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)); k;y5nXIlN
} v/DWy(CC
for(int i=0;i<nEndPos.length-1;i++) 5-X(K 'Q
{ s av
nEndPos = nStartPos[i+1]; aruT eJF
} w4p<q68
nEndPos[nEndPos.length-1] = nFileLength; FZhjI 8+,~
} !_UBw7Zm
} P&]PJt5
I!-5 #bxD
BnLE+X
//启动子线程 _LSf )
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 9l9|w4YJs
for(int i=0;i<nStartPos.length;i++) z}m)u
{ xu0pY(n^r
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), O_wRI\!
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ZnYoh/
nStartPos,nEndPos,i); ;;l-E>X0
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); |yow(2(F@
fileSplitterFetch.start(); 0xg6
} e!~x-P5M`
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), }fKpih
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 27KfT]=
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", a7Rg!%r
nEndPos = " + nFileLength); g{06d~Y
// fileSplitterFetch[nPos.length-1].start(); cH%#qE3
b:}+l;e52
\a\ApD
//等待子线程结束 JmK[7t
//int count = 0; BPzlt
//是否结束while循环 {]\!vG6
boolean breakWhile = false; 14v,z;HXj
=:-x;
(*2kM|
while(!bStop) 0<T/P+|
{ wsNM'~(
write_nPos(); Mw+8p}E
Utility.sleep(500); *6e 5T
breakWhile = true; .)eX(2j\
LAwAFma>
%@d~)f
for(int i=0;i<nStartPos.length;i++) *aF<#m v
{ |YAnd=$
if(!fileSplitterFetch.bDownOver) C7[CfcPA
{ =-qv[;%&6
breakWhile = false; #I.Wmfz
break; n7S~nk
} Eo }mSd
} xc+h Fx
if(breakWhile) F$Q@UVA
break; u*$ 1e
C}{$'#DV2
:2fz4n0{/
//count++; M(2c{TT
//if(count>4) a~F`{(Q2
// siteStop(); !mX 2
} CL$mK5u
tCdgtZm
:8~*NSEFd
System.err.println("文件下载结束！"); \;>idbV
} &v^LxLt+s
catch(Exception e){e.printStackTrace ();} E}$K&<J'-
} -l!;PV S|
[=Yfdh M8S
kEQ${F{
//获得文件长度 Wh)QCp0|n
public long getFileSize() X>#!s Lt
{ 7QlA/iKqK
int nFileLength = -1; 5!PU+9Kh
try{ F*_mHYa;
URL url = new URL(siteInfoBean.getSSiteURL()); H[{ch t h
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); \5%T'S@5
httpConnection.setRequestProperty("User-Agent","NetFox"); 0r+%5}|-K
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c!BiGw,;
int responseCode=httpConnection.getResponseCode(); W1s4[rL!Ht
if(responseCode>=400) m"!!)
{ :B<lDcFKJ
processErrorCode(responseCode); 5"[Qs|VjA6
return -2; //-2 represent access is error %@{);5[
} DaW_-:@s
UUx0#D/U0C
,z?Re)qm
String sHeader; 'lU9*e9
@,-xaZ[
$e! i4pM
for(int i=1;;i++) l\yFx
{ U&6!2s-
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); B=/*8,u
//Utility.log(in.readLine()); 8yH) 8:w
sHeader=httpConnection.getHeaderFieldKey(i); .s_wP
if(sHeader!=null) ~T')s-,l,:
{ 5s>$
if(sHeader.equals("Content-Length")) sYt8NsQ
{ 3H%oTgWk
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); > @ulvHL
break; C`D5``4
} uE>2*u\
} 3`&2-
else iaq0\d.[7
break; cvbv\G'aT
} !m$OI:rr
} l|fOi A*K
catch(IOException e){e.printStackTrace ();} (d[)U<
catch(Exception e){e.printStackTrace ();} ^z$-NSlI
MS6^= ["
@>J4K#"
Utility.log(nFileLength); ?<Dinq
Rp)82- .
