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)); ']]&<B}mz
} GXE6=BO
for(int i=0;i<nEndPos.length-1;i++) ,$qqHSd1M
{ qm&Z_6Pw
nEndPos = nStartPos[i+1]; f!"Y"g:@E
} 'F[ C 4
nEndPos[nEndPos.length-1] = nFileLength; }&mFpc
} ef;Ta|#
} 0piBK=tE/
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_7M!b9oA
//启动子线程 ToB^/ n[
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; VI(;8
for(int i=0;i<nStartPos.length;i++) ]O;Hlty(g
{ b88Zk*
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), |_P-
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ?$T39U^
nStartPos,nEndPos,i); 96.z\[0VZ
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); qJ|n73yn
fileSplitterFetch.start(); r4D6I,
} j_r7oARL
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 7q] @Jx9
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); k9^Vw+$m
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", X}5aE4K/
nEndPos = " + nFileLength); d$G<g78D
// fileSplitterFetch[nPos.length-1].start(); b:iZ.I
MK<VjpP0(
7Z;w<b~
//等待子线程结束 s;0eD5b>x
//int count = 0; iC{~~W6
//是否结束while循环 G{cTQH|
boolean breakWhile = false; :~2An-V
kH43 T
[?$|
while(!bStop) Gkr^uXNg#
{ f2#9E+IQ
write_nPos(); R "&(Ae?LR
Utility.sleep(500); ($oO, c'z
breakWhile = true; ^!*?vHx:
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ZQ^kS9N i
for(int i=0;i<nStartPos.length;i++) '1}rQqZ
{ A!kNqJ2
if(!fileSplitterFetch.bDownOver) YORFq9a{R
{ 7\ <4LX
breakWhile = false; ~Lc>~!!t
break; q-.e9eoc\
} !vQ!_|g1
} 1@ j>2>i
if(breakWhile) I>27U<PX
break; >t"]gQHtx
(Jw[}&+
!k&~|_$0@
//count++; Te8BFcJG
//if(count>4) id-VoHdK
// siteStop(); Hr$oT=x[
} MGO.dRy_
c#G]3vTdE
n(Up?_
System.err.println("文件下载结束！"); $l&&y?()
} tH:K6^oR
catch(Exception e){e.printStackTrace ();} }eX_p6bBw
} 6[9E^{(z
;UgRm#
k"SmbFn%N0
//获得文件长度 bH41#B
public long getFileSize() oPNYCE
{ y0qE::/H$
int nFileLength = -1; wS2iyrIB
try{ >:]fN61#
URL url = new URL(siteInfoBean.getSSiteURL()); \QUvImT
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ,h2q37
httpConnection.setRequestProperty("User-Agent","NetFox"); ru`;cXa,
T^a {#B
!v2,lH
int responseCode=httpConnection.getResponseCode(); hh"0z]
if(responseCode>=400) LeW.uh3.
{ qD\%8l.]Z
processErrorCode(responseCode); lq@Vb{Z
return -2; //-2 represent access is error AEwb'
} {K'SOhH4?
8mA6l0
|4Ix2GD
String sHeader; 04;y%~,}U/
ABV\:u
,l<-*yMD
for(int i=1;;i++) z1+rz%
{ FGx_qBG4|
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); Hcd>\0
//Utility.log(in.readLine()); i&,U);T
sHeader=httpConnection.getHeaderFieldKey(i); ~,e!t.339
if(sHeader!=null) t%z7#}9$
{ >*}qGk
if(sHeader.equals("Content-Length")) 3i(k6)H$4
{ SEchF"KJQF
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); BHmA*3?
break; ~rCnST
} n@L!{zY
} <J-OwO a-1
else 8"LaP3U
break; _3p:q.
