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)); tE(x8>5A:
} E 7;KG^
for(int i=0;i<nEndPos.length-1;i++) :}+U?8/"7
{ 31w?bx !Pp
nEndPos = nStartPos[i+1]; yc_(L-'n
} %/1`"M5ko
nEndPos[nEndPos.length-1] = nFileLength; h+R}O9BD
} i:qc2#O:J
} 0}Kl47}aD
u'yePJTE
[9[tn-
//启动子线程 |pq z(j7
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; \@MGOaR]
for(int i=0;i<nStartPos.length;i++) +\"@2mOH{+
{ G U0zlG] C
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Y49kq}
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Vn=J$Uv0
nStartPos,nEndPos,i); |I)MsNF
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 0t/S_Q
fileSplitterFetch.start(); 7:jSP$
} -S)HB$8
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), #uuwzE*M_
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); {7Dc(gNS
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", b[e+(X
nEndPos = " + nFileLength); pC_2_,6$
// fileSplitterFetch[nPos.length-1].start(); "O9uz$
WVJN6YNd V
,i>5\Yl%
//等待子线程结束 rf1-E57#
//int count = 0; !6f#OAP\
//是否结束while循环 KhXW5hS1
boolean breakWhile = false; D2>=^WP6+
w`F}3zm
&&_W,id`
while(!bStop) A' dt WD
{ J*a`qU
write_nPos(); 4A|5eg9N
Utility.sleep(500); >jN)9}3>-#
breakWhile = true; i`Lt=)@&
4;w_o9o
mR8&9]g&
for(int i=0;i<nStartPos.length;i++) -_b}b)2iYN
{ BO/2kL8*
if(!fileSplitterFetch.bDownOver) 0DS<(
{ -2% []
breakWhile = false; O23f\pm&
break; bG2!5m4L
} ymr-kB
} olK%TM[Y
if(breakWhile) b*?="%eE(
break; RX7,z.9@'O
TyGXDU
|`:Uww+3
//count++; XXxX;xz$
//if(count>4) |}'}TYX0:
// siteStop(); TtkB
} E*rDwTd
T'fE4}rY
!C#q
System.err.println("文件下载结束！"); 8h;1(S)*Z
} S`"IM?
catch(Exception e){e.printStackTrace ();} X} 8rrC=
} >MiA|N=
*K-,<hJ#L
rpDH>Hzq
//获得文件长度 D&Ngg)_Mq
public long getFileSize() F?5kl/("
{ 3smcCQA%
int nFileLength = -1; Z#"6&kv
try{ .`xcR]PQ
URL url = new URL(siteInfoBean.getSSiteURL()); >q[Elz=dI
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); P%%Cd
httpConnection.setRequestProperty("User-Agent","NetFox"); #l8CUg~Uj
9Tjvc!4_b
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int responseCode=httpConnection.getResponseCode(); ];zi3oS^
if(responseCode>=400) o8Q(,P
{ !7^fji
processErrorCode(responseCode); i"sVk8+o!
return -2; //-2 represent access is error C.pNDpx-
} "6Ly?'HK
\*d@_oQ$
}JrM!'
String sHeader; BD,~M*%z
{7B$%G'
OO53U=NU
for(int i=1;;i++) gt{ei)2b
{ TZ-n)rC)v
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); B\Rq0N]' M
//Utility.log(in.readLine()); ]'2p"A0U
sHeader=httpConnection.getHeaderFieldKey(i); .+{nfmc,c
if(sHeader!=null) v2rXuo
{ <f{m=Dc
if(sHeader.equals("Content-Length")) w;r-TLf
{ ?ew^%1!W.
