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(>hboR5n
} Q_<CG[,6D1
for(int i=0;i<nEndPos.length-1;i++) X(m&
{ !^ko"^p
nEndPos = nStartPos[i+1]; 4%#C _pE9
} :cv_G;?
nEndPos[nEndPos.length-1] = nFileLength; P$MAURFm
} Yrb[:;Y
} a=LjFpv/]
!"\UT&
LD]>_P83
//启动子线程 wy3{>A Z(
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; sWp]Zy
for(int i=0;i<nStartPos.length;i++) \TM%,RC3K
{ *c}MI e'&
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), qp>V\h\
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ]$)J/L(p/]
nStartPos,nEndPos,i); Rn={:u4
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); jBexEdH
fileSplitterFetch.start(); bqmOfGM
} SooSOOAx[
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Z/=x(I0
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Pyc/6~?
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", {b4+ Yc
nEndPos = " + nFileLength); (dO, +~
// fileSplitterFetch[nPos.length-1].start(); ,@2d<d]
g`)2I+L7
0w?\KHT
//等待子线程结束 't3/< h<
//int count = 0; zItf>j7|Z
//是否结束while循环 !2oe;q2X[G
boolean breakWhile = false; }0Isi G
so h3d
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while(!bStop) ,}%+5yH
{ 2lw0'
write_nPos(); (r_xs
Utility.sleep(500); a@_.uD
breakWhile = true; #7OUqp
{Z<4
F5Tah{
for(int i=0;i<nStartPos.length;i++) b?U!<s.
{ ^7Q}W#jy
if(!fileSplitterFetch.bDownOver) lUXxpv1m
{ CA[-\>J7y
breakWhile = false; !( xeDX
break; PE1F3u>O
} hz8Y2Ew
} >/;V_(
if(breakWhile) n m4+$GW
break; F-%wOn /
k?|l;6
;c"T#CH.
//count++; (7w`BR9B
//if(count>4) fk%r?K6K
// siteStop(); 4}B9y3W:v
} 7_>No*[
7VkT(xnm
aL@myq.
System.err.println("文件下载结束！"); VZNMom,Wr
} ;'!G?)PZ
catch(Exception e){e.printStackTrace ();} |]`\ak
} oGpyuB@A/
)&[S*g
F3/aq+<P[
//获得文件长度 f,Vj8@p)x
public long getFileSize() Tvr2K84l
{ 1MI/:vy-
int nFileLength = -1; R.Xh&@f`
try{ (Nd5VuI
URL url = new URL(siteInfoBean.getSSiteURL()); DYlu`j_ux
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); "`Q~rjc$2
httpConnection.setRequestProperty("User-Agent","NetFox"); ?.#?h>MS{s
M{$EJS\d=
]8*#%^
int responseCode=httpConnection.getResponseCode(); XiE
if(responseCode>=400) d0YN:lJc
{ ~0 <?^
processErrorCode(responseCode); }=Yvs)
return -2; //-2 represent access is error E/@w6uIK[
} L 1=HD
E/9h"zowS
,a&N1G.
String sHeader; #|76dU
xwG=&+66
uxF88$=!t
for(int i=1;;i++) VH1PC
{ Eh\0gQ=
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); e,/b&j*4th
//Utility.log(in.readLine()); _gZ8UZ)
sHeader=httpConnection.getHeaderFieldKey(i); ?2l#=t?PP
if(sHeader!=null) [xiZkV([
{ VA*~RS
if(sHeader.equals("Content-Length")) 1ipfv-hb6
{ q6'3-@%
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); NqcmjHvy
break; in_~,fd
} !|K~)4%rj
} Z+h^ ie"g
else /7#KkMg
break; -.=q6N4
} "2HSb5b"`
} <H3njv
catch(IOException e){e.printStackTrace ();} iLf:an*vH
catch(Exception e){e.printStackTrace ();} @D_=MtF<
w7NJ~iy
ed$g=qs>
Utility.log(nFileLength); kylR)
"X~ayn'@w,
p.,o@GcL~
return nFileLength; HlEp Dph%
} !HyPe"`oL
"/6<k0.D&
Nx>WOb98
//保存下载信息（文件指针位置） K2PV^Y
private void write_nPos() e _\]Q-
{ S'~Zlv3`
try{ :Z|lGH =
output = new DataOutputStream(new FileOutputStream(tmpFile)); c(jF^ 0~
output.writeInt(nStartPos.length); | _/D-m*
for(int i=0;i<nStartPos.length;i++) 1(6B|w5+
{ 9 ![oJ3
// output.writeLong(nPos); &>kklP
output.writeLong(fileSplitterFetch.nStartPos); #;GIvfW
output.writeLong(fileSplitterFetch.nEndPos); /rp.H'hC
} \,jrug<C$^
output.close(); Qzy[
} {H OvJ`tM
catch(IOException e){e.printStackTrace ();} $P#Cf&R
catch(Exception e){e.printStackTrace ();} Wlm%W>%
} 6kH47Yc?
