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)); RlU;v2Kch
} B{;11u
for(int i=0;i<nEndPos.length-1;i++) :-$cdZ3E
{ 2IKxh
nEndPos = nStartPos[i+1]; tDEXm^B2Sv
} 9cVn>Fb
nEndPos[nEndPos.length-1] = nFileLength; EW ~*@H
} fB_4f{E
} V/`#B$6
l{nB.m2
`x2fp6
//启动子线程 qnabwF
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ^?E^']H)5u
for(int i=0;i<nStartPos.length;i++) '&RZ3@}+
{ B1x'5S;Bq
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), {'h)
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), c zZrP"
nStartPos,nEndPos,i); I h5/=_n
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); $|>6z_3%
fileSplitterFetch.start(); 5OPS&:
} ?+bTPl;%'
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), | \AbL!u
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 7J0 ^N7"o
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", !8wZw68"
nEndPos = " + nFileLength); yonJd
// fileSplitterFetch[nPos.length-1].start(); dD[v=Z_
!}iLO0
`DI{wqV9
//等待子线程结束 <FXQxM5"
//int count = 0; g ^D)x[
//是否结束while循环 ;~}-AI-
boolean breakWhile = false; :X3rd|;kc
\%w7D6dEZ
^ze@#Cp
while(!bStop) j'G"ZPw1
{ r$b:1C~
write_nPos(); !JT<(I2
Utility.sleep(500); 9QX&7cs&[
breakWhile = true; ~z\pI|DQ
wlm3~B\64
/IGrp.}
for(int i=0;i<nStartPos.length;i++) A>qd2
{ 1gF*Mf_7
if(!fileSplitterFetch.bDownOver) M3hy5j(b
{ 0|WOReskK
breakWhile = false; 3c1o,2
break; 2z.k)Qx!Z
} ^JYF1
} #nU@hOfg
if(breakWhile) gg lNpzj
break; ~J8cS
$=\oJ-(!@S
W)6U6
//count++; OU0xZ=G
//if(count>4) d/0/$Bz}P
// siteStop(); X !&"&n
} b|X>3(
y}(_SU
FiV^n6-F`
System.err.println("文件下载结束！"); >GdLEE'w
} \_iH4<#>
catch(Exception e){e.printStackTrace ();} 7VEt4
} 5O;/ lX!u
[i,5>YIk
yrxx+z|wR
//获得文件长度 0hHIz4(
public long getFileSize() m _t(rn~f6
{ |_Naun=+~
int nFileLength = -1; o'x_g^ Y
try{ nr'YWW
URL url = new URL(siteInfoBean.getSSiteURL()); >i><s>=I`
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); "wc`fg"3
httpConnection.setRequestProperty("User-Agent","NetFox"); +^^S'mP8
b&hF')_UOz
]pM5?^<~
int responseCode=httpConnection.getResponseCode(); "k>{b:R|
if(responseCode>=400) S*~Na]nS0
{ ]1/W8z%
processErrorCode(responseCode); 4aIlzaA
return -2; //-2 represent access is error |R_xY=z?
} Vp- n(Z
6E*Zj1KX
3L 1lq .
String sHeader; )w}*PL
e3HF"v]2!
fzGZ:L
for(int i=1;;i++) !5g)3St
{ d\1:1ucV
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); j`LT`p"9S
//Utility.log(in.readLine()); |Oj,S|Z:
sHeader=httpConnection.getHeaderFieldKey(i); t<KEx^gb
if(sHeader!=null) &?`d8\z
{ ; @[.$Q@I
if(sHeader.equals("Content-Length")) (&N$W&
{ ,b2O^tJF#
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); P:zEx]Y%
break; 1*c0\:BQ;z
} TkoCyD9
} Y(Z(dV!Po
else rRA_'t;uK
break; nU">> 1!U
} d-A%ZAkE]
} >mGGJvTx
catch(IOException e){e.printStackTrace ();} `Tm8TZd66
catch(Exception e){e.printStackTrace ();} zm_hLk
g,z&{pZch
I'6ed`|
Utility.log(nFileLength); \nWzn4f
hg86#jq%
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return nFileLength; Is,*qrl :
} eBLHT
<O`q3u'l
TZ[Fu{gZ
//保存下载信息（文件指针位置） c'wU O3S
private void write_nPos() U4mh!
