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)); &|j^?ro6
} \'}? j-8
for(int i=0;i<nEndPos.length-1;i++) z}sBx9;
{ 3R|C$+Sc
nEndPos = nStartPos[i+1]; A"PmoV?lAm
} !JOM+P:
nEndPos[nEndPos.length-1] = nFileLength; <lxE^M
} p0b2n a !
} `N,q~@gL
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+:#x!i;W8[
//启动子线程 Jd0I!L
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; pZA0Go2!IN
for(int i=0;i<nStartPos.length;i++) .V.x0
{ \A'tV/YAd
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), N7WQ{/PSG
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 9}_ccq
nStartPos,nEndPos,i); }vGWlNd#g
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); j1Q"s(
fileSplitterFetch.start(); FLE2]cL-
} ='"hB~[
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), <JyF5
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); <Jwx|
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", @UG%B7
nEndPos = " + nFileLength); ow!NH,'Hy
// fileSplitterFetch[nPos.length-1].start(); /ivA[LSS
k9|8@3(h
BIM!4MHLA
//等待子线程结束 (TjY1,f!H
//int count = 0; {*jo,<4ee
//是否结束while循环 2U Q&n`A
boolean breakWhile = false; d2!A32m
8qi6>}A
F CbU> 1R
while(!bStop) $afE= qC*
{ &0='z
write_nPos(); ~s[St0
Utility.sleep(500); 1m5=Nu
breakWhile = true; ff3HR+%M
?8O %k<?
+"HLx%k
for(int i=0;i<nStartPos.length;i++) A/%+AH(
{ X4bB
if(!fileSplitterFetch.bDownOver) Q-qM"8I
{ F^mMyK
breakWhile = false; `]q>A']Dl
break; !B#Lea
} IB sQaxt.
} 0';U3:=i,
if(breakWhile) -hpJL\ng
break; a1 I"Sh
u*aFWl]=
ha%3%O8Z
//count++; Y@+e)p{
//if(count>4) BJ]4j-^o
// siteStop(); ^zv,VD
} _2wU(XYH
+-VkRr#
SS/9fT"[
System.err.println("文件下载结束！"); +].Zs<
} xP3v65Q1
catch(Exception e){e.printStackTrace ();} $Eo)i
} + \DGS
ZP]l%6\.
~; emUU
//获得文件长度 \R6D'Yt
public long getFileSize() ep<O?7@j-G
{ Yb~[XS |p
int nFileLength = -1; ?_!} lg
try{ #-0}r
URL url = new URL(siteInfoBean.getSSiteURL()); *G<K@k
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); '\&t3?;
httpConnection.setRequestProperty("User-Agent","NetFox"); w=UFj
s Y^#I
\5MW65
int responseCode=httpConnection.getResponseCode(); xUiSAKrcM
if(responseCode>=400) M_5$y)M
{ VdVUYp
processErrorCode(responseCode); E%?X-$a
return -2; //-2 represent access is error K%+[2Hj2
} O,&nCxB]
x8#bd{
SnK#YQCDt
String sHeader; ?gp:uxq,.
"M)kV5v%
ot"3 3I
for(int i=1;;i++) ) r8yt}
{ (iwZs:k-
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); IfK%i/J
//Utility.log(in.readLine()); u~WE}VC
sHeader=httpConnection.getHeaderFieldKey(i); <6 LpsM}
if(sHeader!=null) BrWo/1b
{ 'zEmg}
if(sHeader.equals("Content-Length")) J6WyFtlyLc
{ cv .R`)l
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ^#-i%V%
break; z1-JoZ
} (?G?9M#7_
} %Sgdhgk1
else *J ]2"~_.
