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)); |g> K$m^
} [@#P3g\:>W
for(int i=0;i<nEndPos.length-1;i++) !K'kkn,h
{ :b^tu8E
nEndPos = nStartPos[i+1]; `"I^nD^t>Y
} Cf<i"
nEndPos[nEndPos.length-1] = nFileLength; ~c! XQJ
} p8[Z/]p
} [>;U1Wt
RNcHU
tLS5yT/
//启动子线程 L2P~moVIi
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ED[PP2[/
for(int i=0;i<nStartPos.length;i++) Sq-mH=rs]
{ s=~r. x
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), -nN}8&l
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), s4;SA
nStartPos,nEndPos,i); q3T'rw%Eh
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ?5'UrqYSW
fileSplitterFetch.start(); 1`5d~>fV
} qW][Q%'lt
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), vNd4Fn)H
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); oVb6,Pn
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", ]^VC@$\)+
nEndPos = " + nFileLength); zvdtP'&uj
// fileSplitterFetch[nPos.length-1].start(); a5?Rj~h!<
Pf]6'?kQ
xV~`sqf
//等待子线程结束 ,8c`
//int count = 0; 0#G&8*FMN
//是否结束while循环 MJ8z"SKnV
boolean breakWhile = false; wR@fB
&0K H00l
4B-v\3Ff
while(!bStop) j?g{*M
{ ;wp)E nF
write_nPos(); >7@F4a
Utility.sleep(500); ,X+mXtg.
breakWhile = true; d.% Vm&3
fJd!;ur)0
rQ;m|@
for(int i=0;i<nStartPos.length;i++) cDxjD5E
{ PZf^r
if(!fileSplitterFetch.bDownOver) w \i#
{ 9@Cqg5Kx'
breakWhile = false; -1:yqF.x
break; FoInJ(PDH
} 1}QU\N(t
} oslrv7EK
if(breakWhile) K {!eHTU
break; ?X]7jH<iw;
Av_1cvR:
o\g",O4-
//count++; p(v+j_ak
//if(count>4) ^E{~{
// siteStop(); \H*"UgS
} y%cg
z./u;/:
#Ji&.T^U/
System.err.println("文件下载结束！"); ]{0 2!
} #QXB2x<*
catch(Exception e){e.printStackTrace ();} +K; X$kB
} tegLGp@_
lmp0Ye|
mmu{K$9}I
//获得文件长度 *t3fbD
public long getFileSize() 2J|Wbey
{ _Sosw|A
int nFileLength = -1; P,j)m\|
try{ [L{q
URL url = new URL(siteInfoBean.getSSiteURL()); @2L+"=u#
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); m.&z:`x[
httpConnection.setRequestProperty("User-Agent","NetFox"); 'eLO#1Ipf
U9SByqa1
b_|`jHes
int responseCode=httpConnection.getResponseCode(); >(|T]u](q
if(responseCode>=400) W-<C%9O!
{ mKvk6OC
processErrorCode(responseCode); -Z-|49I/mN
return -2; //-2 represent access is error a^@6hC>sr
} SYw>P1
u1~H1 ]Ii
ss-{l+Z5
String sHeader; "/S-+Ufn
2pQ zT
38tRb"3zP
for(int i=1;;i++) 6*lTur9ni
{ lN<vu#
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); TXv3@/>ZlG
//Utility.log(in.readLine()); E"b+Q
sHeader=httpConnection.getHeaderFieldKey(i); 0%<Fc9#
if(sHeader!=null) Z7V1e<E
{ %S. _3`A
if(sHeader.equals("Content-Length")) <2fZYt vt
{ %{Kp#R5E
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); qdx(wGG
break; .Lr;{B
} 2!QJa=
} ]L"jt8E
else Xat>d>nJ]
break; f0~<qT?:n
} ^|5vmI'E
} h rW
catch(IOException e){e.printStackTrace ();} f1rP+l-C<
catch(Exception e){e.printStackTrace ();} QaH32(iH
5*/~) wN\U
>OgA3)X
Utility.log(nFileLength); F *=>=
7.,C'^ci
wI'T Je,
return nFileLength; Eh^c4x
} -lQ8 &eB
t3}>5cAxy
",k"c}3G
//保存下载信息（文件指针位置） yTm/P!1S
private void write_nPos() 2`9e20
{ 7v]>ID
try{ 5V':3o;D__
output = new DataOutputStream(new FileOutputStream(tmpFile)); h8&VaJ
output.writeInt(nStartPos.length); \uQ yp*P1s
for(int i=0;i<nStartPos.length;i++) xA& tVQ2!