{ duiKFNYN
try{ 'nmYB:&!
output = new DataOutputStream(new FileOutputStream(tmpFile)); *}Ae9
output.writeInt(nStartPos.length); +Fy-~Mq
for(int i=0;i<nStartPos.length;i++) Eb{4.17b
{ LcQ\?]w`]
// output.writeLong(nPos); ND99g
output.writeLong(fileSplitterFetch.nStartPos); `6l24_eKf
output.writeLong(fileSplitterFetch.nEndPos); se*pkgWbz
} .+yJh
output.close(); LeRh(a`=$
} lw/ m0}it
catch(IOException e){e.printStackTrace ();} 4*ty&s=5OJ
catch(Exception e){e.printStackTrace ();} c,u$tnE)
} Liz6ob
8xGkh?%
"78cl*sD
//读取保存的下载信息（文件指针位置） L>R!A3G1
private void read_nPos() 1{uDHB
{ b}q(YgH<
try{ V.OoZGE>]
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Nr*ibtz|D
int nCount = input.readInt(); p%M(G#gOgP
nStartPos = new long[nCount]; zs]>XO~Jg
nEndPos = new long[nCount]; wxr}*Z:ZMa
for(int i=0;i<nStartPos.length;i++) qLktMp_
{ 6I6ZVSxb
nStartPos = input.readLong(); zDQ\PZ~
nEndPos = input.readLong(); b^=8%~?%4
} #ui%=ja[:~
input.close(); `\/Wah}I
} jWb\"0)
catch(IOException e){e.printStackTrace ();} %/,Uk+3p
catch(Exception e){e.printStackTrace ();} 4VL!U?dk
} Se]t;7j
V[2<ha[n>
14)kKWG
private void processErrorCode(int nErrorCode) U:\oGa84A
{ -<VF6k<
System.err.println("Error Code : " + nErrorCode); u BW
} Ml_:Q]kl^
P^{`d_[K%
?2bE=|
//停止文件下载 :-jP8X
public void siteStop() mm9S#Ya
{ EPUJa~4
bStop = true; [7t0[U~3?
for(int i=0;i<nStartPos.length;i++) <a/ZOuBzZ
fileSplitterFetch.splitterStop(); 3kzGL
l#(g&x6J
~'YSVx& )
} I]S(tx!
} looPO:bo^
//负责部分文件的抓取 U=*q;$L#
**FileSplitterFetch.java 0O9 Lg}
*/ :ftyNaq'
package NetFox; L[9+xK^g
Z~R/p;@
ki/Lf4
import java.io.*; (fjXp75
import java.net.*; :\HN?_?{4
9%hB
-T="Ml&
public class FileSplitterFetch extends Thread { *{n,4d\..
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(h(ZL9!
String sURL; //File URL sT8kVN|Uv
long nStartPos; //File Snippet Start Position %Zi,nHg8
long nEndPos; //File Snippet End Position mjJlXA
int nThreadID; //Thread's ID SEn8t"n
boolean bDownOver = false; //Downing is over a*ixs'MJ
boolean bStop = false; //Stop identical T?$?5
FileAccessI fileAccessI = null; //File Access interface Z-r0 D
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ViC76aJ
{ (TK cSVR
this.sURL = sURL; G37L 9IG-M
this.nStartPos = nStart; R5YtCw]i=
this.nEndPos = nEnd; Q0cf]
nThreadID = id; xuC6EK+
fileAccessI = new FileAccessI(sName,nStartPos);//定位 G`<1>%"F
} 53#5p;k
L?5t<`#lw
iO#xIl<
public void run() a\.?{/
{ ="*C&wB^
while(nStartPos < nEndPos && !bStop) \fGYJ37
{ JSP8Lu"n
>L3p qK
7PPsEU:rf
try{ &5CeRx7%
URL url = new URL(sURL); ]$X=~>w
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); . *+7xL
httpConnection.setRequestProperty("User-Agent","NetFox"); pc(9(. |
String sProperty = "bytes="+nStartPos+"-"; FP cvkXQD
httpConnection.setRequestProperty("RANGE",sProperty); J-,X0v"
Utility.log(sProperty); J!qEj{
)FiU1E
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InputStream input = httpConnection.getInputStream(); rs KE
//logResponseHead(httpConnection); A^jm<~
HAOrwJFqU
0R{R=r]
byte[] b = new byte[1024]; (W6\%H2u
int nRead; J~ rC
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) O?<_,-.
