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)); g|$;jQ\_
} \M._x"
for(int i=0;i<nEndPos.length-1;i++) ez*QP|F*9
{ /T(9:1/G
nEndPos = nStartPos[i+1]; > l0H)W
} #qDm)zCM
nEndPos[nEndPos.length-1] = nFileLength; v0E6i!D/
} EEL3~H{(
} 66" 6>
S >CKm:7
SUUN_w~
//启动子线程 G\;6n
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; i-5,*0e6m
for(int i=0;i<nStartPos.length;i++) #eJ<fU6Da
{ ^V96lKt/
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), j4!O,.!T
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), {)!>e
nStartPos,nEndPos,i); +FqE fY4j
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ,#&7+e!]>P
fileSplitterFetch.start(); 5Lej_uqF
} T>L?\-
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), +)e|>
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); y;8&J{dd
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", bDtb6hL
nEndPos = " + nFileLength); ,%l}TSs
// fileSplitterFetch[nPos.length-1].start(); X~JP 1
\i%mokfbc
(4A'$O2
//等待子线程结束 NId.TaXh
//int count = 0; 5h6o}
//是否结束while循环 )rG4Nga5}
boolean breakWhile = false; PzNPwd
Tsa]SN14
]6)u$4X6$
while(!bStop) %%uE^nX>
{ 1d]F$>
write_nPos(); u YT$$'S
Utility.sleep(500); G7al@
breakWhile = true; ';/J-l/SE
0Q_*Z (
/YF:WKr2
for(int i=0;i<nStartPos.length;i++) 'D ?o^
{ Dpw*m.f
if(!fileSplitterFetch.bDownOver) cAEvv[
{ .\^0RyJE
breakWhile = false; U{hu7
break; 8SKrpwy
} er)I".|
} Xzf,S;XV~
if(breakWhile) 0zq'Nf?#3
break; S\&3t}_
<TRhnz
5j1d=h
//count++; NBc^(F"
//if(count>4) '"\M`G
// siteStop(); k<^M >` $
} &EQhk9j
CYW@Km{e
$%cc[[/U
System.err.println("文件下载结束！"); )XK\[tL
} $P0q!
catch(Exception e){e.printStackTrace ();} TI< x;p
} NEri{qxm
l_+@Xpl
x2#JD|0
//获得文件长度 3 J04 $cD
public long getFileSize() }:ZA)
{ mSxn7LG
int nFileLength = -1; ?s^3o{!<W
try{ YoKyiO!
URL url = new URL(siteInfoBean.getSSiteURL()); L#UR>Z#9
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !EB<N<P"t
httpConnection.setRequestProperty("User-Agent","NetFox"); ob{'Z]-V
'|^:,@8P9
!`Rh2g*o9
int responseCode=httpConnection.getResponseCode(); /;Tc]
if(responseCode>=400) ([u|j
{ s.}K?)mH
processErrorCode(responseCode); \7/yWd{N$
return -2; //-2 represent access is error E s5:S#
} 'Be'!9K*d
`)n4I:)2
Vi8A4
String sHeader; :/;/mHG]
L9D`hefz
d7X&3L%Oq
for(int i=1;;i++) FI$:R
{ 'RK"/ZhqE
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); MCT1ZZpPr
//Utility.log(in.readLine()); Fr8GGN~/
sHeader=httpConnection.getHeaderFieldKey(i); |HAJDhM,l
if(sHeader!=null) G:1'}RC :
{ XWp8[Cxs
if(sHeader.equals("Content-Length")) Iv6 q(c
{ /8h=6"
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); H0Pxw P>q
break; ~y!'\d>q<
} hJ'H@L7
} 6@J=n@J$p
else ((k"*f2%
break; c~Ka) dF|
} w6% Q"%rp
} m.e]tTe
catch(IOException e){e.printStackTrace ();} f V. c6
catch(Exception e){e.printStackTrace ();} !.]JiT'o
:jLL IqhB
q!5:M\
Utility.log(nFileLength); .gRj^pu
_8VP'S=
A IP~A]T
return nFileLength; az(<<2=
} PLyity-L[7
Cl}nPUoL
Nz,yd%ua
//保存下载信息（文件指针位置） 9B: 3Ha=
private void write_nPos() DZ8|20b
{ i<m(neX[H
try{ Pd*[i7zhC
output = new DataOutputStream(new FileOutputStream(tmpFile)); 86r5!@WN
output.writeInt(nStartPos.length); KQdIG9O+6
for(int i=0;i<nStartPos.length;i++) fGo4&( U
{ 9oWU]A\k>
// output.writeLong(nPos); xAQtX=FoX+
output.writeLong(fileSplitterFetch.nStartPos); |W">&Rb<t#
output.writeLong(fileSplitterFetch.nEndPos); @c3xUK
} &_ekA44E
output.close(); |^pev2g
} ]k0 jmE
catch(IOException e){e.printStackTrace ();} NK_|h%
catch(Exception e){e.printStackTrace ();} ,fVD`RR(W?
