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)); ]~$@x=p2e
} 1 39T*0C
for(int i=0;i<nEndPos.length-1;i++) k]gPMhe
{ p".wqg*W
nEndPos = nStartPos[i+1]; q%k&O9C2]
} ;*K;)C
nEndPos[nEndPos.length-1] = nFileLength; XU<owk
} h('5x,G%
} 1LFad>`
'H`:c+KDG`
w9u|E46
//启动子线程 `tO t+>YWn
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; @lM-+q(tl
for(int i=0;i<nStartPos.length;i++) B]hRYU
{ r]}6iF.
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 3 u=\d)eq
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ~%tVb c
nStartPos,nEndPos,i); g_PP9S_?
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); o S{hv:)>
fileSplitterFetch.start(); gs0jwI
} 1Cc91
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), /xSJljexz
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); #N`MzmwS
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", zGme}z;1@
nEndPos = " + nFileLength); nT4Ryld
// fileSplitterFetch[nPos.length-1].start(); i.K!;E>
r25VcY
LIJ#nb
//等待子线程结束 !iHC++D
//int count = 0; NG\'Ii:-J
//是否结束while循环 N?S;v&q+
boolean breakWhile = false; 'G[G;?F
l`6.(6
5`}za-
while(!bStop) &RuTq6)r
{ $uwz`N:
write_nPos(); ,|8aDL?
Utility.sleep(500); e7n0=U0
breakWhile = true; TSJeS`I
sJQ~:p0e
UZ<.R"aK
for(int i=0;i<nStartPos.length;i++) TXd6o=
{ #CJET
if(!fileSplitterFetch.bDownOver) ?|oN}y"i
{ pi70^`@'B
breakWhile = false; [Djx@x
break; L|D9+u L
} npytb*[|c
} : maBec)
if(breakWhile) n<)A5UB5-
break; 39[ylR|\
9%R"(X)
nT~XctwF
//count++; MdEds|D
//if(count>4) A3HNMz
// siteStop(); j,%i.[8S
} U7fNA7#x"
O\oRM2^u}
dA2@PKK
System.err.println("文件下载结束！"); Gys-Im6>~@
} XdzC/{G
catch(Exception e){e.printStackTrace ();} ;X+.Ag
} G.N`
f `b6E J
iz[IK%K
//获得文件长度 |"b|Q
public long getFileSize() Dbx zqd
{ n0K+/}m
int nFileLength = -1; J_XkQR[Y
try{ 1NTx?JJfW
URL url = new URL(siteInfoBean.getSSiteURL()); rHybP6C<
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 03iy[~Y2
httpConnection.setRequestProperty("User-Agent","NetFox"); PktnjdFV
~ e<,GUx(]
V3|" v4
int responseCode=httpConnection.getResponseCode(); 5&A' +]
if(responseCode>=400) T1?9E{bC8A
{ xIb{*)BUwc
processErrorCode(responseCode); xVI"sBUu
return -2; //-2 represent access is error .;U?%t_7
} cJSwA&
lR F5/
+wHa)A0MW
String sHeader; *Br }U
{ /8s`m
'm<L}d
for(int i=1;;i++) VD!PF'
{ EronNtu8i
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); X=Y(,ZR(&
//Utility.log(in.readLine()); 5>H&0> \
sHeader=httpConnection.getHeaderFieldKey(i); ::GW
if(sHeader!=null) -IDhK}C&T
{ FyXO @yF
if(sHeader.equals("Content-Length")) 0>;[EFL
{ TgLr4Ex
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ?!c7Zx,(
break; o5+7Lt]
} $QT% -9&
} z)eNM}cF
else %3=T7j
break; n~jW
} D4@(_6^
} Du-Q~I6
catch(IOException e){e.printStackTrace ();} _S*QIbO
catch(Exception e){e.printStackTrace ();} hr&UD|E=
"cOBEhn%l
m<;MOS
Utility.log(nFileLength); ulEtZ#O{_
3+C;zDKa
5YUe>P D
return nFileLength; Mx3fT>?