{ 9{RCh9
// output.writeLong(nPos); _ho9}7 >
output.writeLong(fileSplitterFetch.nStartPos); :XC~G&HuF6
output.writeLong(fileSplitterFetch.nEndPos); Cvry8B
} UMILAoR
output.close(); bBk_2lg=4)
} 4@AY~"dq
catch(IOException e){e.printStackTrace ();} i%_W{;e
catch(Exception e){e.printStackTrace ();} pZ,=iqr
} uZL,+Ce|
J: vq)G\F
f~%|Iu1ob
//读取保存的下载信息（文件指针位置） }F!tM"X\
private void read_nPos() *|{1`{8n
{ h6Ovl
try{ 0/5 a3-3{
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); `|)V]<
int nCount = input.readInt(); RZoSP(6
nStartPos = new long[nCount]; (HbA?Aja
nEndPos = new long[nCount]; 9AF%Y:y
for(int i=0;i<nStartPos.length;i++) -N $4\yp
{ :[xFp}w{
nStartPos = input.readLong(); bWWZGl9
nEndPos = input.readLong(); UR?biq
} ;l`us
input.close(); 6Ck 3tCr
} %;/?DQU
catch(IOException e){e.printStackTrace ();} PgIH(
catch(Exception e){e.printStackTrace ();} Iz^h| n
} 6i'GM`>w
o1lhVM`15
Y\75cfD
private void processErrorCode(int nErrorCode) TS4Yzq,f
{ lt08 E2p9
System.err.println("Error Code : " + nErrorCode); 0"}qND
} dyWj+N5(
q>|&u
uaghB,i'n
//停止文件下载 /M!b3bmA
public void siteStop() m&vuBb3
{ RwKnNIp
bStop = true; Cq8.^=}_
for(int i=0;i<nStartPos.length;i++) 8! eYax
fileSplitterFetch.splitterStop(); ^G(U@-0..
=d`w~iC
MTXh-9DA
} ^E~F,]dV=
} rf?%- X(V
//负责部分文件的抓取 T,@s.v
**FileSplitterFetch.java *I]/ [d
*/ +2xgMN6B@
package NetFox; g$f+X~Q
R*0]*\C z
7<GC{/^T
import java.io.*; | KtI:n4d
import java.net.*; IVSOSl|
C(CwsdlP
UOIB}ut V
public class FileSplitterFetch extends Thread { W{Uz#o
qofD@\-
QNbV=*F?
String sURL; //File URL Ls<^z@I
long nStartPos; //File Snippet Start Position \!LIqqX
long nEndPos; //File Snippet End Position /U26IbJ
int nThreadID; //Thread's ID )iX2r{
boolean bDownOver = false; //Downing is over 6}l[%8
boolean bStop = false; //Stop identical s!<RWy+
FileAccessI fileAccessI = null; //File Access interface z@I'Ryalyc
tNoPpIu
CiWz>HWH
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException S^s|/!>
{ \uPyvA=
this.sURL = sURL; *Xcqnu('
this.nStartPos = nStart; W6gI#
this.nEndPos = nEnd; uwl_TDc>%
nThreadID = id; Znw3P|>B
fileAccessI = new FileAccessI(sName,nStartPos);//定位 8+i=u"<
} fHK.q({Qc
&R5zt]4d&
A=W:}szt]
public void run() _mWVZ1P
{ ]*?lgwE
while(nStartPos < nEndPos && !bStop) {x{~%)-
{ 7F2 WmMS
XEegUTs
~+ kfb^<-
try{ 3iM7c.f*/
URL url = new URL(sURL); Vxz`
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); hT`fAn_
httpConnection.setRequestProperty("User-Agent","NetFox"); tm&,u*6$W?
