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)); {zcjTJ=Zt8
} .j },
for(int i=0;i<nEndPos.length-1;i++) hB4.tMgZ
{ bBf+z7iyc
nEndPos = nStartPos[i+1]; ;DOz92X94
} TfOZ>uR"g
nEndPos[nEndPos.length-1] = nFileLength; %]` WsG
} pD9c%P
} +J}M$eQ
E7,\s
lPQH_+)Z"
//启动子线程 X,b}d#\
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; go@}r<B$
for(int i=0;i<nStartPos.length;i++) t+VPX2
{ _e W*
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), <f%9w]
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ZL Aq8X
nStartPos,nEndPos,i); 3 ren1
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); U7N<!6
fileSplitterFetch.start(); HD>{UU?
} aap:~F{]X
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), i8]r}a
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); !WmpnPr1
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 9z?F_=PB!
nEndPos = " + nFileLength); @9L9c
// fileSplitterFetch[nPos.length-1].start(); k dqH36&<
@NF8?>!
Z'~5L_.]Ai
//等待子线程结束 &*}S 0
//int count = 0; pfG:PrZ
//是否结束while循环 YY9q'x,w
boolean breakWhile = false; (.cT<(TB
UTz;Sw?~hw
U8dwb
while(!bStop) S70ERRk
{ Co M8
write_nPos(); l40$}!!<
Utility.sleep(500); %2{E'^#)p-
breakWhile = true; GZ%RfKyQ
hf'3yEm
2+'&||h
for(int i=0;i<nStartPos.length;i++) 5"sF#Y&
{ ifkA3]
if(!fileSplitterFetch.bDownOver) 0-FbV,:;
{ _i&\G}mrC
breakWhile = false; mnePm{
break; $T6<9cB@
} >&TktQO_T
} al2v1.Y}
if(breakWhile) >wn&+%i&
break; aCanDMcBnq
,/KHKLY7
]Vubz54
//count++; _^B+Xo@E-
//if(count>4) _R]1J0
// siteStop(); REJ}T:
} .F]6uXd
HZm44y$/
1yo@CaW[\
System.err.println("文件下载结束！"); * PZ=$>r
} # ;9KDt@
catch(Exception e){e.printStackTrace ();} H/b(dbs
} yP@=x!$
k$hWR;U
m=R4A4Y7
//获得文件长度 U>>J_2
public long getFileSize() 1osI~oNZ
{ @ZmpcoDI
int nFileLength = -1; 3|A"CU/z@
try{ )z aMycW
URL url = new URL(siteInfoBean.getSSiteURL()); Vq*p?cF .
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ZE :oK
httpConnection.setRequestProperty("User-Agent","NetFox"); Deam%)bXM]
au8)G_A
2XE4w# [j
int responseCode=httpConnection.getResponseCode(); r"n)I$
if(responseCode>=400) h'bxgIl'`
{ @/9> /?JP
processErrorCode(responseCode); 8E" .y$AW
return -2; //-2 represent access is error a; "+Py
} 27MgwX NQ
~6OdPD
NENbr$,G
String sHeader; {\%x{
GVg0)}
R(:q^?
for(int i=1;;i++) r1[0#5kJ;J
{ 2]7nw1&
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); KT8Fn+
//Utility.log(in.readLine()); 4-TM3Cw`d&
sHeader=httpConnection.getHeaderFieldKey(i); }SYvGp{J,
if(sHeader!=null) 8mV35A7l
{ F4k`x/ak
if(sHeader.equals("Content-Length")) "];19]x6q
{ ie_wJ=s
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); #):FXB$a
break; /g_}5s-Z
} ^v,^.>P
} 0uZHH
else Di&tm1R1
break; 2sXWeiJy;
} )'qZ6%
} s^6S{XJ
catch(IOException e){e.printStackTrace ();} %9M_*]
catch(Exception e){e.printStackTrace ();} WB= gN:?
S]<Hx_[}
.rS0zU
Utility.log(nFileLength); E;+3VJ+F"
<$UY{"?