} U`{ M1@$
!af;5F
{)kL7>u]^V
//保存下载信息（文件指针位置） wXYT(R
private void write_nPos() Ir- 1@_1Q
{ sP9{tk2K
try{ .7Pp'-hK
output = new DataOutputStream(new FileOutputStream(tmpFile)); iP9Dr<P
output.writeInt(nStartPos.length); Y{t}sO%A
for(int i=0;i<nStartPos.length;i++) Xz/aytp~A
{ R$it`0D4o
// output.writeLong(nPos); t`Xx\
output.writeLong(fileSplitterFetch.nStartPos); ,d HAD
output.writeLong(fileSplitterFetch.nEndPos); "HJQAy?W
} 0G'v4Vj0'
output.close(); sAK&^g
} ZY6%%7?1
catch(IOException e){e.printStackTrace ();} SM<qb0
catch(Exception e){e.printStackTrace ();} ;ae6h [
} ep l1xfr
O "Aeg|
S4E@wLi
//读取保存的下载信息（文件指针位置） @}%kSn5y:
private void read_nPos() Idj Z2)$
{ D [v225
try{ mndEB!b
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); JvJ)}d$,&
int nCount = input.readInt(); YR)^F|G
nStartPos = new long[nCount]; ILHn~d IC
nEndPos = new long[nCount]; l`:-B'WM
for(int i=0;i<nStartPos.length;i++) An BM*5G
{ F=UW[zy/[
nStartPos = input.readLong(); COH.`Tv{*
nEndPos = input.readLong(); #S|On[Q!
} h`tf!MD]
input.close(); g)<[-Q1
} /pGx!
catch(IOException e){e.printStackTrace ();} 1"1ElH
catch(Exception e){e.printStackTrace ();} TP`"x}ACa?
} K$$%j"s
j{m{hVa
PhmtCp0-7-
private void processErrorCode(int nErrorCode) m .En!~t
{ tU8aPiUl
System.err.println("Error Code : " + nErrorCode); (d[JMO^@8
} E/d\ebX|
Hjy4tA7,l
fKs3H?|
//停止文件下载 CZCVC (/u
public void siteStop() 2\Yv;J+;
{ |fn%!d`2
bStop = true; /DSy/p0%
for(int i=0;i<nStartPos.length;i++) RS7J~Q
fileSplitterFetch.splitterStop(); Vl:M6d1
(g tOYEqx
<.@w%rvG
} Sh<A936/E
} 'f.5hX(Y
//负责部分文件的抓取 H_%ae'W
**FileSplitterFetch.java fa/p
*/ 2bpFQ8q
package NetFox; uVw|jj
S.owVMQ
"W"r0"4
import java.io.*; "N=q>jaX
import java.net.*; tqU8>d0^
z)*\njYe
ZB,UQ~!Yr
public class FileSplitterFetch extends Thread { KeC&a=HL
c+<gc:#jy
tQ2S*]"f
String sURL; //File URL W6yz/{Rf
long nStartPos; //File Snippet Start Position u z:@
long nEndPos; //File Snippet End Position )Mw 3ZE92
int nThreadID; //Thread's ID 7$:Jea
boolean bDownOver = false; //Downing is over mZ#IP
boolean bStop = false; //Stop identical 8w3Wy<}y
FileAccessI fileAccessI = null; //File Access interface T(*A0
j<vU[J+gx~
>DR/lBtL
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException GS!1K(7
{ mgBxcmv
this.sURL = sURL; 0MOn>76$N
this.nStartPos = nStart; 9sB LCZ
this.nEndPos = nEnd; S^@#%>
nThreadID = id; [\"<=lb`
fileAccessI = new FileAccessI(sName,nStartPos);//定位 sO&eV68 [
} X*M--*0q'
j1dz'G}hj
/^[K
public void run() fR lJ`\ t
{ v/G^yZa
while(nStartPos < nEndPos && !bStop) ??Dv\yLZI
{ *18J$
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)B Xl|V,
try{ 5R#:ALwX:
URL url = new URL(sURL); Q".p5(<
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 'i8?]` T
httpConnection.setRequestProperty("User-Agent","NetFox"); 4"V6k4i5
String sProperty = "bytes="+nStartPos+"-"; J2$=H1-
httpConnection.setRequestProperty("RANGE",sProperty); I,?!NzB
Utility.log(sProperty); 1++Fs
d|$-Sz
O}[){*GG=
InputStream input = httpConnection.getInputStream(); <Ow+LJWQK