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); f,`FbT
break; 3cQTl5,
} CaZEU(i
} C+-~Gmrb(7
else H-7*)D
break; 6Y\9h)1Jo
} Njz,y}\
} Oh<Z0M)
catch(IOException e){e.printStackTrace ();} v8-F;>H
catch(Exception e){e.printStackTrace ();} _qJ[~'m<^C
2ORWdR.b
oBKZ$&_h
Utility.log(nFileLength); 49HtI9@
Q.M3rRh
K& 2p<\2
return nFileLength; tlqDY1
} od?Q&'A
AvP*p{we
$T]1<3\G
//保存下载信息（文件指针位置） I2K52A+
private void write_nPos() HmRwh
{ OXA_E/F
try{ LF*3Iw|v
output = new DataOutputStream(new FileOutputStream(tmpFile)); BniFEW:<
output.writeInt(nStartPos.length); YN"102CK
for(int i=0;i<nStartPos.length;i++) +S0A`rL
{ x1mxM#ql
// output.writeLong(nPos); C2ToT\^
output.writeLong(fileSplitterFetch.nStartPos); dpJi5fN
output.writeLong(fileSplitterFetch.nEndPos); Mr/^V,rA
} >G/>:wwSP.
output.close(); MH{vFA4:,
} mj5A*%"W
catch(IOException e){e.printStackTrace ();} D1#E&4
catch(Exception e){e.printStackTrace ();} ((;9%F:/$
} --",}%-
CcAsJX~_
v+G}n\F
//读取保存的下载信息（文件指针位置） a[Txd=b
private void read_nPos() dA\>z[n=
{ rYN`u
try{ ot(|t4^
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); LUS7-~:F
int nCount = input.readInt(); 90I)"vfW5
nStartPos = new long[nCount]; UY%@i
nEndPos = new long[nCount]; a,&Kvh
for(int i=0;i<nStartPos.length;i++) ~LYKt0/W&
{ gtjgC0
nStartPos = input.readLong(); EsA^P2?_+
nEndPos = input.readLong(); Q7c_;z_
} bp$8hUNYz-
input.close(); alHwN^GhP
} o)S>x0|[
catch(IOException e){e.printStackTrace ();} $V`O%Sz
catch(Exception e){e.printStackTrace ();} Ldir'FW
} JR7~|ov
A[+op'>k
/1n}IRuw
private void processErrorCode(int nErrorCode) sY1@ch"
{ ;M4N=G Wd4
System.err.println("Error Code : " + nErrorCode); y^M'&@F
} Y5ebpw+B-
pok,`yW\
*;"^b\f5_
//停止文件下载 K"-N:OV
public void siteStop() zS?i@e $
{ :CK,(?t
bStop = true; pklcRrx,a
for(int i=0;i<nStartPos.length;i++) )S8q.h
fileSplitterFetch.splitterStop(); 4_r8ynq{z
"NC(^\l/
hw~cS7
} BIV]4vl-&
} K7e<hdP_#
//负责部分文件的抓取 %qja:'k
**FileSplitterFetch.java X<-]./
*/ H,3$TNXy
package NetFox; DgOoEHy[
~Ycz(h'(
F<IqKgGzH
import java.io.*; ]V.9jlXF
import java.net.*; m{+lG*
-6t# ?Dkc'
A=h`Z^8\B
public class FileSplitterFetch extends Thread { (7Y :3
.fD k5uo
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String sURL; //File URL c%uhQ62
long nStartPos; //File Snippet Start Position ' P-K}Y
long nEndPos; //File Snippet End Position 9iS3.LCfX
int nThreadID; //Thread's ID pLyX9C
boolean bDownOver = false; //Downing is over unD8h=Z2
boolean bStop = false; //Stop identical o/=K:5
FileAccessI fileAccessI = null; //File Access interface $I1p"6
\?qXscq
_}JygOew
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException rRC3^X`u
{ X]y3~|K
this.sURL = sURL; rM>&!?y+
this.nStartPos = nStart; ;'J L$=
this.nEndPos = nEnd; /=7|FtB`
nThreadID = id; "#e2"=3*
fileAccessI = new FileAccessI(sName,nStartPos);//定位 XTZWbhNF
} @}fnR(fS
xn}'!S2-b
7Jc=`Zm'
public void run() zWjGGTP~3&
{ 3_Oq4/
while(nStartPos < nEndPos && !bStop) n]8_]0{qi
{ +;;fw |/
EidIi"sr
DlIfr6F
try{ ,LzS"lmmo
URL url = new URL(sURL); 6[qRb+ds
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); N?87Bd
httpConnection.setRequestProperty("User-Agent","NetFox"); n,Ux>L
String sProperty = "bytes="+nStartPos+"-"; *?KQ\ Y
httpConnection.setRequestProperty("RANGE",sProperty); T6phD8#
Utility.log(sProperty); Kh% x
SB \ptF
]]`+aF0