O|8p #
return nFileLength; Q4UaqiL
} !7_Q_h',
{AB0 PM;-
|=SaI%%Be
//保存下载信息（文件指针位置） ua2SW(C@
private void write_nPos() 1X=}
{ Jo2:0<VL
try{ s]}P jh8
output = new DataOutputStream(new FileOutputStream(tmpFile)); E*CY/F I_
output.writeInt(nStartPos.length); :HwB+Bjy
for(int i=0;i<nStartPos.length;i++) E")82I
{ GU_R6Wt+
// output.writeLong(nPos); -{ZRk[>Z
output.writeLong(fileSplitterFetch.nStartPos); VG)kPKoi
output.writeLong(fileSplitterFetch.nEndPos); .aNy)Yu8
} l2$6ojpo
output.close(); O)W1.]GMbf
} dC)@v]#h
catch(IOException e){e.printStackTrace ();} GUMO;rZs
catch(Exception e){e.printStackTrace ();} ?-6oh~W<
} z0c_&@uj*
8)T.[AP
>R :Bkf-
//读取保存的下载信息（文件指针位置） O[$&]>x]]
private void read_nPos() './s'!Lj
{ (A?/D!y
try{ wVp
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); edA.Va|0
int nCount = input.readInt(); :dB6/@fW
nStartPos = new long[nCount]; ZXp=QH+f
nEndPos = new long[nCount]; 40mgB4I
for(int i=0;i<nStartPos.length;i++) zU]95I
{ U"/":w ~
nStartPos = input.readLong(); >8EIm
nEndPos = input.readLong(); yw2sK7
} \=i>}Sg
input.close(); @*!8
} 4R.rSsAH
catch(IOException e){e.printStackTrace ();} %gmf
catch(Exception e){e.printStackTrace ();} IojF/
} /JJU-A(
(oxe'\
A=Dzd/CUO
private void processErrorCode(int nErrorCode) HPT$)NeNc
{ A[^fG_l4
System.err.println("Error Code : " + nErrorCode); ?9.SwIxU&
} aO6w:IO
r;SA1n#
d'q,:="c
//停止文件下载 # sm>;+J
public void siteStop() |h4aJv
{ >}Fe9Y.o
bStop = true; 6f(K'v
for(int i=0;i<nStartPos.length;i++) xV}-[W5sr'
fileSplitterFetch.splitterStop(); 6o!+E@V b
?o?~Df&
"1yXOy^2
} \$W>@w0
} n}}$-xl
//负责部分文件的抓取 L^!E4[ ^4
**FileSplitterFetch.java a}EO7tcg,
*/ 1UT&kD!si
package NetFox; :OQx;>'
1ti+ Q0~
$0=f9+@5
import java.io.*; Z2!O)8
import java.net.*; }y;s(4
%9C_p]P*
ncjtv"2R
public class FileSplitterFetch extends Thread { z^'3f!:3
:*k
?@!dc6
String sURL; //File URL ]Vuq)#
long nStartPos; //File Snippet Start Position cA m>f[
long nEndPos; //File Snippet End Position rzsAnLxo
int nThreadID; //Thread's ID *#\da]"{
boolean bDownOver = false; //Downing is over rI23e[
boolean bStop = false; //Stop identical {d|e@`"T
FileAccessI fileAccessI = null; //File Access interface 2guWWFS
%L,mj
L/t'|<m
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException BUvE~l.,|
{ $t}t'uJ
this.sURL = sURL; __O@w.
this.nStartPos = nStart; 86y)+h`
this.nEndPos = nEnd; eEl}.W}
nThreadID = id; ?H3Ls~R
fileAccessI = new FileAccessI(sName,nStartPos);//定位 D;*P'%_Z
} +`'=K ;{U
2 ,RO
|L%}@e Vw_
public void run() `v) :|Q
{ ^}8qPBz
while(nStartPos < nEndPos && !bStop) ;n`SF~CU
{ \W:~;GMeD
LpN_s#
rY yB"|
try{ Vz[tgb]-
URL url = new URL(sURL); }04EM
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); G6@XRib3
httpConnection.setRequestProperty("User-Agent","NetFox"); )i|0Ubn[|
String sProperty = "bytes="+nStartPos+"-"; l/ufu[x!a
httpConnection.setRequestProperty("RANGE",sProperty); 0&wbGbg(W
Utility.log(sProperty); )"KKBil0
l=4lhFG,Mk
qJN!L))
InputStream input = httpConnection.getInputStream(); Ps<;DE\$f4
//logResponseHead(httpConnection); ^V,?n@c!