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return nFileLength; 4b8!LzKS
} ,2)LH'Xx
E#_TX3B
)#r]x1[Kn
//保存下载信息（文件指针位置） GCx]VN3&
private void write_nPos() o_<o8!]l"
{ #Vanw!
try{ v.+-)RLQg
output = new DataOutputStream(new FileOutputStream(tmpFile)); YSt']
output.writeInt(nStartPos.length); ~_SV`io
for(int i=0;i<nStartPos.length;i++) Z8Fbx+~"
{ LD WFc_
// output.writeLong(nPos); Da)[mxJ
output.writeLong(fileSplitterFetch.nStartPos); CCX\"-C
output.writeLong(fileSplitterFetch.nEndPos); [t /hjm"$
} g[j"]~
output.close(); :JSOj@s
} m5sgcxt/
catch(IOException e){e.printStackTrace ();} +GWeu0b(~
catch(Exception e){e.printStackTrace ();} z@cL<.0CE
} Bya!pzbpr
Nl7"|()e
Fk>/
//读取保存的下载信息（文件指针位置） b:>(U.
private void read_nPos() z@$7T:H>
{ 7vV3"uns
try{ |-I[{"6q$@
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Y*0%lq({H
int nCount = input.readInt(); B5!$5Qc
nStartPos = new long[nCount]; {3C~cK{
nEndPos = new long[nCount]; bzmT.!
for(int i=0;i<nStartPos.length;i++) q[l},nw
{ ;*+jCL2F
nStartPos = input.readLong(); 5A/G?
nEndPos = input.readLong(); }7vX4{Yn
} @q2Yka
input.close(); :h N*
} )oa6;=go
catch(IOException e){e.printStackTrace ();} &&|*GAjJ
catch(Exception e){e.printStackTrace ();} B[Uvj~g
} 0W9,uC2:N
;|b D@%@
4_`+&
private void processErrorCode(int nErrorCode) .-[UHO05^8
{ *:3flJt
System.err.println("Error Code : " + nErrorCode); y-{^L`%Mk
} GLt#]I"LY
ooByGQ90V:
)=;0
//停止文件下载 on+ c*#
public void siteStop() <r,l
{ 4W~pAruwr
bStop = true; 9rtcI[&?0
for(int i=0;i<nStartPos.length;i++) Uw5z]Jck
fileSplitterFetch.splitterStop(); &?/h#oF@\
#Z}\;a{vZ
d$kGYMT"
} s*:J=+D]G
} "W|Sh#JF
//负责部分文件的抓取 3IZ^!J
**FileSplitterFetch.java CfoSow-
*/ Ip( IGR"
package NetFox; YrjF1hJ
-d6|D?}S
mKPyM<Q
import java.io.*; L\5j"] }`
import java.net.*; Ezm ~SY
1/3Go97/qV
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public class FileSplitterFetch extends Thread { Io{)@H"f
s<xD$K~rM
Wj/.rG&tE
String sURL; //File URL $k V^[
long nStartPos; //File Snippet Start Position KDuM;
long nEndPos; //File Snippet End Position fEWS3`Yy
int nThreadID; //Thread's ID X26gl 'U
boolean bDownOver = false; //Downing is over P8Fq %k
boolean bStop = false; //Stop identical EMmNlj6
FileAccessI fileAccessI = null; //File Access interface y1(smZU
Gb<)U[Hfd
t%n1TY,
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException UBrYN'QRNt
{ Ja|! fT
this.sURL = sURL; x,STt{I=
this.nStartPos = nStart; *]p]mzc
this.nEndPos = nEnd; C6ZM#}I$l
nThreadID = id; $OHY^IE(
fileAccessI = new FileAccessI(sName,nStartPos);//定位 #]oVVf_
} YL=?Nk/
nfq
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public void run() ^* ^te+N
{ {%'(IJ|5z
while(nStartPos < nEndPos && !bStop) ]YQlCx`
{ B8'" ^a^&-
i))S%!/r~
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try{ f[HhLAVGK`
URL url = new URL(sURL); }L{en
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); z"u4t.KpL
httpConnection.setRequestProperty("User-Agent","NetFox"); mZDrvTI'
String sProperty = "bytes="+nStartPos+"-"; vAbMU
httpConnection.setRequestProperty("RANGE",sProperty); =GTltFqI1
Utility.log(sProperty); GNA:|x
:kfHILi
gXZ.je)NM
InputStream input = httpConnection.getInputStream(); ;+g p#&i`
//logResponseHead(httpConnection); :Oo(w%BD]
/-b)`%Q|Y
*T*=~Y4kE