} p T(M>LP83
Lx^ eaP5
/U~|B.z@6
//读取保存的下载信息（文件指针位置） #<im?
private void read_nPos() 6[> lzEZ
{ X*8y"~X|vq
try{ %qP[+N&
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); )h!cOEt
int nCount = input.readInt(); A=Wg0eYy\
nStartPos = new long[nCount]; &],uD3:5O
nEndPos = new long[nCount]; =!O->C:
for(int i=0;i<nStartPos.length;i++) #o.e (C
{ q+ $6D;9
nStartPos = input.readLong(); Sqo+cZ
nEndPos = input.readLong(); Jg6Lr~!i
} `2s!%/
input.close(); +K57. n{
} WNjwv/
catch(IOException e){e.printStackTrace ();} kN1MPd4Yh
catch(Exception e){e.printStackTrace ();} kSQ8kU_w+
} ':'g!b`/
ly[LF1t
E$e7(D
private void processErrorCode(int nErrorCode) rH+OXGoB
{ 3FEJ 9ZyG
System.err.println("Error Code : " + nErrorCode); p*Bty@CRi
} RgE`Hr
DDg\oGLp
*sho/[~_
//停止文件下载 'Wonz<{'
public void siteStop() UkV?,P@l
{ a^|DD#5
bStop = true; Nk`UQ~g$
for(int i=0;i<nStartPos.length;i++) BT$p~XB
fileSplitterFetch.splitterStop(); n/H OP
\{,TpK.
W.7rHa
} m7 =$*1k
} GP|=4T}Bf
//负责部分文件的抓取 1gEH~Jmj
**FileSplitterFetch.java OW:*qY c;:
*/ jcH@*c=%e
package NetFox; nR!e(
^rkKE dd
[uq>b|`RG
import java.io.*; pMc6p0
import java.net.*; fCl}eXg6w
hGRj
XC4Z,,ah"
public class FileSplitterFetch extends Thread { QFyL2Xes/
mCtS_"W
8s%/5v"
String sURL; //File URL ^S9y7b^;r
long nStartPos; //File Snippet Start Position h`fVQN.3
long nEndPos; //File Snippet End Position 4JSPD#%f
int nThreadID; //Thread's ID +8=$-E=
boolean bDownOver = false; //Downing is over =lXj%V^8N
boolean bStop = false; //Stop identical ?0tg}0|
FileAccessI fileAccessI = null; //File Access interface da{]B5p\
$EMOz=)I#
s:`i~hjq
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 85{m+1O~
{ <_tmkLeZf
this.sURL = sURL; G4&s_M$
this.nStartPos = nStart; DA=U=F
this.nEndPos = nEnd; W+nu=iQ!
nThreadID = id; r );R/)&
fileAccessI = new FileAccessI(sName,nStartPos);//定位 /YKd [RQ
} d1/emwH
D)_ C@*q
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public void run() k_=SDm a
{ NzRvbj]
while(nStartPos < nEndPos && !bStop) rCyb3,W
{ OI R5QH
]n ?x tI
w-jElV
try{ OfsP5*d
URL url = new URL(sURL); 3JoY-
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); z(PUoV:?
httpConnection.setRequestProperty("User-Agent","NetFox"); ZTC>Ufu2!