String sProperty = "bytes="+nStartPos+"-"; J6J">
httpConnection.setRequestProperty("RANGE",sProperty); ?wP/l
Utility.log(sProperty); ZyM7)!+kPa
%rlMjF'tG
Ptm=c6H('
InputStream input = httpConnection.getInputStream(); iD*21c<kd
//logResponseHead(httpConnection); N TcojA{V$
\5|MW)x
5Q;Q
byte[] b = new byte[1024]; $J8g)cS
int nRead; / 3eGt7x#
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) GQ(*k)'a
{ \sz*M B
nStartPos += fileAccessI.write(b,0,nRead); C(8VXtx_
//if(nThreadID == 1) .Hnhd/ c
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); d.|*sZ&3p
} dbJ3E)rF
Q.?(h! )9
,eGguNA9
Utility.log("Thread " + nThreadID + " is over!"); e"y-A&|
bDownOver = true; ,wf:Fr
//nPos = fileAccessI.write (b,0,nRead); G2<$to~{
} a,36FF~&
catch(Exception e){e.printStackTrace ();} IaZmN.k*
} L{&>,ww
} AJ+\Qs(0
wBDHhXi0
jG~-V<&
//打印回应的头信息 ebn3r:IU-
public void logResponseHead(HttpURLConnection con) E{0e5.{
{ Qr\eT}
for(int i=1;;i++) +BeA4d8b
{ inY_cn?
String header=con.getHeaderFieldKey(i); 0W0GSDx
if(header!=null) D6~KLSKm
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ;A4qE W
Utility.log(header+" : "+con.getHeaderField(header)); |a#=o}R_
else P3.
break; o}DRp4;Ka
} -AD@wn!wCJ
} uwQgu!|x
qfG:vTm
Nw9@E R
public void splitterStop() |}L=e.
{ L3w.<h
bStop = true; JH| D
} W[I$([
i=L 86Ks
x <a}*8"
} I{Ip
F?$Vx)HI
vf zC2
/* =;+gge!?bB
**FileAccess.java O|S,="h"}
*//文件访问(定位，写) L(bDk'zi
package NetFox; O:sqm n
import java.io.*; ] )iP?2{
>fMzUTJ4
tA^+RO4
public class FileAccessI implements Serializable{ 43E)ltR=]
9Nps<+K
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 1.M<u)1GU
RandomAccessFile oSavedFile; m62Zta
long nPos; 8nng^
=/}Rnl+c
!uit
public FileAccessI() throws IOException 8o[gzW:Q)U
{ "n]x%. *
this("",0); >;XtJJS
} [ :)F-
CuK>1_Dq
T_!F I29
public FileAccessI(String sName,long nPos) throws IOException cHt4L]n8n
{ kQe<a1 8
oSavedFile = new RandomAccessFile(sName,"rw"); ]h~F%
this.nPos = nPos; i9Beap/t$
oSavedFile.seek(nPos); 0J^Z)U>j
} w+"E{#N
w>8HS+
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public synchronized int write(byte[] b,int nStart,int nLen) wm^1Fn--
{ }-sh
int n = -1; SOE-Kio=B
try{ SHs [te[
oSavedFile.write(b,nStart,nLen); Lc?"4
n = nLen; g%tUkM
} z:Tj0<A'
catch(IOException e) 1TX3/]:
{ tH&eKM4G
e.printStackTrace (); tvf5b8(Y-
} ?FNgJx*\S
b1>]?.
S!#5
return n; 4i.&geXA.
} C[<{>fl)
za}Kd^KeB
V)Oot|
} V dvj*I
(&NLLrsio
k~so+k&=b
/* ,tQNL\t
**SiteInfoBean.java Y@:l!4DI
*/ _f8H%Kgk;
package NetFox; MM]0}65KG
M"W#_wY;
50dN~(;p
public class SiteInfoBean { )b (+=
\BH?GMoP
W!T[ ^+
private String sSiteURL; //Site's URL s-5#P,Lw
private String sFilePath; //Saved File's Path r>! @Z2%s
private String sFileName; //Saved File's Name 9(qoME}>=
private int nSplitter; //Count of Splited Downloading File p>kny?AJ
(tq);m&
|=v,^uo
public SiteInfoBean() IJKdVb~
{//nSplitter的缺省值为5 (^W :f{
//default value of nSplitter is 5 ;hODzfNkS
this("","","",5); P`O`MwEAf
} ygV_"=+|N
pGD-K41O]
v(R^LqE
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) f+ZOE?"