byte[] b = new byte[1024]; `$jc=ZLm
int nRead; VJS|H!CH
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ~(aQ!!H6
{ suN{)"
nStartPos += fileAccessI.write(b,0,nRead); 0 ML=]
//if(nThreadID == 1) &7!&]kA+
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Pk7Yq:avL
} O7I:Y85i#O
0PIC|
w-2p'u['Z
Utility.log("Thread " + nThreadID + " is over!"); R)"Ds}1G
bDownOver = true; `=RJ8u
//nPos = fileAccessI.write (b,0,nRead); Qa~o'
} OWxYV$
catch(Exception e){e.printStackTrace ();} E'?yI'~=
} t?L;k+sMM
} 9w^1/t&=04
U,yU-8z/
$(H%|Oyn
//打印回应的头信息 }+h/2D
public void logResponseHead(HttpURLConnection con) ^I@1y}xi
{ mVg-z~44T
for(int i=1;;i++) <LIL{g0eX
{ UJ1iXV[h"
String header=con.getHeaderFieldKey(i); BK]bSj
if(header!=null) n$g g$<
//responseHeaders.put(header,httpConnection.getHeaderField(header)); DnS# cs~
Utility.log(header+" : "+con.getHeaderField(header)); F=U3o=-:
else ,o& &d.
break; 2--"@@
} 3k py3z[%
} jxU1u"WU
%Wkvo-rOq
;t{Ew+s
public void splitterStop() dFFJw[$8w
{ nR-`;lrF~
bStop = true; XZLo*C!MG
} @tWyc%t
cJd~UQ<k
1T a48
} :3M2zV cf
IqJ7'X
L}*:,&Y/
/* {O9CYP:
**FileAccess.java [x ?38
*//文件访问(定位，写) JziuwL5,
package NetFox; wN\%b}pp
import java.io.*; o@mZ6!ax3
K9B_o,
Xp@8vu
public class FileAccessI implements Serializable{ A9' [x7N
uo;aC$US
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 l)< '1dqe
RandomAccessFile oSavedFile; IugYlt
long nPos; W+-a@)sh3Q
4HQP,
hqIYo .<
public FileAccessI() throws IOException N=^{FZ
{ Gx ci
this("",0); `mXbF
} [`nY/g:
")'o5V
YhYcqE8
public FileAccessI(String sName,long nPos) throws IOException 0OO$(R*
{ Dj}n!M`2I
oSavedFile = new RandomAccessFile(sName,"rw"); .[%em9u
this.nPos = nPos; 8\+kfK
oSavedFile.seek(nPos); D's'LspQ
} {</MC`
"jqC3$DKI
jX}}^XwX
public synchronized int write(byte[] b,int nStart,int nLen) <NZ^*]
{ -.-je"E
int n = -1; ,e{(r0
try{ 83~ Gu[
oSavedFile.write(b,nStart,nLen); DG,CL8bv
n = nLen; kY*3)KCp
} ,S5tkTa
catch(IOException e) z/6/
{ {U1 j@pKm
e.printStackTrace (); >Y=HP&A<
} ~SgW+sDFu
tgXIj5z
{j i;~9'Q
return n; c6FKpdn%
} "~jSG7h
0`.3`Mk
F4'g}yOLd
} qI;"yG-x-
X_GR{z%
7OY<*ny
/* ~nJcHJ1nb4
**SiteInfoBean.java SQ!wq
*/ ^Yz.,!B[
package NetFox; jiQJ{yY
eQ_dO]Q
sf )ojq6s
public class SiteInfoBean { eAKK uML
m8'B7|s
I{Hl2?CnI,
private String sSiteURL; //Site's URL y3l3XLI*b
private String sFilePath; //Saved File's Path i(P/=B
private String sFileName; //Saved File's Name RU&,z3LEb
private int nSplitter; //Count of Splited Downloading File Gh}k9-L
,0+%ji^V
~wG.'d]
public SiteInfoBean() 7|4hs:4mD
{//nSplitter的缺省值为5 QWVH4rg
//default value of nSplitter is 5 ;d$PQi
this("","","",5); *fyC@fI>
} ^DVj_&~
d'ddxT$GG
;AyE(|U+
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) W/_=S+CvK
{ fDyFkhc
sSiteURL= sURL; 6v~` jS%3
sFilePath = sPath; y,&.<Yc
sFileName = sName; b<,Z^Z_
this.nSplitter = nSpiltter; ]"bkB+I
jO xH'1I
n5CjwLgu\b
} XQL"D)fw
#?%akQ+w
KWtLrZ(j
public String getSSiteURL() .w5#V|
{ z d 9Gi5&
return sSiteURL; _~!*|<A_
} l{oAqTN
jR8~EI+
8tq6.%\
public void setSSiteURL(String value) |O0=Q,<m
{ *?jU$&Qpj*
sSiteURL = value; s/[15
} 0tbximmDb
i*34/
:&D>?{b0
public String getSFilePath() |Y'xtOMX
{ $nN`K*%
return sFilePath; Eq$Q%'5*ua
} R^zTgyr
]jo^P5\h>
bg.f';C
public void setSFilePath(String value) &4M0 S+.