//logResponseHead(httpConnection); hhr>nuA
g7]g0*gxXW
8"x\kSMb
byte[] b = new byte[1024]; -"n8Wv
int nRead; Z ,98
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) -.7UpDg~
{ (7}Zh|@W
nStartPos += fileAccessI.write(b,0,nRead); 5ZHO+@HiFH
//if(nThreadID == 1) Z4PAdT
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); D?9EO=
} unkA%x{W;
.+CMm5T
lKy4Nry9
Utility.log("Thread " + nThreadID + " is over!"); [{rne2sA
bDownOver = true; U,^jN|v
//nPos = fileAccessI.write (b,0,nRead); wEbO|S+K1
} _K|?;j#x0k
catch(Exception e){e.printStackTrace ();} ut9R]01:
} qyYf&VC}
} vjXCArS
Y@V6/D} 1
C~VyM1inD
//打印回应的头信息 b]5S9^=LI
public void logResponseHead(HttpURLConnection con) 2dBjc{
{ U\",!S~<
for(int i=1;;i++) |#(g8ua7
{ M9sB2Ips<
String header=con.getHeaderFieldKey(i); m}fY5r<<;/
if(header!=null) #h7$b@
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 'd|E>8fejG
Utility.log(header+" : "+con.getHeaderField(header)); 7:h_U9Za?$
else ?nx 1{2[
break; J~rjI24
} #+PfrS=
} 82Nw6om6i
.1?7)k v
`v$Bib)
public void splitterStop() 3 p9LVa
{ I}7=\S/@
bStop = true; rZ7)sE5L
} ?anKSGfj
),+u>Os&
I'16-
} e!*%U=[Q
u:O6MO9^
jj"?#`cW
/* E 5bo60z
**FileAccess.java Z~Z+Yt;,9a
*//文件访问(定位，写) Rk52K*Dc
package NetFox; ,V:RE y
import java.io.*; TGQDt|+Z
;Ajy54}7
O\qY?)
public class FileAccessI implements Serializable{ ]$96#}7N
nXF|AeAco
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 z6Jfu:_N!
RandomAccessFile oSavedFile; H!ISQ8{V
long nPos; 0_5j(
<S%kwS
-)ag9{*
public FileAccessI() throws IOException H>2f M^
{ 7Ke#sW.HN
this("",0); Ty>g:#bogI
} V{G9E
vdN0YCXG
66~]7w
public FileAccessI(String sName,long nPos) throws IOException Dhe ]f#d
{ -,#LTW<.
oSavedFile = new RandomAccessFile(sName,"rw"); z;EnAy{9
this.nPos = nPos; l<mEGKB#
oSavedFile.seek(nPos); E8.xmTq
} #5.L%F
:,(ZMx\
L]HYk}oD.
public synchronized int write(byte[] b,int nStart,int nLen) kaj6C_k|
{ ';bovh@*
int n = -1; ZM%z"hO9R
try{ :-kXZe
oSavedFile.write(b,nStart,nLen); IW'2+EGc
n = nLen; c;e2= A
} Bswd20(w
catch(IOException e) J]|lCwF
{ \dag~b<
e.printStackTrace (); \LS+.bp%
} z~BrKdS
|E)IJj 3
VX;tglu2
return n; %Sdzr!I7*
} gZr/Dfy
O/=i'0Xv
_('KNA~
} kDG'5X;+
|cBpX+D
*AU"FI>V
/* NK@G0p~O
**SiteInfoBean.java &`'gO 9
*/ O$=)
package NetFox; .1F^=C.w
H19CVc\B
61J01(+|
public class SiteInfoBean { x@]pUA1
Ng} AEAFp
"HQH]?!k
private String sSiteURL; //Site's URL Y Hv85y
private String sFilePath; //Saved File's Path q(yw,]h]{
private String sFileName; //Saved File's Name zoV-@<Eh
private int nSplitter; //Count of Splited Downloading File L.xzI-I@D
SAEr$F^
&n:F])`2
public SiteInfoBean() yv<0fQ
{//nSplitter的缺省值为5 o2ndnIL
//default value of nSplitter is 5 q_N8JQg
this("","","",5); !Fz9\|
} sQS2U6
^m
EO;f`s)t
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) fxQN
{ ?7cF_Zvve
sSiteURL= sURL; M9@#W"
sFilePath = sPath; M#qZ0JT4
sFileName = sName; *S.2p*Vd
this.nSplitter = nSpiltter; I^{PnrB
p5~;8Q7
7 '@l?u/6
} 1lNg} !)[K
9 0[gXj
(r^IW{IndX
public String getSSiteURL() /y,~?
