO3{-;{:
this.nSplitter = nSpiltter; [wJM=`!W
MV<2x7S
1>1&NQ#}
} Ap{p_~~iJ
a'zf8id
=Vv"\p8
public String getSSiteURL() >M\3tB2C
{ E {$Jk]c
return sSiteURL; i"~J -{d}
} ]CD
FabzP_<b
+pcpb)VL
public void setSSiteURL(String value) =1noT)gCR
{ j>(O1z7
sSiteURL = value; ) N*,cTE
} 0L_JP9e
W *t+!cU/:
[;`B
public String getSFilePath() TzT(aWP"
{ v"VpE`z1#
return sFilePath; }j^asuf~c
} ?CgqHmf\\(
'`#sOH
I'Dc9&2
public void setSFilePath(String value) fD<9k
{ Fy^=LrH=D
sFilePath = value; LE!xj 0
} Tji G!W8
qU(,q/l
$[L~X M
public String getSFileName() ALVHKL2
{ b!C\J
return sFileName; K!c "g,S
} |'B-^?;
hSQuML
mhZ{}~
public void setSFileName(String value) Ib(q9!L
{ +>b~nK>M
sFileName = value; &DQyJJ`k
} .v?x>iV
\wR $_X&
!2-f%x]tO
public int getNSplitter() _?"P<3/iF
{ @N,(82k
return nSplitter; .gL%0
} z ;>xI~
hXBAs*4DV8
>/@wht4- j
public void setNSplitter(int nCount) iI|mFc|V
{ @]v}&j7
nSplitter = nCount; (gY3?&Ok*
} eD4D<\*
} 3 q1LIM
6'YT3=
cR'l\iv+
/* e :(7$jo
**Utility.java w;@NYMK)
*/ cEI "
package NetFox; (_h=|VjK(I
5bKBVkJ'
wKxw|Fpn
public class Utility { a8D7n Ea
:w|ef;
[Dr'
public Utility() BvQMq5&
{ 1b^e4
rC`pTN
05o)Q &`
} :G3PdQb^
BC:d@
//线程睡眠 sIUhk7Cd8
public static void sleep(int nSecond) eh\_;2P
{ S#h-X(4
try{ ~ _ ogeD
Thread.sleep(nSecond); 2/XrorV
} 5`Q*
catch(Exception e) kYbqb?
{ ~quof>
e.printStackTrace (); 'q3<R%^Q
} _C`&(?}
} z$64Ep#
+D7>$&BD
//日志 kq| r6uE
public static void log(String sMsg) Q]/ZVcoqo
{ w)C/EHF
System.err.println(sMsg); bwrM%BL
} #)}K,FDd
!wbO:py[8>
O*Gg57a
public static void log(int sMsg) O`?qnNmc;
{ (,nQ7,2EX
System.err.println(sMsg); k4N_Pa$}\
} k^VL{z:EWB
} Q$Q>pV;uH
`$PdI4~J
]rNM3@bVy
/* >m:;.vVY
**TestMethod.java Nxm^jPM0
*/ xDqJsp=]-
package NetFox; M `O=rH }
qLjLfJJ2
u-s*3Lg&
public class TestMethod { s9#WkDR
PHAM(iC&D
Dj9v9
public TestMethod() D02'P{
{ ///xx/weblogic60b2_win.exe #%9t-
try{ 9%#u,I
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Rb/|ae
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ZVX1@p
SiteFileFetch fileFetch = new SiteFileFetch(bean); B4 k5IS
fileFetch.start(); 6o:b(v&Oo
} $?Km3N\?v
catch(Exception e){e.printStackTrace ();} fA$2jbGW
B~?R 6
h5)4Z^n
} a!@(bb z>
| )No4fm
=I.uf
public static void main(String[] args) =67ab_V
{ ,kQCCn]
new TestMethod(); I]@QhCm0
} +X%pUe
} l;;,[xhq
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