F?=(4Pyvu
V*P3C5l
//读取保存的下载信息（文件指针位置） 7e$\|~<
private void read_nPos() (3YqM7cqt
{ F#S^Q`
try{ qGG
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); J{8_4s!Xt>
int nCount = input.readInt(); 0&$+ CWSM
nStartPos = new long[nCount]; R=ddQ:W6g
nEndPos = new long[nCount]; P~nI6/r1
for(int i=0;i<nStartPos.length;i++) n]I_LlbY
{ Fhw:@@=
nStartPos = input.readLong(); j3 d=O!
nEndPos = input.readLong(); (5[|h
} n\k6UD
input.close(); AD$k`Cj
} o"D`_ER
catch(IOException e){e.printStackTrace ();} Rz% Px:M
catch(Exception e){e.printStackTrace ();} [OJ@{{U%
} m)4s4P57y
AnVj '3
jG=*\lK6
private void processErrorCode(int nErrorCode) A[L+w9
{ |@pJ]
System.err.println("Error Code : " + nErrorCode); Gs$<r~Tg
} F,{M!dL
F. X{(8
PZ2$ [s0W
//停止文件下载 k]FP1\Y
public void siteStop() >Ya+#j~CZ
{ hU=n>g>nx
bStop = true; /C"dwh"``
for(int i=0;i<nStartPos.length;i++) {'dpRq{c|
fileSplitterFetch.splitterStop(); |aef$f5
hPtSY'_@_
xXQ#?::m
} Q:?]:i/*
} lO},fM2j
//负责部分文件的抓取 Omo1p(y
**FileSplitterFetch.java 8mTjf Br
*/ `?VtB!p@x=
package NetFox; :Bc)1^I
1c);![O
De`)`\U
import java.io.*; g2%&/zq/
import java.net.*; .Q FGIAM
VyK]:n<5Q
*=i|E7Irg
public class FileSplitterFetch extends Thread { 7M#2Tze}
5`,qKJ
!`S?
String sURL; //File URL |,CWk|G
long nStartPos; //File Snippet Start Position )f]E<*k'E
long nEndPos; //File Snippet End Position i/QE)"B"q
int nThreadID; //Thread's ID c/.U<
boolean bDownOver = false; //Downing is over N}x\Ll
boolean bStop = false; //Stop identical prE~GO7Z
FileAccessI fileAccessI = null; //File Access interface :3F&NsgHH
<;\T e4g[
J =o,: 3"
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException K FV&Dt}<
{ [ 9)9>-
this.sURL = sURL; m=i8o `
this.nStartPos = nStart; E>~DlL%
this.nEndPos = nEnd; {IEc{y7?gO
nThreadID = id; NN1d?cOn
fileAccessI = new FileAccessI(sName,nStartPos);//定位 e$>.x< Eq
} %lPAq
_YzItge*
tcOgF:
public void run() F VW&&ft
{ 8 PI>Q
while(nStartPos < nEndPos && !bStop) kQ4-W9u
{ %g7 !4
9`4mvK/@
H@0i}!U64
try{ qk~ni8
URL url = new URL(sURL); JmB7tRM8
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Lf_`8Ux
httpConnection.setRequestProperty("User-Agent","NetFox"); `` (D01<
String sProperty = "bytes="+nStartPos+"-"; 0/?V _
httpConnection.setRequestProperty("RANGE",sProperty); o>x*_4[
Utility.log(sProperty); @czNiWU"4;
.Ymoh>JRL
+')\,m "z
InputStream input = httpConnection.getInputStream(); Sz4YPl
//logResponseHead(httpConnection); _?Zg$7VJ
HJ[@;F|aU
4UD7!