{ ?DPNa
sFilePath = value; 2 mM0\ja
} &_X6m0z
v%RcwVt|
9^l[d<
public String getSFileName() &t)dE7u5
{ c\GJfsVk
return sFileName; K"'W4bO#7
} &8!*u3
ERxA79
=hE5 ?}EP+
public void setSFileName(String value) 2yqm$i9C
{ AWlR" p2
sFileName = value; [@D+kL*>
} WK7=z3mu
U9:?d>7
,EPs>#d
public int getNSplitter() cU}j Whu
{ l!Q |]-.@
return nSplitter; [s?H3yQ.
} A#9@OWV5f
cJ9:XWW
l:NEK`>i
public void setNSplitter(int nCount) (WT0j
{ }W&hPC
nSplitter = nCount; S.o 9AUv9
} )@DT^#zR
} aYQ!`mS::M
v5"5UPi-
X\3IY:Q@T
/* _Y@'<S.
**Utility.java PAF2=
*/ 1_vaSEov
package NetFox; KobNi#O+
J;+AG^U<
SF*!Z2K
public class Utility { i9}n\r0=c
2^ 'X
;OW`(jC
public Utility() FG8genCH@
{ 4xLU15C
3\eb:-B:@
iN%\wkx*N
} #W<D~C[I _
]>h2h?2te
//线程睡眠 S9X~<!]
public static void sleep(int nSecond) u?[P@_i<
{ n y6-_mA]
try{ FY"!%)TV
Thread.sleep(nSecond); v ?@Ys+V
} 8.D$J
catch(Exception e) \~ O6S`,
{ 2d+IROA
e.printStackTrace (); )W9$_<Z
} @ -pi
} CFD& -tED&
p1t9s N,
//日志 L+Q"z*W
public static void log(String sMsg) +=I_3Wtth
{ u->UV:u
System.err.println(sMsg); ]D&$k P(
} W&`_cGoP
K1RTAFf /
2!/*I:
public static void log(int sMsg) Y<Y5HI"
{ \XwXs5"G
System.err.println(sMsg); @=x=dL(
} Q%4>okj,
} ) ^PY-~o[
N3E Qq~lX
MO)N0{.b
/* o?uTL>Zin
**TestMethod.java :pQZ)bF
*/ !]qwRB$5
package NetFox; CD1}.h
z<_{m4I;
EOhUr=5~
public class TestMethod { b8)>:F
}S'+Ytea
H@2JL.(k
public TestMethod() /Kb7#uq
{ ///xx/weblogic60b2_win.exe SFKW"cP
try{ Z[KXDQn8
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); B&|F9Z6D
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); y|V/xm+Fp
SiteFileFetch fileFetch = new SiteFileFetch(bean); 0[}"b(O{
fileFetch.start(); Md'd=Y_0
} 5T}$+R0&
catch(Exception e){e.printStackTrace ();} kV"';a
!I5_ln
UzFd@W u#
} AR'q2/cw
[La=z7*
esmQ\QQ^1
public static void main(String[] args) 1g{`1[.QO
{ 0rY<CV;fZ
new TestMethod(); 9ZUG~d7_
} JE,R[` &
} E,E:WuB
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