break; #J=@} S)
} nB;yS<
} u%o2BLx
catch(IOException e){e.printStackTrace ();} =54"9*
catch(Exception e){e.printStackTrace ();} )A@i2I
_P^ xX'v
dx/NY1
Utility.log(nFileLength); w7(jSPB
I6q]bQ="
<~rf;2LZ
return nFileLength; ._6|epJ#
} 55mDLiA
-Um|:[*I
w9Eb\An
//保存下载信息（文件指针位置） myR}~Cj;q
private void write_nPos() rJ@yOed["b
{ shn{]Y
try{ e>OYJd0s
output = new DataOutputStream(new FileOutputStream(tmpFile)); OdZLJt?g
output.writeInt(nStartPos.length); /]_a\x5Ss
for(int i=0;i<nStartPos.length;i++) q h+c}"4m
{ @CxXkR
// output.writeLong(nPos); 2l8TX#K
output.writeLong(fileSplitterFetch.nStartPos); b<1k$0J6
output.writeLong(fileSplitterFetch.nEndPos); KMhEU**
} )|Ho"VEmg
output.close(); YFGQPg
} N?RJuDW
catch(IOException e){e.printStackTrace ();} Q#,j,h
catch(Exception e){e.printStackTrace ();} "!fvEE
} 6F@2:]W
k~YZT 8
"G(^v?x:P
//读取保存的下载信息（文件指针位置） ThvVLK
private void read_nPos() Q9\6Pn ]T
{ f`[gRcZ-
try{ B?-~f^*,jG
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); x+X^K_*
int nCount = input.readInt(); B!z-O*fLE1
nStartPos = new long[nCount]; +1R qo
nEndPos = new long[nCount]; " iKX-VIl
for(int i=0;i<nStartPos.length;i++) f<Co&^A
{ x c[BQ|P=
nStartPos = input.readLong(); MgP6ki1z
nEndPos = input.readLong(); >_<J=8|E
} UImd*;2TE
input.close(); =$^<@-;
} :J'ibb1
catch(IOException e){e.printStackTrace ();} 9uRs@]i
catch(Exception e){e.printStackTrace ();} Hf ]w
} -%h0`hOG{
}+" N '
.QaHE`e{
private void processErrorCode(int nErrorCode) !OO{qw(*g
{ 9AbSt&#
System.err.println("Error Code : " + nErrorCode); hZudVBn
} VgoN=S
EZz`pE
\k8|3Y~g
//停止文件下载 x;G~c5
public void siteStop() Gz>M`M`[4
{ oI!L2
bStop = true; LvtZZX6!
for(int i=0;i<nStartPos.length;i++) ;M95A
fileSplitterFetch.splitterStop(); H/eyc`
XHN`f#(w
+Yuy%VT
} H"_]Hq
} 77:s=)
//负责部分文件的抓取 T{L{<+9%
**FileSplitterFetch.java CQLh;W`Dc
*/ 1o;*`
package NetFox; F%}0q&
icX$<lD
0Q]p#;
import java.io.*; ~[|zf*ZISG
import java.net.*; NWGSUUa
zeXMi:X
Fe4QWB6\U
public class FileSplitterFetch extends Thread { ${/"u3a_
C&\vVNV;9
6iozb~!Rr
String sURL; //File URL S[J=d%(
long nStartPos; //File Snippet Start Position +dkbt%7M
long nEndPos; //File Snippet End Position *L%i-Wg"
int nThreadID; //Thread's ID \/jr0):
boolean bDownOver = false; //Downing is over 5Wj+ey^^w
boolean bStop = false; //Stop identical \TG!M]D:
FileAccessI fileAccessI = null; //File Access interface l`2X'sw[/
29"eu#-Qj
?Z@FxW
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException /Yk2 |L
{ '0|AtO77
this.sURL = sURL; %/dYSC
this.nStartPos = nStart; NyD[9R?
