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)); ;F!5%}OcL%
} iWB=sL&p
for(int i=0;i<nEndPos.length-1;i++) aS{n8P6vW
{ '}JhzKNj
nEndPos = nStartPos[i+1]; k_qd|
} qL&[K>2z
nEndPos[nEndPos.length-1] = nFileLength; EC6DW=
} DV+xg3\(>1
} ox>^>wR*
.TMs bZ|j
^aMg/.j
//启动子线程 5uNJx5g
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 4 \K7xM!
for(int i=0;i<nStartPos.length;i++) S)k*?dQ##R
{ I<4Pur>"
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), gsvuE
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), " 4K(jXq|
nStartPos,nEndPos,i); goRL1L,5
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); f/NH:1)y
fileSplitterFetch.start(); |`Ntv}
} |`f$tj
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), }~jlj
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 1N^[.=
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", z8~NZ;A
nEndPos = " + nFileLength); ICoHI
// fileSplitterFetch[nPos.length-1].start(); .hP D$o
|vwVghC
Zq|I,l0+E
//等待子线程结束 wd^':
//int count = 0; eV"h0_ox
//是否结束while循环 VT%NO'0
boolean breakWhile = false; /W30~y
:P\7iW
Ic:(Gi- %
while(!bStop) Ar|0b}=)>
{ el<s8:lA
write_nPos(); WZejp}x
Utility.sleep(500); e7r-R3_
breakWhile = true; 9ni1f{k
$s c
dA`IEQJL
for(int i=0;i<nStartPos.length;i++) #$+*;
{ } FlT%>Gw
if(!fileSplitterFetch.bDownOver) p8H'{f\G
{ -.@r#d/
breakWhile = false; @* jz o
break; b8VTo lJ
} "a>q`RaIQ"
} 5 +YH.4R
if(breakWhile) ]^n7
break; '!cCMTj
TnOggpQ6X
qIE9$7*X
//count++; C8:f_mJU
//if(count>4) r1m]HFN
// siteStop(); ]z;I_-
} qQ/^@3tXL
#7$ H
)VS=E7[
System.err.println("文件下载结束！"); /P3 <"?#k
} R)(T^V`{
catch(Exception e){e.printStackTrace ();} :WS@=sZN
} B=T'5&
=/+-<px
L>&t|T2
//获得文件长度 gHEu/8E
public long getFileSize() x0D*U?A
{ sPQQ"|wU
int nFileLength = -1; [{,T.;'<j
try{ Apag{Z]^B
URL url = new URL(siteInfoBean.getSSiteURL()); L>NL:68yN
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 9r<J"%*Q
httpConnection.setRequestProperty("User-Agent","NetFox"); "]x'PI 4J
5iw<>9X*
~i{(<.he
int responseCode=httpConnection.getResponseCode(); 9@:2wR |
if(responseCode>=400) Jk11fn;\>
{ JT7nG.9
processErrorCode(responseCode); G1tY)_-8[
return -2; //-2 represent access is error rjAn@!|:+
} r:'.nhe
t?&|8SId
I)6+6pm
String sHeader; k[YS8g-Q
z`}qkbvi
*3FKt&v 0
for(int i=1;;i++) 2'\H\|
{ dNH08q8P
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); g\:[ 55;8
//Utility.log(in.readLine()); 1~`fVg
sHeader=httpConnection.getHeaderFieldKey(i); `pS9_NYZ}
if(sHeader!=null) P[ck84F/
{ hJ? O],4J
if(sHeader.equals("Content-Length")) XS{Qnx_#
{ JPUW6e07o
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); FFpT~.
break; 4G0m\[Du
} (Q!}9K3
} .},'~NM]
else 7`Ak)F:V
break; h0f;F@I
} ~?Pw& K2
} 6OIte-c
catch(IOException e){e.printStackTrace ();} eA?RK.e
catch(Exception e){e.printStackTrace ();} I)[DTCJ~
aCj&O:]=
:#ik. D
Utility.log(nFileLength); ^|>PA:%
n\D&!y[]F
P=Jo+4O
return nFileLength; uym*a4J
} "| g>'wM*
xn(kKB.
