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)); OhA^UP01-
} tEi@p;Z>
for(int i=0;i<nEndPos.length-1;i++) Ktg&G<%J0
{ 1G e)p4
nEndPos = nStartPos[i+1]; sRkz WMl
} o'x_g^ Y
nEndPos[nEndPos.length-1] = nFileLength; }M"-5K}
} >i><s>=I`
} "wc`fg"3
[15hci+-
b&hF')_UOz
//启动子线程 UiGUaBmF*
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ~G|{qVO7A
for(int i=0;i<nStartPos.length;i++) >#${.+y
{ 9*GL@_c
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), sqq/b9 uL/
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), &(z8GYBr
nStartPos,nEndPos,i); x9XGCr
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); uAPLT~
fileSplitterFetch.start(); 1A,4Aw<
} hEdo,gF*
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 18[?dV
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Nlf&]^4(0
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", [)b/uR
nEndPos = " + nFileLength); [T$$od[.
// fileSplitterFetch[nPos.length-1].start(); ve64-D
PuUon6bZ
MkluK=$
//等待子线程结束 _umO)]Si
//int count = 0; 0{{p.n8a~
//是否结束while循环 &gKP6ANx2
boolean breakWhile = false; O"2wV +9
.R<s<]
b&|YQW}~
while(!bStop) hc@;}a\Y
{ ey9fbS ^I
write_nPos(); !0d9<SVC
Utility.sleep(500); tZJ 9}\r
breakWhile = true; 0qaG#&!
z-{"pI
W~W?<%@
for(int i=0;i<nStartPos.length;i++) Y/:Q|HnXQ
{ T$>=+U
if(!fileSplitterFetch.bDownOver) K|Ij71
{ 6):sO/es
breakWhile = false; \8C*O{w
break; egIS rmL+X
} +Qb2LR
} \fQgiX
if(breakWhile) 1W6n[Xg
break; r*
R- ?0k:
%_i0go,^
//count++; OFPd6,(E
//if(count>4) ?tal/uC
// siteStop(); `rOe5Zp$
} -mWw.SfEZ
<R]Wy}2-
$F /p8AraK
System.err.println("文件下载结束！"); Z{R=h7P
} Do{*cSd
catch(Exception e){e.printStackTrace ();} TF([yZO'
} :67d>wb
(cqA^.Td
RIVN>G[;L
//获得文件长度 \:f}X?:
public long getFileSize() 5]2!Bb6>
{ hc4`'r;
int nFileLength = -1; K\%"RgF@&
try{ XTn{1[.O
URL url = new URL(siteInfoBean.getSSiteURL()); ogh2kht
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); [/2@=Uh-
httpConnection.setRequestProperty("User-Agent","NetFox"); 0,i+
1<Ztk;$A
[]]LyWk
int responseCode=httpConnection.getResponseCode(); hzf}_1
if(responseCode>=400) , K"2tb
{ S)AE
processErrorCode(responseCode); eJwii
return -2; //-2 represent access is error :XZJxgx
} KG./<"c
<?`e9o
qo&SJDG
String sHeader; h19.b:JT
",,qFM!
khO<Z^wi[
for(int i=1;;i++) "N[gMp6U
{ xBx?>nN
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); f"}14V
//Utility.log(in.readLine()); <3]/ms
sHeader=httpConnection.getHeaderFieldKey(i); b ffml
if(sHeader!=null) >Gu>T\jpe.
{ d ;Gm{g#
if(sHeader.equals("Content-Length")) V1+o3g{}
{ Yhv`IV-s
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); rq|czQ
break; Z#E#P<&d
} TlZlE^EE<
} 6`PGV+3j
else {10+(Vl
break; 7$!Bq#
} 5'}!v
} fqp7a1qQl
catch(IOException e){e.printStackTrace ();} FK,r<+h
catch(Exception e){e.printStackTrace ();} Yv`1ySR
]H@uuPT!
98%a)s)(a
Utility.log(nFileLength); Q,LWZw~"
L[9+xK^g
f>JzG,-
return nFileLength; ki/Lf4
} fVe-esAw
:\HN?_?{4
9%hB
//保存下载信息（文件指针位置） -T="Ml&
private void write_nPos() *{n,4d\..