this.nEndPos = nEnd; i0uBb%GMT
nThreadID = id; \?[#>L4
fileAccessI = new FileAccessI(sName,nStartPos);//定位 %zHNX4
} h<.G^c)
,\;;1Kq
L!E/ )#{
public void run() +dm&XW >
{ c'_-jdi`>_
while(nStartPos < nEndPos && !bStop) %T*lcg
{ d"+zDc;
rt%.IQdY
m?-3j65z
try{ - Z"w
URL url = new URL(sURL); c/ wzV
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); L0SeG:
httpConnection.setRequestProperty("User-Agent","NetFox"); >_U)=q
String sProperty = "bytes="+nStartPos+"-"; /%Bc*k=ox
httpConnection.setRequestProperty("RANGE",sProperty); "U34D1I)#
Utility.log(sProperty); n.C.th >Y1
e*uaxh+7
\)VV6'zih
InputStream input = httpConnection.getInputStream(); m~~_iz_*
//logResponseHead(httpConnection); buGW+TrWY
1TfK"\
p5^,3&
byte[] b = new byte[1024]; ~$>l@> xX
int nRead; k oo`JHC
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) q{ov62t`
{ < vU<:S
nStartPos += fileAccessI.write(b,0,nRead); V\@h<%{^%7
//if(nThreadID == 1) @D8c-`LC"*
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); o)'T#uK
} x^}kG[s
,#&lNQ'I
>z6(fM`i
Utility.log("Thread " + nThreadID + " is over!"); 7]YLe+Ds
bDownOver = true; Eom|*2vWIC
//nPos = fileAccessI.write (b,0,nRead); .ps'{rl8
} ;rpjXP
catch(Exception e){e.printStackTrace ();} pt;E~_
} b9[;qqq@'
} !v^D}P 3Y
8Cz_LyL
+T=Z!2L
//打印回应的头信息 8 s!0Z1Roc
public void logResponseHead(HttpURLConnection con) E\#hcvP
{ LF <fp&C)h
for(int i=1;;i++) aOfL;I
{ T5NO}bz
String header=con.getHeaderFieldKey(i); g5R2a7
if(header!=null) [=9-AG~}
//responseHeaders.put(header,httpConnection.getHeaderField(header)); /ZZo`
Utility.log(header+" : "+con.getHeaderField(header)); j]}A"8=1
else [wP;g'F
break; 2}>jq8Y47
} `h_,I R<
} NY\q
|r1\
vGO-a2Z
public void splitterStop() @Z~lM5n$8
{ -EFtk\/
bStop = true; }rsD$
} q17c)]<"
P%f],f
Oga0CR_
} $[5ihV$u
<i"U%Ds(
,x!P|\w.G{
/* 9kL'"0c
**FileAccess.java /8@JWK^I{
*//文件访问(定位，写) k'}}eu/ q
package NetFox; T[B@7$Dp*
import java.io.*; T j9;".
JLm0[1Lzd
v5i[jM8
public class FileAccessI implements Serializable{ L.>tJ.ID
OaRtGJnR
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 PcC9)x
RandomAccessFile oSavedFile; AJ`b-$Q
long nPos; :XEr{X
=\`g<0
E.Xfb"]
public FileAccessI() throws IOException VS@o_fUx)
{ /=>z|?z3
this("",0); %h 6?/
} 7lY&/-V
HT)b3Ws~M8
&N GYV
public FileAccessI(String sName,long nPos) throws IOException sguE{!BO
{ 2;r(?ebw
oSavedFile = new RandomAccessFile(sName,"rw"); EMzJJe{Cv
this.nPos = nPos; 1U.se`L
oSavedFile.seek(nPos); )(TaVHJR
} ]S<eO6z
frbKi _1
]24aK_Uu
public synchronized int write(byte[] b,int nStart,int nLen) 5t#+UR
{ &G7JGar
int n = -1; "{105&c\
try{ LOpnPH`
oSavedFile.write(b,nStart,nLen); ?Q[uIQ?dV
n = nLen; z8{kwz
} N~_GJw@
catch(IOException e) |8PUmax
{ <KqZ.7XfB
e.printStackTrace (); _HX1E
} `4__X;
~Wjm"|c
wv<D%nF2|
return n; D% }?l
} uFOxb}a9v
/R^Moj<
6js94ko[
} ^5j|
_"SE^_&c
-v.\CtpHv
/* h 1G`z
**SiteInfoBean.java Er^ijh,
*/ L22GOa0
package NetFox; :zdMV6s
!c[(#g
u"XqWLTV
public class SiteInfoBean { 0"7xCx