InputStream input = httpConnection.getInputStream(); D 3Int0n
//logResponseHead(httpConnection); 1/1P;8F@G
q{ctHsQ(9
4] DmgOru%
byte[] b = new byte[1024]; mX|AptND
int nRead; ]7xAL7x
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) wz6e^ g
{ [N7[%iQ%
nStartPos += fileAccessI.write(b,0,nRead); AvV.faa
//if(nThreadID == 1) p=405~
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); WtlIrdc
} C<n.C*o
Ho"FB|e
9"V27"s
Utility.log("Thread " + nThreadID + " is over!"); 8E0Rg/DnT
bDownOver = true; KE5f`h
//nPos = fileAccessI.write (b,0,nRead); u $sX6
} 03rZz1
catch(Exception e){e.printStackTrace ();} Y1 -cz:
} qw_qGgbl
} _n{N3da
rp1u
IFv2S|
//打印回应的头信息 }#yRaIp
public void logResponseHead(HttpURLConnection con) 5#2vSq!H
{ 1/#N{rZ
for(int i=1;;i++) eY&UFe
{ ~:+g+Mf~[
String header=con.getHeaderFieldKey(i); E+7S:B
if(header!=null) /H3,v8J@
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 0tsll1
Utility.log(header+" : "+con.getHeaderField(header)); W}.4$f>
else _fa]2I
break; _$=xa6YA
} 1eb1Lvn
} =,0E3:X^
q_oYI3
Ap97Zcw
public void splitterStop() |fzo$Bq
{ w=^*)jZ8
bStop = true; VVe>}
} s;5PHweWf
JL(*peeu3
{1SxM /
} oY0*T9vv+
H%%#^rb^
}"cb^3
/* 2%@j<yS
**FileAccess.java uF^+}Y ZT
*//文件访问(定位，写) Cch1"j<k$
package NetFox; U7ajDw
import java.io.*; B8TI 5mZ4
iK.MC%8?
IGB>8$7
public class FileAccessI implements Serializable{ !HB,{+25
D#k>.)g
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Ws1<Jt3/."
RandomAccessFile oSavedFile; nFB;!r
long nPos; -D(UbkPw
!w/~dy
2{#quXN9
public FileAccessI() throws IOException 6DR8(j)=[%
{ !'[sV^ds
this("",0); M_XZOlW5
} !-;Me&"I=`
h.7 1O"N
MA1,;pv6
public FileAccessI(String sName,long nPos) throws IOException %{Ls$Y)
{ >w*"LZjTTK
oSavedFile = new RandomAccessFile(sName,"rw"); U2Ur N?T
this.nPos = nPos; )FHaJ*&d
oSavedFile.seek(nPos); _6(zG.Fg
} {+r?gJ
\|T0@V
D(r|sw
public synchronized int write(byte[] b,int nStart,int nLen) z2dM*NMK
{ pCC0:
int n = -1; YTGup]d
try{ I &m~ cBj<
oSavedFile.write(b,nStart,nLen); 6l>G>)
n = nLen; 4wBCs0NIm
} MK"Yt<e(o
catch(IOException e) Y{J/Oib
{ "1[N;|xa
e.printStackTrace (); ga,yFw
} +HfjnEbtBs
Nf;vUYP
TvQAy/Y0
return n; <"\K|2Sg
} APLu?wy7s5
+ATN2 o
U2bb|6j
} ,3Wa~\/Q
7)a=B! 8M
A+ f{j
/* *v8 ]99N
**SiteInfoBean.java -J[D:P.Z
*/ a.Mp1W
package NetFox; G;^iwxzhO
60p1.;'/a
v h%\ " h
public class SiteInfoBean { Z4(2&t^
nrf%/L
=LT({8
private String sSiteURL; //Site's URL 2>H\arEstR
private String sFilePath; //Saved File's Path 1fC|_V(0
private String sFileName; //Saved File's Name ZU:gNO0
private int nSplitter; //Count of Splited Downloading File hwXp=not(
o+tY[UX
&bL1G(}
public SiteInfoBean() "@f`O
{//nSplitter的缺省值为5 DL~LSh
//default value of nSplitter is 5 4$|G$h
this("","","",5); @*_K#3
} g`Rs;
ae^xuM?7
c{852R
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Y8AU<M
{ %V+,#
sSiteURL= sURL; Us%VBq
sFilePath = sPath; /g8yc'{p
sFileName = sName; "~+K`*0r8
this.nSplitter = nSpiltter; ~\oJrRYR`
Q!Op^4Jz
9YvMJ
} JTb<uC
@lJGdp
oZ8SEC"]
public String getSSiteURL() AG9U2x
{ BShZ)t
return sSiteURL; U^,ld`
} PD$'xY|1=
|Jq/kmn
>kB?C!\
public void setSSiteURL(String value) QUe.vb^O
{ &R8zuD`#
sSiteURL = value; iD]!PaFD`
} 'kC$R;#\7
b#]in0MT?@
B;-oa;m:E=
public String getSFilePath() '<Vvv^Er
{ gWlmQl
return sFilePath; ]ny(l#Hu:
} t]vz+VQ
L8$7^muad
sVC5<?OW!p
public void setSFilePath(String value) 6#K_Rg>.