String sProperty = "bytes="+nStartPos+"-"; Vs>Pv$kW
httpConnection.setRequestProperty("RANGE",sProperty); w7nt $L5
Utility.log(sProperty); #XV=,81w
Er~17$b
XGlt^<`
InputStream input = httpConnection.getInputStream(); W<Uu.Y{sG
//logResponseHead(httpConnection); ffCDO\i({
E'5*w6
BT_]=\zi
byte[] b = new byte[1024]; ]]xKc5CT
int nRead; Ku;fZN[g
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) h@)U,&
{ KuNLu31%
nStartPos += fileAccessI.write(b,0,nRead); WSThhI
//if(nThreadID == 1) wak26W>I3
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); x_PO;
} t@RYJmW
St=nf\P&F
;%|im?
Utility.log("Thread " + nThreadID + " is over!"); e r" w{
bDownOver = true; +qxPUfN
//nPos = fileAccessI.write (b,0,nRead); T.q2tC[bR
} b`0tfXzS5
catch(Exception e){e.printStackTrace ();} L aTcBcI
} ` ]|X_!J-
} UuG%5 ZC
! VwU=5
\j)Evjw
//打印回应的头信息 -K"'F`;W
public void logResponseHead(HttpURLConnection con) }v1wpv/b(
{ iT@`dEZ.
for(int i=1;;i++) >WLPE6E
{ r)(5,*v
String header=con.getHeaderFieldKey(i); ycGY5t@K@
if(header!=null) f^%3zWp|-
//responseHeaders.put(header,httpConnection.getHeaderField(header)); EZtU6kW"
Utility.log(header+" : "+con.getHeaderField(header)); Xj?Wvt
else # @\3{;{R
break; *miG<
} :XKYfc_y
} ~G@NWF?7
[%IOB/{N
Da^q9,|
public void splitterStop() /iW+<@Mas
{ ]kh]l8t^
bStop = true; Rq4;{a/j
} >Wg= Tuef
Y#U.9>h
i4C{3J^
} ?2<QoS
",r v%i2 f
"tCI_ Zi;
/* 6iFlz9XiI
**FileAccess.java }"Y<<e<z:
*//文件访问(定位，写) I#l}5e5
package NetFox; verI~M$v{
import java.io.*; &lc@]y8
HC0juT OiO
B`pBIUu
public class FileAccessI implements Serializable{ cJKnB!iL5
N,t9X7G&
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 ?7\V)$00(&
RandomAccessFile oSavedFile; UG1<Xfu|
long nPos; ,f03TBD}
OM'iJB6=
8jK=A2pTa
public FileAccessI() throws IOException glAS$<
{ ZlV
this("",0); e8,_"_1:F
} "tEp8m
1N5 E
wl=tN{R
public FileAccessI(String sName,long nPos) throws IOException opX07~1
{ UlXm4\@
oSavedFile = new RandomAccessFile(sName,"rw"); dT`nR"
this.nPos = nPos; ~Nh6po{
oSavedFile.seek(nPos); PW*Vfjf4
} " <bjS
8lQ/cGAc
hzD)yf
public synchronized int write(byte[] b,int nStart,int nLen) ~z^l~Vyg?
{ |N,^*xP(6
int n = -1; 4+olyBht
try{ pEB3qGA
oSavedFile.write(b,nStart,nLen); 8X;?fjl`"
n = nLen; \F _1C=
} g|)>65v
catch(IOException e) N2h5@*1Y
{ "|\hTRQ
e.printStackTrace (); +U fw
} UMcM&yu-
3s\UU2yr
]0i[=
return n; L03I:IJ
} %<i sdvF
b:1B >
5nPvEN/
} kHg|!
H4Bt.5O*
<Qq {&,Le
/* TtJX(N~
**SiteInfoBean.java He_O+[sc
*/ H UJqB0D ?
package NetFox; "jZZ>\
eDd&vf
#y\O+\4e
public class SiteInfoBean { &Vj@){
$.,PteYK
j;$f[@0o
private String sSiteURL; //Site's URL >iyNZ]."\
private String sFilePath; //Saved File's Path ``xm##K
private String sFileName; //Saved File's Name ?[Yn<|
private int nSplitter; //Count of Splited Downloading File |:)Bo<8
W83d$4\d
3qV^RW&
public SiteInfoBean() p{?duq=
{//nSplitter的缺省值为5 <?7CwW
//default value of nSplitter is 5 /X8a3Eqp9
this("","","",5); [_N1 .}e
} LM<*VhX
V7$ m.P#uM
Yjg$o:M
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 3P_.SF
{ 1@Ba7>%'
sSiteURL= sURL; Hc/7x).