byte[] b = new byte[1024]; >mRA|0$
int nRead; :lz@G4=C
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) KP" lz
{ a$!|)+
nStartPos += fileAccessI.write(b,0,nRead); ju#/ {V;D
//if(nThreadID == 1) em`z=JGG
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); )s^D}I(
} |x*~PXb
` MIZqHM @
1HYrJb,d
Utility.log("Thread " + nThreadID + " is over!"); :f (UZmV$
bDownOver = true; xab1`~%K
//nPos = fileAccessI.write (b,0,nRead); 6J[ {?,
} dWV.5cViP
catch(Exception e){e.printStackTrace ();} !mhV$2&r
} ,Cx @]]
} Wkw.z
fT1/@
<A?- *
//打印回应的头信息 ]5W|^%
public void logResponseHead(HttpURLConnection con) +[C(hhk("
{ &rs+x<
for(int i=1;;i++) Xy[O
{ ) jBPt&
String header=con.getHeaderFieldKey(i); K?0f)@\nx
if(header!=null) "<6X=|C
//responseHeaders.put(header,httpConnection.getHeaderField(header)); {xb8H
Utility.log(header+" : "+con.getHeaderField(header)); dLl/V3C6t
else lA}(63j+b
break; e]-bB#-A
} xgV.<^
} Htd-E^/
KhK:%1po
Gkci_A*
public void splitterStop() @-y.Y}k#$~
{ UMsJg7~
bStop = true; *aF#on{
} Dizc#!IGU
>jxo,xz
|r2U4^
} !K:
e=$p(
x=(y
/* AA[(rw
**FileAccess.java gZbC[L
*//文件访问(定位，写) apsR26\^
package NetFox; G3O`r8oZcJ
import java.io.*; Gs^hqT;h
R7%' vZk
V<&x+?>S
public class FileAccessI implements Serializable{ x {Z_rD
A.nU8
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 c*LB=;npI
RandomAccessFile oSavedFile; f5p>oXo4b
long nPos; Pi|WOE2
;"/[gFD5u
Q/'jwyj_
public FileAccessI() throws IOException K,f*}1$qM
{ M*ZR+pq,
this("",0); )`;Q]?D
} c^$_epc*
LLE\;,bv
dO/iL7K&
public FileAccessI(String sName,long nPos) throws IOException R+vago:
{ D; xRgHn
oSavedFile = new RandomAccessFile(sName,"rw"); N]gJ(g
this.nPos = nPos; B!:%^S
oSavedFile.seek(nPos); yV`H_iC
} {')L*
6lW\-h`NG
tf?syk+jB7
public synchronized int write(byte[] b,int nStart,int nLen) N.r8dC
{ f.Wip)g
int n = -1; (bpO>4(S
try{ CG@3z@*?.
oSavedFile.write(b,nStart,nLen); 7wKN
n = nLen; FKhmg&+>
} LIzdP,^pc
catch(IOException e) (I(?oCQ
{ z4GcS/3K
e.printStackTrace (); )UBU|uYR\
} %eK=5Er jx
Sg#$ B#g
x"/DCcZ
return n; k:1p:&*m
} aMaICM
C(N' +VV_
/ =]h@m-`
} SP}!v5.
(>~:1
`" BFvF#
/* H&$L1CrdL
**SiteInfoBean.java qUNK Dt
*/ }le}Vuy\s
package NetFox; Y~ku?/"6T
c~1+5&
0PfjD
public class SiteInfoBean { B49: R>
6-"@j@l5<
Vr/UY79
private String sSiteURL; //Site's URL (2 nSZRB
private String sFilePath; //Saved File's Path EI+RF{IKh
private String sFileName; //Saved File's Name Ep>} S
private int nSplitter; //Count of Splited Downloading File ?w^MnK0U)
c?ZM<Y"
AkMP)\Q
public SiteInfoBean() }57s
{//nSplitter的缺省值为5 ZLP)i;Az
//default value of nSplitter is 5 +pcGxje\
this("","","",5); ^"lVTDsU
} (^_j,4
@aQ};~
CGyw '0S
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) a^{"E8j
{ YK xkO
sSiteURL= sURL; n 0/<m.