} l``1^&K
} }WGi9\9T&
catch(IOException e){e.printStackTrace ();} F.8{ H9`
catch(Exception e){e.printStackTrace ();} M{kPEl&Z
6sy%KO*A
o33{tUp'
Utility.log(nFileLength); +lha^){
l3MbCBX2
qd|*vE
return nFileLength; `A <yDy
} UxicqkX
*gz{:}NX
#>'1oC{
//保存下载信息（文件指针位置） H[N&Wiq/|
private void write_nPos() pjj 5
{ G^mk<pH
try{ rF0zGNH
output = new DataOutputStream(new FileOutputStream(tmpFile)); $fKwJFr
output.writeInt(nStartPos.length); L)nVNY@Mc
for(int i=0;i<nStartPos.length;i++) om_&|9B)
{ h.=B!wKK
// output.writeLong(nPos); uWnS<O
output.writeLong(fileSplitterFetch.nStartPos); &<Gq-IN
output.writeLong(fileSplitterFetch.nEndPos); 1]>KuXd r
} j|G-9E
output.close(); oZCi_g 5i
} a3c4#'c|D
catch(IOException e){e.printStackTrace ();} nnGA_7-t
catch(Exception e){e.printStackTrace ();} g[M@
} T4!]^_t^
qk,cp},2K
qfYb\b
//读取保存的下载信息（文件指针位置） 18A&[6"!
private void read_nPos() A[ iPs9
{ "}HQ)54&
try{ _Mt:^H}Sy
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); aY:(0en]&
int nCount = input.readInt(); f,L
nStartPos = new long[nCount]; pn $50c
nEndPos = new long[nCount]; sId5pY!
for(int i=0;i<nStartPos.length;i++) :s'%IGy>:
{ 93WYZNpX
nStartPos = input.readLong(); ygfqP
nEndPos = input.readLong(); &HXSO,@
} FY|x<-f
input.close(); hE6tu'
} ewY[vbF
catch(IOException e){e.printStackTrace ();} >Ed^dsb&
catch(Exception e){e.printStackTrace ();} |%V.Lae
} fBLd5
qBNiuV;*
`X^e}EGWu
private void processErrorCode(int nErrorCode) GC\/B0!
{ Ez$5wY^J
System.err.println("Error Code : " + nErrorCode); >(*jbL]p
} f<;9q?0VF
.FXQ,7mZ-
f.P( {PN
//停止文件下载 ;Z`)*TRp4
public void siteStop() kTk?[BK
{ {f&ga
bStop = true; _uu:)%
for(int i=0;i<nStartPos.length;i++) :> q?s
fileSplitterFetch.splitterStop(); Y>#c2@^i<
j d81E
OXacI~C
} *(scSC>
} ]Cz16e&=2
//负责部分文件的抓取 aBI]' D;
**FileSplitterFetch.java >Qx#2x+
*/ "|G,P-5G"
package NetFox; ^]DWrmy
lhI;K4#
IcoL/7k3
import java.io.*; f!J^vDl
import java.net.*; ^`!Daqk
e"CLhaT
+-nQ, fOV
public class FileSplitterFetch extends Thread { aOD"z7}U
Ax^'unfQ:
``<1Lo@
String sURL; //File URL ^"l$p,P+
long nStartPos; //File Snippet Start Position Qm.kXlsDI
long nEndPos; //File Snippet End Position []]3"n
int nThreadID; //Thread's ID @ tIB'|O
boolean bDownOver = false; //Downing is over `@eH4}L*
boolean bStop = false; //Stop identical E nvs[YZe
FileAccessI fileAccessI = null; //File Access interface 9>#|~P&FE
%KA/
_)l %-*Z7p
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException gCJ'wv)6|%
{ 84[^#ke
this.sURL = sURL; r9Z/y*q
this.nStartPos = nStart; 19.cf3Dh
this.nEndPos = nEnd; $;CC lzw
nThreadID = id; DsX>xzM
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ZH(.|NaH
} 1;P\mff3Y
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WNb$2q=
public void run() ZYsFd_
{ /(V=Um^0
while(nStartPos < nEndPos && !bStop) >&&xJ5
{ t4IJ%#22
=vc5,
Rpk`fxAO
try{ `"H?nf0
URL url = new URL(sURL); 4cQ5E9
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); mvgm o
httpConnection.setRequestProperty("User-Agent","NetFox"); Flxo%g};
String sProperty = "bytes="+nStartPos+"-"; `0^i #
httpConnection.setRequestProperty("RANGE",sProperty); *jK))|%
Utility.log(sProperty); i-?zwVmn
@;6}xO2
y2R=%EFh6
InputStream input = httpConnection.getInputStream(); re!8nuBsA
//logResponseHead(httpConnection); %-l:_A
PBL^xlg
#& wgsGV8C
byte[] b = new byte[1024]; ?Qig$
int nRead; M: "ci;*$
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) rl%Kn^JJ~
{ ElXe=5L\#
nStartPos += fileAccessI.write(b,0,nRead); 6 b}feEh$!