JiH^N!
v{tw;Z#
byte[] b = new byte[1024]; ~*NG~Kn"s
int nRead; 2nz^%pLT
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) IqD;*
{ ^6g^ Q*"
nStartPos += fileAccessI.write(b,0,nRead); .0 }eg$d
//if(nThreadID == 1) Q &~|P}
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ' m^nKG$"
} pg0Sq9qCN
*,az`U
Wl?0|{W
Utility.log("Thread " + nThreadID + " is over!"); T%q@jv{c
bDownOver = true; xNAX)v3Z
//nPos = fileAccessI.write (b,0,nRead); we?# Dui
} ,v\^efc:%
catch(Exception e){e.printStackTrace ();} |f67aN
} x#)CH}J
} GoSdo
f N_8HP6&
rD_\NgVAs
//打印回应的头信息 1/\JJ\
public void logResponseHead(HttpURLConnection con) C6` Tck!
{ UmEc")3
for(int i=1;;i++) b;xn0sDn#
{ s]X0}"cz
String header=con.getHeaderFieldKey(i); r{g8CIwGQ
if(header!=null) 6~b)Hc/
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ^GL>xlZ(
Utility.log(header+" : "+con.getHeaderField(header)); ?cur}`
else L*(Sh2=_
break; H;w8[ImK
} FHOF6}if
} XiW~? *Z
X\Gbs=sf6
Gv\39+9=
public void splitterStop() i0q<,VSl$_
{ lD9QS ;
bStop = true; 0Ba*"/U]t~
} oU`{6 ~;
2p|ed=ly%
(pv6V2i
} y?Cq{(
2r^G;,{
;X;q8J^_K_
/* {J~VB~('
**FileAccess.java yt+d f0l
*//文件访问(定位，写) [x[nTIg
package NetFox; ;)Fc@OXN>
import java.io.*; W @ ?*~
Fswr @du
_ci8!PP
public class FileAccessI implements Serializable{ C.`!?CW
*N65B#
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 r7FFZNs!
RandomAccessFile oSavedFile; JavSR1_
long nPos; IRG-H!FV
Wj INY
s:zz8oN
public FileAccessI() throws IOException 5}Z_A?gy
{ 6<SX%Bc~
this("",0); 2 Q}^<^r
} '5etZ!:
1fMl8[!JLu
XMlcY;W
public FileAccessI(String sName,long nPos) throws IOException It#T\fU
{ 3]rd!Gp=*
oSavedFile = new RandomAccessFile(sName,"rw"); S;tv4JY
this.nPos = nPos; lvp8{]I<
oSavedFile.seek(nPos); >Q#\X=a>
} zvOSQxGQ
IeT1Jwe
]@A31P4t|
public synchronized int write(byte[] b,int nStart,int nLen) }cO}H2m
{ ~0V,B1a
int n = -1; ,Pj UlcO_
try{ I?OnEw
oSavedFile.write(b,nStart,nLen); 2fFGS.l
n = nLen; (@i2a
} ItxC}qT
catch(IOException e) tlyDXB~+
{ dV7~C@k6k8
e.printStackTrace (); v5A8"&Jr
} 7N8a48$8
D` abVf
,V`[;~49
return n; G[lNgVbU@
} fI }v}L^
P$i d?
w,VUWja
} 1kczlTF
d>hLnz1O
krecUpo
/* DAVgP7h'
**SiteInfoBean.java ^3lEfI<pBm
*/ !Ct'H1J-
package NetFox; 94'0X
D:#e;K
i1^#TC$x
public class SiteInfoBean { T{4Ru6[
Sp\ 7
q~6((pWi|
private String sSiteURL; //Site's URL rvETt
private String sFilePath; //Saved File's Path I%tJLdL
private String sFileName; //Saved File's Name &Ef_p-e-P
private int nSplitter; //Count of Splited Downloading File )^]1j$N=3
Uu(FFd~3
[`U9
public SiteInfoBean() gaVQ3NqF
{//nSplitter的缺省值为5 w;]~2$
//default value of nSplitter is 5 ]:n! \G
this("","","",5); hWAZP=H
} "!z9UiA
IiB"F<&[j{
'w`3( ':=
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) M2rgB%W)m
{ o 4cqLMu
sSiteURL= sURL; dZ{yNh.]