{ f{)*"
sFilePath = value; ML'R[~|
} 6-JnT_
iFHVr'Og'
My[L3KTTp
public String getSFileName() 3!}#@<j
{ i$F)h<OU+
return sFileName; $6J5yE
} '2 )d9_ w
c^=:]^
1XZ&X]
public void setSFileName(String value) -p)HH@6a
{ NT-du$!u
sFileName = value; pG4Hy$e
} \Js9U|lY
=X1$K_cN
$DQ -.WI
public int getNSplitter() gz88$BT
{ (&x[>):6?
return nSplitter; I#mT#xs6
} :*8@MjZ4
Z2`e*c-[E
MJD4#G
public void setNSplitter(int nCount) NH?s
{ z;3}GxE-si
nSplitter = nCount; xA-G&oC]<T
} {:rU5 !n
} ())|x[>JS+
oZ=e/\[K
$b8>SSz
/* \twlHj4
**Utility.java ^6`R:SV4Gx
*/ ;m&f Vp
package NetFox; }tJ:-!*2
bVVa5? HP
TJVNR_x
public class Utility { 9XoKOR(
l9<+4rK2
0? l
public Utility() Fq{nc]L6
{ g\^(>Ouc
nyDqR#t
~{N|("nB
} 7i'vAOnw^
dXOjaS# ~
//线程睡眠 P"%/
public static void sleep(int nSecond) [oYe/<3
{ 3O]e
try{ 6znm?s@~
Thread.sleep(nSecond); bc 0|tJc
} P@Qo2zTh%
catch(Exception e) F-ZD6l9O
{ S^n:O
e.printStackTrace (); wF&\@H
} !.F\v.
} Pq`4Y K
GRs;-Jt
//日志 l"vT@g|
public static void log(String sMsg) foN;Q1?lS
{ 't>Qj7vh0
System.err.println(sMsg); iCc\p2p
} pGOS'.K%t8
%+'&$
(_W[~df4
public static void log(int sMsg) D QZS%)
{ !<~Ig/
System.err.println(sMsg); k4`v(au^
} 9np<r82
} u!X2ju<
mq "p"iI
'-*r&:
/* Dg]i};
**TestMethod.java KYeA=
*/ A7sej
package NetFox; &hF>}O
mg3jm
~ PPGU1
public class TestMethod { '}}DPoV
l@GpVdrv
A,iXiDb3pK
public TestMethod() w}E?FEe.
{ ///xx/weblogic60b2_win.exe 1]kk
try{ a`{'u)@
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); qVY\5`f@
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); `C=p7%
SiteFileFetch fileFetch = new SiteFileFetch(bean); m+!%+S1
fileFetch.start(); J^?O]|
} >:K3y$]_
catch(Exception e){e.printStackTrace ();} c1z5t]d
EZ=M^0=Hpf
Oc8+an1m
} "5e]-u'
YvU#)M_h
Oq.) 8E.
public static void main(String[] args) jrW7AT)\
{ x,V_P/?%
new TestMethod(); tF;aB*
} 4$;fj1!Z:
} F )tNA?p)
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