//if(nThreadID == 1) 'D&G~$
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); !7)ID7d
} #'x?)AS
5Mr;6 ]I<
{_Qxe1^g
Utility.log("Thread " + nThreadID + " is over!"); &%X Jf~IQ
bDownOver = true; 3@] a#>
//nPos = fileAccessI.write (b,0,nRead); 4QFOO sNp
} pU]{Z(
catch(Exception e){e.printStackTrace ();} 3~</lAm;
} %5*#c*)R
} FA9e(Ha
w.aFaR)04
{0e{!v
//打印回应的头信息 ['emP1g~
public void logResponseHead(HttpURLConnection con) %h"< IA S.
{ Z5Ihc%J^
for(int i=1;;i++) _)E8XyzF
{ qm=F6*@}
String header=con.getHeaderFieldKey(i); 0xUj#)
if(header!=null) {,FeNf46
//responseHeaders.put(header,httpConnection.getHeaderField(header)); " B{0-H+
Utility.log(header+" : "+con.getHeaderField(header)); 4p8jV*:@{
else ZPsY0IzLo
break; ?0NSjK5ma
} Ro]IE|Fv
} %"Q!5qH&
<88}+j
hZWK5KwT
public void splitterStop() iFG5%>5F
{ )95yV;n
bStop = true; 2U'JzE^Do
} :5M}Iz7
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+g6j=%
} )ek 5
XOg(k(&T
KOEi_9i}
/* DD 5EHJR
**FileAccess.java Gu`Vk/&
*//文件访问(定位，写) **r?
package NetFox; ,,_K/='m
import java.io.*; |D`b7h
Y"kS!!C>[
UT<bv}(J
public class FileAccessI implements Serializable{ Qz)8eIO:
0D3+R1>_D
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 k*3_) S -
RandomAccessFile oSavedFile; %4|}&,%%r
long nPos; ^Pg YP
WFB|lNf&
@\`G & VB
public FileAccessI() throws IOException q4GW=@eD
{ DgT.Lku?
this("",0); $;i$k2n:
} ]a!; `m$
T:%wX9W
PnIvk]"Ab
public FileAccessI(String sName,long nPos) throws IOException #D/ }u./
{ uU(G_E ?
oSavedFile = new RandomAccessFile(sName,"rw"); 8+|V!q
this.nPos = nPos; p5;,/ |Ft
oSavedFile.seek(nPos); w+9C/U;|s
} J=SB/8tQ)T
6a]f&={E
oB06{/6
public synchronized int write(byte[] b,int nStart,int nLen) 0/P-> n~
{ W|rFl]~a
int n = -1; =R;1vUio
try{ vYR=TN=Z4
oSavedFile.write(b,nStart,nLen); 0tm_}L$g=b
n = nLen; 4a.e ,gitf
} e4YfTr
catch(IOException e) pL}j ZTo
{ 0SCW2/o8
e.printStackTrace (); (zJ$oRq
} o*wC{VP_
";?C4%L
2@m(XT (
return n; v8[ek@
} -?w v}o
%Di7u- x
ds$\vSd
} :KV,:13`D
AV[PQI
JIbzh?$aD
/* XJlDiBs9=Q
**SiteInfoBean.java U~#^ ^
*/ >RL6Jbo|
package NetFox; `k{ff
w[YkTv
:Bv&)RK
public class SiteInfoBean { ~?`9i>3W~
Kjn&
|6(qg5"
private String sSiteURL; //Site's URL t`8e#n 9
private String sFilePath; //Saved File's Path =O3I[
private String sFileName; //Saved File's Name A.$VM#
private int nSplitter; //Count of Splited Downloading File j^$3vj5E[
d%_78nOh"
lQ<#jxp
public SiteInfoBean() tU)r[2H2
{//nSplitter的缺省值为5 }OP%p/eY
//default value of nSplitter is 5 WrHgF*[
this("","","",5); [Z5}2gB&
} DA4edFAuE
q(&^9"
_]=TFz2O