sFilePath = sPath; bFwc>
sFileName = sName; {N`<THPP
this.nSplitter = nSpiltter; ~]C m
sHf.xc
yQdoy^d/4
} gF8n{b
-eQ70BXvB
[.LbX`K:
public String getSSiteURL() ,Vr'F
{ b5Vn_;V*
return sSiteURL; D&nVkZP>
} |^T?5=&Kt
m\;@~o'k
f,WAl\
public void setSSiteURL(String value) ~-zch=+u
{ *WK0dn
sSiteURL = value; 4@1C$|k
} @`H47@e
Hribk[99
>'e(|P4
public String getSFilePath() .F@0`*#rE~
{ :vRUb>z
return sFilePath; 0pl |
} 4pC.mRu 0
7FvtWE*
VmTPE5d
public void setSFilePath(String value) uwhb-.w
{ $G.ws
sFilePath = value; -$+`v<[r
} iw?*Wp25
3lT>C'qq
XXA1%Lw%
public String getSFileName() 59Lmv &s
{ 9Bw.Ih[Z
return sFileName; xji2#S%
} @WfX{485
1GI/gc\
k.("<)
public void setSFileName(String value) *9I/h~I
{ <{kr5<
sFileName = value; kZJ.G
} 8e*1L:oB!
h4lrt
m[%*O#_
public int getNSplitter() rA6lyzJ
{ A0`#n|(Ad!
return nSplitter; Fg<rz&MR
} UqEpeLK
:qL1jnR^
;8J+Q0V
public void setNSplitter(int nCount) - }2AXP2q
{ @ZTsl ?
nSplitter = nCount; `/\Z{j0_
} DU=rsePWE
} eh5j
568qdD`PS
2c4x=%
/* +8~C&K:
**Utility.java 4g}'/
*/ dyNKok#
package NetFox; ?O.1HEr
yo@S.7[/
[d}AlG!
public class Utility { %9lx)w
SFQYrY
6x8P}?
public Utility() ~L7@,d:
{ E3==gYCe*
~qj09
@.SuHd
} 1w/Ur'8we
D`C#O 7.N
//线程睡眠 hEv}g
public static void sleep(int nSecond) D<:J6W7]
{ ::eYd23
try{ : ZWKrnG
Thread.sleep(nSecond); cTQ]0<9:e
} \WN,.
catch(Exception e) y+g01z
{ W`2Xn?g
e.printStackTrace (); eK=<a<tx
} YN>k5\M_v
} MrGq{,6C
a/v!W@Zz}
//日志 X:1&Pdi
public static void log(String sMsg) }aC@ov]2
{ j68_3zpl
System.err.println(sMsg); ;"N4Yflz
} DbH"e
.vJlTg
K,'v{wSr
public static void log(int sMsg) OqcM3#
{ E)}& p\{E
System.err.println(sMsg); n^P~]1i
} /-v6jiM
} |{en){:
FC BsC#
5gZ6H/.
/* ]:X# w0UR
**TestMethod.java <*'%Xgm
*/ $wBF'|eU
package NetFox; znxP.=GB
@V>BG8Y
jFr[T
public class TestMethod { d%wy@h
bh&Wy<Y
<RaM@E
public TestMethod() ZJ Ke}F`l
{ ///xx/weblogic60b2_win.exe N">4I)
try{ eGF+@)K1"
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); psaPrE
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ;)'@kzi
SiteFileFetch fileFetch = new SiteFileFetch(bean); a6<UMJ
fileFetch.start(); &uMx*TTY
} d)yu`U
catch(Exception e){e.printStackTrace ();} iXsX@ S^F
6";ew:Ih^
"7X[@xX@
} {k"t`uo_
ah9P C7[
uihU)]+@t/
public static void main(String[] args) 7kDqgod^A
{ 1](PuQm7+
new TestMethod(); "AcC\iq
} ??u*qO:p
} Wp2$L-T&$
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