{ fJN9+l
try{ (h(ZL9!
output = new DataOutputStream(new FileOutputStream(tmpFile)); q|Tk+JH{5
output.writeInt(nStartPos.length); %Zi,nHg8
for(int i=0;i<nStartPos.length;i++) |D_n4#X7u
{ SEn8t"n
// output.writeLong(nPos); <PA$hTYM
output.writeLong(fileSplitterFetch.nStartPos); T?$?5
output.writeLong(fileSplitterFetch.nEndPos); 0|3B8m
} }lbx
output.close(); &[\arwe)
} N pIlQaMo4
catch(IOException e){e.printStackTrace ();} Fu=VY{U4
catch(Exception e){e.printStackTrace ();} bsS|!KT
} E52:c]<'m
UgBY ){<
,}xC) >
//读取保存的下载信息（文件指针位置） J'&?=|
private void read_nPos() ^|axtVhMO
{ X=RmCc$:
try{ \>CBam8d
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); wB0WR
int nCount = input.readInt(); rEyMSLN
nStartPos = new long[nCount]; a\.?{/
nEndPos = new long[nCount]; z:q'?{`I
for(int i=0;i<nStartPos.length;i++) \fGYJ37
{ 9#ay(g
nStartPos = input.readLong(); >L3p qK
nEndPos = input.readLong(); S6Xw+W02
} 2Uw}'J_N
input.close(); { l~T~3/i
} pc(9(. |
catch(IOException e){e.printStackTrace ();} cF6@.)
catch(Exception e){e.printStackTrace ();} (>% Vj
} (?=(eo<N
ku8Z;ONeH
s`#j8>`M
private void processErrorCode(int nErrorCode) qdnNapWnc
{ nFOG=>c}
System.err.println("Error Code : " + nErrorCode); ~wV98u-N
} vTa23YDW
zL=I-fVq
I(eR3d:
//停止文件下载 5_T>HHR6
public void siteStop() 2/NWWoKw
{ -CNv=vj 3
bStop = true; S 2` ;7
for(int i=0;i<nStartPos.length;i++) S`PSFetC
fileSplitterFetch.splitterStop(); Nr7.BDA
81 Not
oieLh"$
} R1rfp;
} X%qR6mMfT7
//负责部分文件的抓取 x{w?X.Nt
**FileSplitterFetch.java ph.:~n>z
*/ $BN+SD!
package NetFox; (9QRg;
;(Va_
w9}IM149
import java.io.*; F>nrV
import java.net.*; 3m9E2R,
.}opmI
}Qu 7o
public class FileSplitterFetch extends Thread { k3eN;3#&
zm.sX~j
/ S^m!{
String sURL; //File URL J*k=|+[
long nStartPos; //File Snippet Start Position JVYYwA^.
long nEndPos; //File Snippet End Position c_=zd6 b$S
int nThreadID; //Thread's ID %&S]cEw
boolean bDownOver = false; //Downing is over ~DS9{Y
boolean bStop = false; //Stop identical =hb87g.
FileAccessI fileAccessI = null; //File Access interface atnbM:t
%zVv3p:
y9mZQq
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException *m/u3.\
{ PhdL@Mr
this.sURL = sURL; 4&WzGnK
this.nStartPos = nStart; Y&%0 eI!
this.nEndPos = nEnd; UYLI>XSd
nThreadID = id; dXN&<Q,
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ?XrTZ{5'
} {x$#5PW
7i\[Q8f
5Wjp_^!e
public void run() uU"s50m
{ 6!m#_z8qG3
while(nStartPos < nEndPos && !bStop) p{GDW_
{ ~UFsiVpL
mjc:0hH
09i[2n;O
try{ [^P2Kn
URL url = new URL(sURL); iIRigW
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !7|9r$
httpConnection.setRequestProperty("User-Agent","NetFox"); BE;iC.rW
String sProperty = "bytes="+nStartPos+"-"; #J9XcD{1
httpConnection.setRequestProperty("RANGE",sProperty); dRC+|^rSC
Utility.log(sProperty); uQ)]g
jl7-"V>j?;
SpQ6A]M gm
InputStream input = httpConnection.getInputStream(); WJ,ON-v
//logResponseHead(httpConnection); J?DyTs3Z
)8PL7P84
9a,CiH%@
byte[] b = new byte[1024]; VUhu"h@w%
int nRead; b&&'b)
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) w%na n=
{ yFv3>\
nStartPos += fileAccessI.write(b,0,nRead); Tl-B[CT
//if(nThreadID == 1) .v!e=i}.