{ {twf7.eY
nStartPos += fileAccessI.write(b,0,nRead); v*p)"J *
//if(nThreadID == 1) tz>X'L
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 0{@Ovc
} y")>"8H
G&B}jj
y3$\ m
Utility.log("Thread " + nThreadID + " is over!"); r]vBr^kq
bDownOver = true; DD3yl\#,
//nPos = fileAccessI.write (b,0,nRead); Fgq*3t
} $e,!fB;B
catch(Exception e){e.printStackTrace ();} x=<>%m5R
} sm <kb@g
} KPK!'4,cu
3om7LqcRo
biuo.OG]
//打印回应的头信息 RB@gSHOc?
public void logResponseHead(HttpURLConnection con) @k;3$
{ DxG'/5jQ[
for(int i=1;;i++) aYX'&k `
{ ?-p aM5Q+
String header=con.getHeaderFieldKey(i); "K=)J'/n
if(header!=null) bpCe&*\6K
//responseHeaders.put(header,httpConnection.getHeaderField(header)); rW .0_*
Utility.log(header+" : "+con.getHeaderField(header)); 6:X\vw
else iC\=U
break; lJ2/xE]
} S;kc{?
} KAaeaiD
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public void splitterStop() !KW)*
{ ImW~Jy
bStop = true; UeTp,
} ?=Qg
clV/i&]Qa
k18V4ATE]
} vK/Z9wR*05
WWzns[$f
oMf h|B
/* )^xmy6k
**FileAccess.java 1a4$. {
*//文件访问(定位，写) !0_Y@>2
package NetFox; q&x#S_!
import java.io.*; JB}h}nb
WWs>@lCK
mjc:0hH
public class FileAccessI implements Serializable{ 09i[2n;O
7guxkN#
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Unk+@$E&
RandomAccessFile oSavedFile; &?pAt30K:
long nPos; bm|8Jbsb&
qa#F}aGd
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public FileAccessI() throws IOException T!$HVHh&,}
{ 2?&ptN)`N
this("",0); `84yGXLK
} x$4'a~E
XAkl,Y
)^3655mb
public FileAccessI(String sName,long nPos) throws IOException o*8 pM`uw
{ W{2y*yqY
oSavedFile = new RandomAccessFile(sName,"rw"); .w"O/6."
this.nPos = nPos; breVTY7 S
oSavedFile.seek(nPos); DSa92:M}
} Z0^do
>eI(M $
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public synchronized int write(byte[] b,int nStart,int nLen) Q4 S8NqE
{ (CwaOm{g
int n = -1; an@Ue7
try{ 4\iQ%fb
oSavedFile.write(b,nStart,nLen); ;bmd<1
n = nLen; J>&GP#7}
} 4(]('[M
catch(IOException e) HX^ P9jXT
{ =25"qJr
e.printStackTrace (); )Qp?LECrt
} "[,XS`
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return n; ^hJ,1{o
} efm<bJB2
0cVXUTJ|W
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} S6I8zk)Z4
n_Dhq(.
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/* cgAcAcmY
**SiteInfoBean.java }P#gXG
*/ DO; 2)ZQ%
package NetFox; L"0L_G
Fh;(1X75I
'-_PO|}
public class SiteInfoBean { ,y @3'~
eA_4,"{
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private String sSiteURL; //Site's URL 4B 6Aw?