{ +zbCYA
sSiteURL= sURL; :R +BC2x
sFilePath = sPath; n7B2rRJH
sFileName = sName; -(e=S^36
this.nSplitter = nSpiltter; ^wc:qll
@=Pc{xp
>r C*.
} 6W
so1
sN-u?EiF8
public String getSSiteURL() KPDJ$,:
{ V1Ojr~iM
return sSiteURL; w8~R=k
} (=WbLNBS
olr#3te
N.+A-[7,W
public void setSSiteURL(String value) 5#x[rr{^*
{ 9>0OpgvC(
sSiteURL = value; nu:l;+,VY
} cUP1Uolvn
h5T~dGRlR
Yc?S<
public String getSFilePath() j~S=kYrGM
{ g"Hl 30o
return sFilePath; 3?<A]"X.
} 1c@S[y
h4itXJy52B
5(\/ b<#
public void setSFilePath(String value) 'AWWdz
{ zt9A-% \R
sFilePath = value; 9=6BQ`u
} UroC8Tm
2"|7 YI
t'J4zV
public String getSFileName() 82+2PE{
{ 'LuxF1>
return sFileName; _a9oHg
} %-$ :/N
nv+miyvvm
9@lG{9id?
public void setSFileName(String value) 4`9ROC
{ As5l36
sFileName = value; M6quPj
} I(kEvfxc"
u\iKdL
oxeIh9 E
public int getNSplitter() gBWr)R
{ =Ez@kTvOs
return nSplitter; ^~TE$i<
} ar 7.O;e
kREFh4QO,
\(=xc2
public void setNSplitter(int nCount) v9,cL.0&
{ |;(P+Q4lB
nSplitter = nCount; 9ghUiBPiL:
} A /c
} /E{tNd^S
q9VBK(,X
@*L-lx
/* i"Hc(lg
**Utility.java A7XA?>~+|
*/ A.7lo
package NetFox; 5]CaWFSmT
3LJ\y
=_3rc\0
public class Utility { Eb6cL`#N
&}C-W* f,Z
$%ND5uK
public Utility() yKK9b
{ @].!}tz
\kY:|T
z{PPPFk4J
} *81/q8Az
#PPHxh*S
//线程睡眠 *wX[zO+o
public static void sleep(int nSecond) [AIqKyIr
{ 9m_~Zs}Z
try{ nQ|($V1?W
Thread.sleep(nSecond); Y`$\o
} LfU? 1:Du
catch(Exception e) xe(7q1
{ g2^{+,/^K
e.printStackTrace (); v@2@9/
} 2!CL8hG5:
} @}waZ?'
+>2.O2)%q
//日志 </5
public static void log(String sMsg) wL]#]DiE
{ ob9od5Rf
System.err.println(sMsg); 7F]Hq
} E+e),qsbO
/zQx}U)TP
lfd-!(tXD
public static void log(int sMsg) JV4fL~
{ #h9Gl@|
System.err.println(sMsg); t;PG
} U7g,@/Qx
} &w`Ho)P
(Uu5$q(
.V}bfd[k$
/* =;Co0Q`
**TestMethod.java XhWo~zh"
*/ lk81IhI
package NetFox; \Nf[8n#{
r58<A'#
3m-g-
public class TestMethod { {%P2.:
pXBh^
agruS'c g
public TestMethod() qkp0'f*}
{ ///xx/weblogic60b2_win.exe $T66%wX
try{ o /1+ }f
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); TXV^f*
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); aMkuyqPf{
SiteFileFetch fileFetch = new SiteFileFetch(bean); ySDo(EI4
fileFetch.start(); N'l2$8
} 7)2Q
catch(Exception e){e.printStackTrace ();} Rg46V-"d,@
Ly2!(,FB.
]BRwJ2< x
} :9x]5;ma
i-p,x0th
f w)tWJVD
public static void main(String[] args) ]c|JxgU
{ @8aV*zjB
new TestMethod(); 7i02M~*uS
} q|s:&&Wf
} ` l'QAIo
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