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); z81!F'x;
} ,bg#pG!x Q
]>j_ Y,
-': tpJk
Utility.log("Thread " + nThreadID + " is over!"); BGOI
bDownOver = true; YkbLf#2AE|
//nPos = fileAccessI.write (b,0,nRead); u{^Kyo#v
} H2-(
catch(Exception e){e.printStackTrace ();} 4(]('[M
} HX^ P9jXT
} =25"qJr
v-@@>?W-
j$Co-b1
//打印回应的头信息 p `Z7VG
public void logResponseHead(HttpURLConnection con) 21Opx~T3
{ ^hJ,1{o
for(int i=1;;i++) efm<bJB2
{ 0cVXUTJ|W
String header=con.getHeaderFieldKey(i); =$J2
if(header!=null) H|?`n uiD
//responseHeaders.put(header,httpConnection.getHeaderField(header)); P@ u%{
Utility.log(header+" : "+con.getHeaderField(header)); ~{{:-XkVB
else qlP=Y .H
break; s:{%1/
} *a4eL [
} U^I'X7`r
fx5vaM!
pj`-T"Q
public void splitterStop() pDT6>2t
{ |\ L2q/u
bStop = true; j=LF1dG"
} R8)"M(u=l
,\IZ/1
(Nf.a4O
} it@s(1EO#
c{q`uI;O
W1z5|-T
/* =nl,5^
**FileAccess.java fq'Of wT
*//文件访问(定位，写) ~1oD7=WN
package NetFox; C_/oORvK
import java.io.*; a6OT2B
A |B](MW%O
3lqhjA
public class FileAccessI implements Serializable{ X"sN~Q.0
TM;)[R@
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 WfVie6
RandomAccessFile oSavedFile; Z^3Risi
long nPos; .nN7*))Fj
OWzIea@
82<!b]^1
public FileAccessI() throws IOException pY@+.V`a
{ ;f?bb*1
this("",0); kaLRI|hC
} L.'N'-BV
zc#`qa:0
]SI`fja/
public FileAccessI(String sName,long nPos) throws IOException Q2o:wXvj
{ Nx"?'-3Hm
oSavedFile = new RandomAccessFile(sName,"rw"); RPu-E9g@
this.nPos = nPos; `:&{/|uP7
oSavedFile.seek(nPos); YH9BJ
} pWqahrWh
SzDi=lY
*SZ<ori
public synchronized int write(byte[] b,int nStart,int nLen) xnTky1zq
{ N Jf''e3
int n = -1; *!/9?M{p
try{ ScD9Ct*):C
oSavedFile.write(b,nStart,nLen); n9%rjS$
n = nLen; -Y6JU
} ,yoT3_%P
catch(IOException e) 1,E/So
{ h ? M0@Z
e.printStackTrace (); B.o&%5dG
} a)e2WgVB/E
M:~#"lfK
]KmYPrCl0
return n; B4?P"|
} K"D9.%7
>_o_&;=`v
bF.Aj8ZQ
} qr*/}F6
'#fj)
:MpCj<<[
/* 31}6dg8?n
**SiteInfoBean.java _Cxs"to
*/ anbr3L[!