{ t _Q/v
return sSiteURL; x=qACoq
} rY>{L6d
15r<n
` m`Sl[6
public void setSSiteURL(String value) Nky%v+r
{ VB 8t"5
sSiteURL = value; +6!.)Ea=
} -NVk>ENL4
T!hU37g h?
2f]9I1{
public String getSFilePath() NDRk%_Eu(
{ O329Bkg
return sFilePath; A]{8=
} &Sc}3UI/F
MWCP/~>a2
C<6IiF[>%
public void setSFilePath(String value) >:s.`jV<
{ VYhZ0;' '
sFilePath = value; ,h1r6&MEY
} h.QKbbDj
zk4yh%Cd_
HFx8v!^5N
public String getSFileName() P$@5&/]
{ UG+wRX :dA
return sFileName; mV;Egm{A\
} d `Q$URn|
Lvc*L6
.J~iRhVOF
public void setSFileName(String value) z1LATy
{ ]P ->xJ
sFileName = value; m\4jiR_o
} h2KXW}y"4
mB#`{|1[
;G~0 VM2|
public int getNSplitter() 9h$-:y3
{ o"v> BhpC
return nSplitter; D|Z,eench
} QHsS|\u
jjz<V(Sk
"31GC7
public void setNSplitter(int nCount) Gn;eh~uw;l
{ + &b`QcH<
nSplitter = nCount; `ivr$b#
} m7e$Z
} d<qbUk3;
"aP>}5<h
E+"INX7
/* sj`9O-?49
**Utility.java (>>pla^
*/ .dp~%!"Sn,
package NetFox; x-Z`^O
:%A1k2
ix]3t^
public class Utility { @^;WC+\0
%I%F !M
ZH`6>:
public Utility() (1(3:)@S6
{ Os8]iNvW\
8R:H{)o~s}
`/]8C&u
} uHQJ&
42Vy#t/HC
//线程睡眠 *s?&)][
public static void sleep(int nSecond) 8{JTR|yB
{ : Ot\l
try{ h.4;-&
Thread.sleep(nSecond); pLBp[GQ
} J*,Ed51&7
catch(Exception e) PQvq$|q
{ 3VA8K@QiRm
e.printStackTrace (); S5v>WI^0h
} ;myu8B7&
} Gr?"okaA
C3bZ3vcW$
//日志 ?GD{}f33
public static void log(String sMsg) ozkN&0
{ rgIJ]vmy<H
System.err.println(sMsg); J}`K&DtM9
} 9T|7edl
D/{Tl
/n?5J`6
public static void log(int sMsg) **-%5~
{ ?$;_a%v6
System.err.println(sMsg); cGsxfwD
} 6l [TQ
} p4Vw`i+DnH
'iMI&?8u
,$vc*}yI0
/* 4VaUa8 D
**TestMethod.java +2B{"Czm
*/ k%:]PQjYT
package NetFox; #&r^~>,#L-
AWQwpaj-
dm.?-u;C
public class TestMethod { tI{ n!
W3*WR,z
{ j&|Em]
public TestMethod() j^iH[pN] \
{ ///xx/weblogic60b2_win.exe L\_8}\
try{ +#1WOQfAD
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); $./JA)`
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); )J~Qx-jG
SiteFileFetch fileFetch = new SiteFileFetch(bean); I^M3>}p
fileFetch.start(); } %S1OQC
} A[ /0on5r
catch(Exception e){e.printStackTrace ();} '4dnC2a]
5 ;dg#hO
gA2\c5F<
} XV%L6x
*[W!ng
bMkn(_H)\
public static void main(String[] args) <LZvG IMl
{ 3{on$\
new TestMethod(); Q`AJR$L
} ,O3"r;
} #hR}7K+@
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