sFilePath = sPath; ,\fp.K<
sFileName = sName; *A<vrkHz
this.nSplitter = nSpiltter; \zCw&#D0Z
_E\Cm
}4Q~<2
} 3?%?J^/a
]1Wh3C
<8J_[ S
public String getSSiteURL() CjRU3 (Q
{ N.~zQVO#R
return sSiteURL; -hd@<+;E
} G4&vrM,f
e\8|6<o[
+aY]?]
public void setSSiteURL(String value) XRQz~Py
{ H18.)yHX
sSiteURL = value; LyRbD$m
} )~X.x"}8k
b((>?=hh
Zk:Kux[7
public String getSFilePath() OrC}WMhd
{ 4Tdp;n\F
return sFilePath; Mg"e$m
} ,1K`w:uhS
_O,k0O
Q[n*ce7L0
public void setSFilePath(String value) gJ=y7yX
{ W1;QPdz:
sFilePath = value; Xp67l!{v
} >TQNrS^$J
s~p(59
;2y4^
public String getSFileName() =&K8~
{ iNCT(N~.
return sFileName; f>CJ1;][{
} ;% <[*T:*'
K[q{)>,9
oKMr Pr[`
public void setSFileName(String value) 7 /6Zp?
{ zG* >g
sFileName = value; N^Hj%5
} jk\z-hd
0h-'TJg*sk
fxQ4kiI
public int getNSplitter() `GUGy.b
{ "Snt~:W>
return nSplitter; GBY-WN4sc[
} 0$g;O5y"i
8wEUly
XN&cM,
public void setNSplitter(int nCount) +\R__tx;
{ ]N;\AXZ7
nSplitter = nCount; gyz_$T@x
} X,A]<$ACu%
} ]x(cX&S-9
/lS5B6NU
}'p"q)
/* }&LVD$Bz
**Utility.java R>D[I.
*/ R wTzS;
package NetFox; <kCOg8<y :
E[ttamU
HO_!/4hrU
public class Utility { egmNX't6f5
yZV Y3<]
r"|UgCc
public Utility() 5AbY 59
{ XiMd|D
XW.k%H4@
Nu;?})tF
} HcQ)XJPK
QJy1j~9x
//线程睡眠 2,6~;R
public static void sleep(int nSecond) 0N87G}Xu
{ mUNAA[0 L
try{ 9RPZj>ezjA
Thread.sleep(nSecond); ;(-Wc9=
} tc0(G~.N
catch(Exception e) $@HW|Y
{ eg1Mdg\a
e.printStackTrace (); R>t?6HOcp
} Itz[%Dbiq9
} YuUJgt .1
wEF"'T
//日志 z"c,TlVN3
public static void log(String sMsg) /|p\l"
{ 5gSe=|we*p
System.err.println(sMsg); YU`}T<;bg
} !l-Q.=yw
YB1Jv[
c'INmc I|
public static void log(int sMsg) J9/EJ'My
{ Urz9S3#\
System.err.println(sMsg); .L~ NX/V
} t"Bp# U1
} `&:>?Y/X2
SyI\ulmL
QM24cm T
/* ?PYZW5
**TestMethod.java 5\Rg%Ezl
*/ C]Q`!e
package NetFox; }X6w"
]$BC f4:
"/ySHB[
public class TestMethod { Pm]lr|Q{I
& }7+.^
u2S8DuJ
public TestMethod() >K<cc#Aa
{ ///xx/weblogic60b2_win.exe H;seT XL
try{ Qv<p$Up6
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); `MHixQ;j
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Q@uWh:
SiteFileFetch fileFetch = new SiteFileFetch(bean); Ob/i_
fileFetch.start(); R7 rO7M!
} =M6{{lI/
catch(Exception e){e.printStackTrace ();} 5@J]#bp0M
~3Za"q*0s
Mh2Zj
} TBIr^n>Z<k
VU1Wr|
"g*`G<W_s
public static void main(String[] args) K 6yD64
{ ;jJ4H+8
new TestMethod(); J|F!$m{
} <KJ|U0/jGd
} ^u2x26].
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