sFilePath = sPath; e`Yj}i*bx]
sFileName = sName; 4Q+,_iP
this.nSplitter = nSpiltter; _0[z xOI
NK-}[!f
v9T3=
} hyxv+m[
\ZnA%hC
`=Mk6$%Cs
public String getSSiteURL() 5|0}bv O
{ n3e,vP? R
return sSiteURL; $#^3>u
} e{6wFN
_d!sSyk`
y9}qB:[bR
public void setSSiteURL(String value) >$kFYb>~q
{ mjOxmwo
sSiteURL = value; /}u:N:HA%
} j'*.=cwsp
03?ADjO
a,rXG
public String getSFilePath() \m`IgP*
{ ErN[maix#
return sFilePath; ' !huU
} hLfWDf*T|
2
_Q:ot'(~0-
public void setSFilePath(String value) P]"@3Z&w
{ ?;=7{Ej
sFilePath = value; 7L+Wj }m
} *wAX&+);
*Y1s4FXu2
do`'K3a"
public String getSFileName() }51QUFhL0
{ ^uo,LTq+
return sFileName; padV|hF3(e
} YBY;$&9
6cg,L:j#
9u~C?w
public void setSFileName(String value) L^u|=9
{ ?23J(;)s
sFileName = value; )^UqB0C6^
} dLQp"vs$
+:m)BLA4l
@3eMvbI
public int getNSplitter() \;%D;3Au
{ =ZHN]PP
return nSplitter; H!NGY]z*
} T7YJC,^m
:Gz$(!j1.'
h-.^*=]R6
public void setNSplitter(int nCount) uA`e
{ lBn<\Y!^
nSplitter = nCount; !B[Y?b:
} e_Zs4\^ef
} C&F% j.<
[YQtX_;w
oCwep^P(v
/* ;E}&{w/My
**Utility.java x~l"'qsK
*/ &=zJ MGa
package NetFox; 0"-H34M<D
D_\HX9
SdufI_'B
public class Utility { AsS~TLG9p
'bv(T2d~~
4o''C |ND
public Utility() qZQm*q(jM
{ :wzbD,/M
?@A@;`0Y
@#"K6
} ~+\A4BW
b5p;)#
//线程睡眠 }+ W5Snx
public static void sleep(int nSecond) =M{&g
{ m:EYOe,w
try{ ")boY/ P/w
Thread.sleep(nSecond); q89yW)XG
} E=v4|/['N
catch(Exception e) ABEEJQ
{ *~`oA~-Q
e.printStackTrace (); >iJxq6!
} Q#*qPgs
} 'o_ RC{k2"
U;4;>
//日志 (^=kV?<
public static void log(String sMsg) d6W&u~
{ VuBi_v6
System.err.println(sMsg); 1^Q!EV
} *nM.`7g*[
~9fTs4U
Z,3CMWHg
public static void log(int sMsg) G*v,-O
{ { F0"U=
System.err.println(sMsg); <^Q` y
} EU5(s*A
} $YBH;^#
ieyqp~+|4$
^J?2[(
/* KE)^S [Da
**TestMethod.java j{5oXW
*/ XF4NRs
package NetFox; RvW>kATb_F
I7ySm12}
Erl@]P4
public class TestMethod { GwD"j]
7 dG_E]&
F,5}3$
public TestMethod() yErvgf
{ ///xx/weblogic60b2_win.exe %D^j7`Z
try{ :)e/(I]
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Yh%
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); @iz6)2z
SiteFileFetch fileFetch = new SiteFileFetch(bean); {*|$@%y!
fileFetch.start(); &kOb#\11u
} avv/mEf-f
catch(Exception e){e.printStackTrace ();} /3vj`#jD
4p&SlJ
nYY'hjZ
} MU_ >+Wnf
b~G|Bhxa
RK]."m0c~#
public static void main(String[] args) '$OLU[(Y
{ RA62Z&W3
new TestMethod(); XG6UV('
} PDh1*bf{u
} wa9{Q}wSa
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