package NetFox; ZO,]h9?4
0bor/FU-d
-(jcsqDk
public class SiteInfoBean { $_y"P
$I'ES#8P6
u=4Rn
private String sSiteURL; //Site's URL V\_ &2',t
private String sFilePath; //Saved File's Path /#a$4 }2L
private String sFileName; //Saved File's Name n1QO/1} :
private int nSplitter; //Count of Splited Downloading File >\e11OU0Gy
>y?$aJ8ZV
<K43f#%
public SiteInfoBean() Bn.8wMB
{//nSplitter的缺省值为5 /1Eg6hf9B
//default value of nSplitter is 5 #>0nNR[$Y
this("","","",5); }\@*A1*X2
} ~Oq(JM $M
'&`Zy pq
5b&'gd^d
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 30<^0J.1
{ bV"0}|A~K
sSiteURL= sURL; :KQ<rLd
sFilePath = sPath; uwbj`lpf
sFileName = sName; 7"gy\_M
this.nSplitter = nSpiltter; t((0]j^
vm(% u!_P
Co'dZd(
} A9"ho}<
-kJ`gdS
8?PNyO-Wt5
public String getSSiteURL() gw H6r3=y(
{ =0Nd\
return sSiteURL; 'b-}KDP
} X0m\
EfOJ%Xr[,l
1&dWt_\
public void setSSiteURL(String value) m^wYRA.
{ qwN-VCj
sSiteURL = value; oOuWgr]0
} u~K4fP
7&X^y+bMe6
9N9;EY-U
public String getSFilePath() =KX:&GU
{ NK#f Gz*,(
return sFilePath; k?_Miqr
} hE>Mo$Q(
|[*b[O 1W
B$fL);l-
public void setSFilePath(String value) /vBpRm
{ 6JJ%`Uojh
sFilePath = value; !4|7U\;
} HH>]"mv
/@0wbA
.6r&<*
public String getSFileName() P5[.2y_qM
{ o0AREZ+I
return sFileName; rt f}4.
} 291v R]
'E6)6N
myH#.$=A
public void setSFileName(String value) !bQ5CB
{ zE<}_nA
sFileName = value; MgA6/k
} 8}4V$b`Z
9]l7j\L
m#Rll[
public int getNSplitter() (}'0K?
{ {4 *ob@w*
return nSplitter; B&"fPi
} fk=_ Y
6%:N^B=%}
=YI<L8@g~
public void setNSplitter(int nCount) _Nw-|N.
{ Zx3m$.8
nSplitter = nCount; p!173y,nL
} 9kTU|py
} SFTThM]8M1
HuG|BjP
H$Q_K<V
/* KN5.2pp
**Utility.java {eS!cZJ
*/ oveW)~4
package NetFox; nNf/$h#;O
o: qB#8X
\T>f+0=4
public class Utility { :h"Y>1P
gJ:Z7b
jytfGE:
public Utility() \ 3ha
{ {,,w5/k^
6:@tHUm
f~9ADb
} @va6,^)
7|*|xLrVY
//线程睡眠 ]^R;3kU4Q
public static void sleep(int nSecond) D[ny%9 :
{ "J$vt`
try{ wtaeF+u-R-
Thread.sleep(nSecond); dnH?@K
} .Q4EmpByCg
catch(Exception e) jf@#&%AC9
{ FK0nQ{uB"
e.printStackTrace (); RaKL KZn
} VcA87*pel
} YaDr6)
Sky!ZN'I
//日志 Xrc0RWXB8
public static void log(String sMsg) .pK_j~}P
{ xrp%b1Sy
System.err.println(sMsg); 5)nm6sf
} 1:XT r
$yBU ,lu}
+!CG'qyN>
public static void log(int sMsg) c[f
{ ^|(F|Z
System.err.println(sMsg); XzkC ]e'
} UJ2Tj+
} g#W)EXUR
v~9PS2
5'Y @c
/* *ix&"|h
**TestMethod.java @ITJ}e4
*/ vA*!82
package NetFox; fU8 &fo%ER
hVd% jU:
{b}Ri&oEOH
public class TestMethod { ^F/N-!}q
+<(N]w*
D`V03}\-
public TestMethod() k& 2U&
{ ///xx/weblogic60b2_win.exe "o+< \B~
try{ QQj)"XJ29
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ?v\A&d
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); IR(qjm\V
SiteFileFetch fileFetch = new SiteFileFetch(bean); Lp.,:z7
fileFetch.start(); $<OX\f%
} bODCC5yL
catch(Exception e){e.printStackTrace ();} [8v v[n/
sFsp`kf
=]K;"
} @Xts}(L
P{h;2b{
An{`'U(l
public static void main(String[] args) qk<(iVUO
{ kFg@|#0v9
new TestMethod(); gG!L#J?
} kl,I.2-
} `qbf_;\
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