MO&QR-OY
w~+5FSdH
private String sSiteURL; //Site's URL tp<uN~rTgh
private String sFilePath; //Saved File's Path h 92\1,
private String sFileName; //Saved File's Name u[9i>7}9
private int nSplitter; //Count of Splited Downloading File l_GvdD
VXXo\LQUU
@-nCK Yj
public SiteInfoBean() &M(=#pq9
{//nSplitter的缺省值为5 :L#t?~
//default value of nSplitter is 5 #D M%_HXDi
this("","","",5); cZI )lX
} gQ4Q h;
S%gb1's
u,e'5,`N
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) a)=WDRk
{ \PU3{_G]
sSiteURL= sURL; &QO~p3M
sFilePath = sPath; u}Vc2a,WV
sFileName = sName; FJKW=1=,
this.nSplitter = nSpiltter; O4@sN=o
$~vy,^
HSGM&!5mW
} R2WEPMH%
zJJ KLr;
Bf!i(gM
public String getSSiteURL() #A<|&#hh
{ <Z5ak4P
return sSiteURL; Q<W9<&VZe
} m<)0XE6w
H|_^T.n?E
{;0j9rr
public void setSSiteURL(String value) +;~JHx.~X
{ `3+yu' Q'
sSiteURL = value; U]j4Izq
} S6-)N(3|
1];rW`Bw
54~`8f
public String getSFilePath() 2GOQ|Z
{ g+Vfd(e
return sFilePath; #PUvrA2Zl
} pFi.?|6"
V\^rs41$;
0STtwfTr:
public void setSFilePath(String value) 3Tze`Q 9
{ !GI*R2<W
sFilePath = value; #g[jwl'
} bOjvrg;Sz\
Q4e*Z9YJ
N:'v^0
public String getSFileName() fkE4[X7f
{ ^$qr6+
return sFileName; v#*9rNEj0
} H~%HTl
<>/0;J1<
jL8[;*^G
public void setSFileName(String value) 2[f8"'lUQ
{ xCwd*lsM
sFileName = value; [of{~
} 0<*R 0
xc)A`(g
`tA~"J$32l
public int getNSplitter() O\y#|=d
{ ,l`4)@{G
return nSplitter; 19-|.9m(
} @wO"?w(
k(1]!c4J0
QX}O{LQR
public void setNSplitter(int nCount) 8CKN^8E
{ OZ 4uk.)
nSplitter = nCount; lc1?Vd$
} =4`#OQ&g
} {n9]ej^
!f5I.r~
<)n8lIK
/* 2eErvfC[
**Utility.java ]q@/:I9]
*/ ,)%al76E
package NetFox; CVfQ
RbB y8ZVM
d]Y-^&]{]
public class Utility { I3Gz,y+
<=WSX{_D
(iM*Y"Y
public Utility() ioxsx>e<
{ <aps)vF
1.\|,$
=7%1]
} j8/rd
On%21L;JG
//线程睡眠 hE.NW
public static void sleep(int nSecond) I|jGu9G
{ l)y$c}U
try{ +$Q.N{LV
Thread.sleep(nSecond); CZ2&9Vb9I
} i,HafY
catch(Exception e) 951"0S`Lo
{ W vh3Y,|3
e.printStackTrace (); N7%iz+
} ul0]\(sS:
} Vgy}0pCl
E.*TJ
//日志 bvyX(^I[q
public static void log(String sMsg) r9!jIkILz
{ GilaON*pK.
System.err.println(sMsg); @C[]o.r
} j2GO ZKy
pfd||Z
ZJUTtiD
public static void log(int sMsg) Pl|e?Np
{ OVr, {[r
System.err.println(sMsg); Nb.AsIR^
} z"4UObVs
} Q-<,+[/
0*?/s\>PS;
4 ZD~i e
/* _-^bAr`z
**TestMethod.java /?<tjK' "H
*/ C@!C='b,
package NetFox; [x}]sT`#a
P'Q|0lB
h\+U+?u
public class TestMethod { |e+8Xz1>
kpc3l[.A
63hOK
public TestMethod() g3B zi6$m
{ ///xx/weblogic60b2_win.exe sW/^82(dM
try{ sTu6KMn
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); F8e]sa$K\
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 5|l&` fv`
SiteFileFetch fileFetch = new SiteFileFetch(bean); i <KWFF#
fileFetch.start(); *=]hc@
} Yh`P+L
catch(Exception e){e.printStackTrace ();} *5( h,s3&
T&.ZeB1
J%|!KQl
} QR'yZ45n4
i:ar{ q
]y*AA58;
public static void main(String[] args) |eD$eZ=m
{ D&5>Op4U
new TestMethod(); HKA7|z9{
} anwMG0
} #{973~uj
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