private String sFilePath; //Saved File's Path .Dz /MSl
private String sFileName; //Saved File's Name 8X5XwFf}
private int nSplitter; //Count of Splited Downloading File #(G&%I A|;
^TGHWCK!t
lw{|~m5`
public SiteInfoBean() c+c^F/
{//nSplitter的缺省值为5 !h~\YE)
//default value of nSplitter is 5 {,ljIhc,
this("","","",5); XhiC'.B_
} kzT'
*G4;
0v?,:]A0E
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ,v+SD\7|
{ gf@Dy6<
sSiteURL= sURL; {cFei3'q
sFilePath = sPath; dLq!t@?iu>
sFileName = sName; TMrmyvv
this.nSplitter = nSpiltter; '}=M~
5s9~rm
qZ.\GHS
} 9"e!0Q40
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zc#`qa:0
public String getSSiteURL() ]SI`fja/
{ ]Yy Sf
return sSiteURL; P!/8
} uQlVzN.?
Fk\xq`3'c
QK\z-'&n
public void setSSiteURL(String value) *gnL0\*
{ P'+*d#*S
sSiteURL = value; ?5D7n"jY
} >JhQ=j
6{6tg>|L)
%F7k| Na
public String getSFilePath() Yp8$0KK
{ FpEdwzBb<
return sFilePath; ur|2FS7
} hI yfF
rBL)ct
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public void setSFilePath(String value) /[p4. FL
{ ?w+T_EH
sFilePath = value; u|C9[(
} f]EHDcC3X
sQkP@Y
[,c>-jA5
public String getSFileName() NTC,Vr\A
{ S/4kfsN
return sFileName; !PgYn
} d@<XR~);
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R*U>T$
public void setSFileName(String value) RK,~mXA
{ Z7Kc`9.0|
sFileName = value; 5R4 dN=L*1
} Gs%kqD{=
iR9iI!+;N
B0:O]Ax6.^
public int getNSplitter() KLk37IY2\
{ JGtdbD?Fw
return nSplitter; 'oTF$3n
} Y<B| e91C
^6=nL<L
B\6\QQ;rUo
public void setNSplitter(int nCount) hE;
{ 5Z@Q^
nSplitter = nCount; !@Ox%vK
} B`vV[w?
} tNjrd}8s
1@am'#<
/N$T[
/* rO C~U85
**Utility.java Dbgw)n*2
*/ (b(iL\B$D=
package NetFox; Ne=D$o
=hA/;
i}!CY@sW
public class Utility { qU"+0t4
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76 y}1aa
public Utility() M8h9i2
{ c9Cp!.#*E
*ce h ]v
`0L!F"W
} DV.m({?
@~"0|,6VC
//线程睡眠 /as1
public static void sleep(int nSecond) P^ a$?
{ yJ^}uw
try{ Q$3%aR-2
Thread.sleep(nSecond); P%1s6fjU
} 5n_<)Ycj
catch(Exception e) YcIk{_N3
{ /t816,i
e.printStackTrace (); t({:TQ
} ]1klfp,`
} NJ|8##Z>
B$fL);l-
//日志 1e}wDMU(
public static void log(String sMsg) V< J~:b1V
{ k}/0B
System.err.println(sMsg); ,ujoGSx}
} lOVsp#
(mv8_~F0
Z yIn>]{
public static void log(int sMsg) lO:[^l?F
{ /Qbt
System.err.println(sMsg); F77~156
} eOS#@6U=u
} N/Z<v* i"
g4Tc (k#
+YP,LDJ!v
/* NO'-HKHj
**TestMethod.java [~x Ql
*/ Oq[tgmf
package NetFox; CYz]tv}g:
4/$]wK`
3^8%/5$v
public class TestMethod { CT/`Kg_
P>:"\I[
`/"TYR%
public TestMethod() Jcm"i~
{ ///xx/weblogic60b2_win.exe #*5A]"k
try{ n:HF&j4C,
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); gQ&FO~cr
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); p!173y,nL
SiteFileFetch fileFetch = new SiteFileFetch(bean); @zE_fL
fileFetch.start(); CB|Z~_Bm
} gVA$P
catch(Exception e){e.printStackTrace ();} KN5.2pp
[}.OlR3)
]GRPxh
} nNf/$h#;O
;|66AIwDe
68d(6?OgW
public static void main(String[] args) \!`*F:7]-
{ |NL$? %I
new TestMethod(); XBCz\f
} \ 3ha
} {,,w5/k^
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