At>DjKx]O
//保存下载信息（文件指针位置） vWv"
private void write_nPos() T2W eE@o
{ g2ixx+`?|:
try{ Y('#jU
output = new DataOutputStream(new FileOutputStream(tmpFile)); hH3RP{'=
output.writeInt(nStartPos.length); {9pZ)tB
for(int i=0;i<nStartPos.length;i++) L}b.ulkMD
{ !hy-L_wL]
// output.writeLong(nPos); zxl@(hd
output.writeLong(fileSplitterFetch.nStartPos); ]|ag
output.writeLong(fileSplitterFetch.nEndPos); ,PW'#U:
} i)#dWFDTv
output.close(); n'LrQU
} Uz8ff
catch(IOException e){e.printStackTrace ();} #A/
catch(Exception e){e.printStackTrace ();} Rsk4L0
} $GcqBg-Hi
]p GL`ge5
q`7PhA
//读取保存的下载信息（文件指针位置） :\c ^*K(9
private void read_nPos() ie95rZp
{ a#k6&3m&
try{ ()?(I?II
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); `UaD6Mc<Mz
int nCount = input.readInt(); +GN(Ug'R
nStartPos = new long[nCount]; `HSKQ52
nEndPos = new long[nCount]; _<V)-Y
for(int i=0;i<nStartPos.length;i++) F~W6Bp^W
{ ueWEc^_>
nStartPos = input.readLong(); 3(N$nsi
nEndPos = input.readLong(); .!3|&V'<
} P3=G1=47U
input.close(); RSRS wkC
} ksUcx4;a@F
catch(IOException e){e.printStackTrace ();} -d/ =5yxL
catch(Exception e){e.printStackTrace ();} JFmC\
} yx[/|nZDC4
7xlkZF
Mb}QD~=M
private void processErrorCode(int nErrorCode) 8kIksy
{ 1R%.p7@5QU
System.err.println("Error Code : " + nErrorCode); Pmx-8w
} )2o?#8J
h7oo7AP
JPHL#sKyz
//停止文件下载 +3BN}
public void siteStop() J*A,o~U|
{ |YWD8 +
bStop = true; adcE'fA<_
for(int i=0;i<nStartPos.length;i++) EME|k{W
fileSplitterFetch.splitterStop(); ;JT-kw6l5K
`$9x1dx
a58H9w"u)
} qInR1r<
} 9W5lSX#^;
//负责部分文件的抓取 *N<]Xy@
**FileSplitterFetch.java ,ZNq,$j
*/ ;igIZ$&
package NetFox; |wMN}bq|T
sll\g
]F~dlH1Wp
import java.io.*; ="H`V V_
import java.net.*; :3Ox~o
4pF*"B
!;A\.~-!G
public class FileSplitterFetch extends Thread { .p[ux vp
"&u@d~`-n
H*R"ntI?w
String sURL; //File URL Bsvr?|L\
long nStartPos; //File Snippet Start Position IEi^kJflU
long nEndPos; //File Snippet End Position uGGt\.$]s
int nThreadID; //Thread's ID C}Cs8eUn
boolean bDownOver = false; //Downing is over =UQ3HQD
boolean bStop = false; //Stop identical Btn?N
FileAccessI fileAccessI = null; //File Access interface 7n<{tM
!Ai@$tl[S
j,eo2HaL
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Zu[su>\
{ _V6ukd"B~
this.sURL = sURL; b8UO,fY q
this.nStartPos = nStart; wn%A4-%{
this.nEndPos = nEnd; p6V0`5@t
nThreadID = id; $6 f3F?y7
fileAccessI = new FileAccessI(sName,nStartPos);//定位 1GcE)e!>
} TD0 B%
/([kh~a
;)*eo_tQ
public void run() %tGO?JMkd
{ Bwxd&;E
while(nStartPos < nEndPos && !bStop) \R_C&=
{ Ti5-6%~&
r,p%U!S<hV
ZY+qA
try{ 6cXyJW
URL url = new URL(sURL); <]2wn
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); I\ob7X'Xu!