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) (J^Lqh_
{ N1+4bR
sSiteURL= sURL; r>Qyc
sFilePath = sPath; rq'##`H
sFileName = sName; 3vRLg b
this.nSplitter = nSpiltter; #zSi/r/=1
0.u9f`04
TM/|K|_
} iB}LnC:
S4k^&$;
qrM{b=
public String getSSiteURL() Ft"&NtXeZZ
{ MgH1d&R
return sSiteURL; zqvRkMWcM
} vSYunI
@wEKCn|}o
s;-78ejj7
public void setSSiteURL(String value) +YQ~t,/
{ FU]8.)`G
sSiteURL = value; 3lLW'g&=
} +;:aG6q+
"9U+h2#]
j:v~MrQ7|
public String getSFilePath() mI?* Z%>g
{ =2;mxJ#o
return sFilePath; '.%iPMM
} W>q*.9}Y"
Jv 6nlK`
~ F?G5cN5
public void setSFilePath(String value) t-eKruj+
{ _#J_$CE#
sFilePath = value; P^K?E
} "LP, TC
1IOo?e=/bM
_gPVmGG
public String getSFileName() 2<y}91N:
{ n!kk~65|
return sFileName; XQ0#0<
} u5cVz_S
To#E@Nw
LY\ddI*s
public void setSFileName(String value) 0okO+QU,a
{ ;B|^2i1Wi
sFileName = value; #uD)0zdw
} e9z$+h
u|m[(-`
gJFR1
public int getNSplitter() B&4fYpn
{ >+Sv9S
return nSplitter; e'k;A{Oh
} ueWR/
%jbJ6c
*2qh3
public void setNSplitter(int nCount) _S9rF-9G]
{ 629~Uc6]
nSplitter = nCount; 9atjK4+o
} Z;j/K
} ||{T5E-.F
5YTb7M
Eu`2w%qz
/* 2y9:'c|
**Utility.java T@K7DkP@
*/ w|!YoMk+o
package NetFox; ^f^-.X
KAj"p9hq+k
_Hz~HoNU
public class Utility { iwG>]:K3
3iu!6lC
L\/u}]dPQ
public Utility() SWNU1x{,c\
{ 3o+KP[A
L?=#*4t
Hk<X
} d'N(w7-Y
hw&ke$Fg#
//线程睡眠 eW\?eq+ `A
public static void sleep(int nSecond) Ph(]?MG\_
{ XysFwi
try{ k%EWkM)?
Thread.sleep(nSecond); 2gQY8h8
} Pcs^@QP
catch(Exception e) L Yh@ u1p
{ pchQ#GU
e.printStackTrace (); i_|9<7a
} ?o2;SY(-
} uI%N?
+Od1)_'\D3
//日志 *A~($ZtL
public static void log(String sMsg) ;jRL3gAe)
{ [n!$D(|"!V
System.err.println(sMsg); 9nT?|n]>
} ~/^y.SsWM
mV6#!_"
<u6c2!I{
public static void log(int sMsg) MZCL:#
{ .@y{)/
System.err.println(sMsg); bWGyLo,
} 6@"Vqm|HD
} @IEI%vH
>|l;*Kw,/P
X4d Xm>*?=
/* gbYLA a
**TestMethod.java D3<IuWeM
*/ >}ro[x`K
package NetFox; 9b?i G
3x04JE3!
[:AB$l*
public class TestMethod { 5Z* b(R
|$YyjYK
BhqhyX\D&y
public TestMethod() \w{@u)h
{ ///xx/weblogic60b2_win.exe ,]0S4h67
try{ 17e=GL
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); J)-T:.i|0
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ?F!EB4E\y}
SiteFileFetch fileFetch = new SiteFileFetch(bean); .i MnWW
fileFetch.start(); 5,F;j<F
} cDfx)sL
catch(Exception e){e.printStackTrace ();} LiiK3!^i
4st~3,lR$
t{+M|Y
} o)0C-yO0qf
77+|#<J
]b}B~jD
public static void main(String[] args) CkRyzF
{ [?;`x&y~y
new TestMethod(); TcR=GR*cJ
} X7e>Z)l
} qIB>6bv#x
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