httpConnection.setRequestProperty("User-Agent","NetFox"); 4D4j7
String sProperty = "bytes="+nStartPos+"-"; Y:[u1~a
httpConnection.setRequestProperty("RANGE",sProperty); u*`GiZAO
Utility.log(sProperty); 8lrpve
#X1ND
<bWG!ZG
InputStream input = httpConnection.getInputStream(); TvbE2Q;/UL
//logResponseHead(httpConnection); /J;Kn]5e
GD$l||8
)y$(AJx$
byte[] b = new byte[1024]; #"~<HG}bR/
int nRead; y<Ot)fa$
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ~c `l@:
{ 57c8xk[.2
nStartPos += fileAccessI.write(b,0,nRead); q/,O\,
//if(nThreadID == 1) X \/#@T
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); NBGH_6DROw
} 5\nAeP
rx|pOz,:
4V`G,W4^J
Utility.log("Thread " + nThreadID + " is over!"); 5.GR1kl6
bDownOver = true; 'H;*W|:-]
//nPos = fileAccessI.write (b,0,nRead); evmeqQG=
} Avb\{)s+
catch(Exception e){e.printStackTrace ();} '`Hr}
} iXjM.G
} ?Ir:g=RP*
;4\;mmLVk
&6VnySE?
//打印回应的头信息 P&Vv/D
public void logResponseHead(HttpURLConnection con) j8sH|{H!Nq
{ 8":Q)9;%
for(int i=1;;i++) SmO~,2=
{ K}Qa~_
String header=con.getHeaderFieldKey(i); WpvhTX
if(header!=null) %pCTN P
//responseHeaders.put(header,httpConnection.getHeaderField(header)); es7=%!0
Utility.log(header+" : "+con.getHeaderField(header)); nxFBID
else eHUOU>&P]
break; K[YyBEid
} ~D>p0+-c
} !4+<<(B=E
'I;zJ`Trd
$XH^~i;
public void splitterStop() Q"#J6@
{ J{G?-+`
bStop = true; [:*)XeRK
} m1AJ{cs
jPkn[W# 6
*oix6
} HZZn'u
w0unS`\4
r3?o9D>
/* YS_;OFsd
**FileAccess.java |_U= z;Y
*//文件访问(定位，写) >9J:Uo1z
package NetFox; Tlr v={
import java.io.*; Xch~ 1K
.=; ;
47/iF97
public class FileAccessI implements Serializable{ N'=gep0V@
[Ch.cE_
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 7G],T++N
RandomAccessFile oSavedFile; klhtKp_p
long nPos; F:DrX_O%
_)-o1`*-
\fe]c :
public FileAccessI() throws IOException q5S9C%b
{ dAj$1Ke
this("",0); Znv,9-
} %&bY]w
gBD]}vo-
&)<)^.@3G^
public FileAccessI(String sName,long nPos) throws IOException sDV Q#}a
{ V(*(F7+
oSavedFile = new RandomAccessFile(sName,"rw"); cB&:z)i4
this.nPos = nPos; zbPqYhJzA
oSavedFile.seek(nPos); ddR>7d}N
} Z3!`J&
Ek}A]zC
9N3eN
public synchronized int write(byte[] b,int nStart,int nLen) d'sZxU
{ kcxAd
int n = -1; x,Vr=FB
try{ hpk7 Anp
oSavedFile.write(b,nStart,nLen); RG`1en
n = nLen; =g|FT
} =tY T8Q;al
catch(IOException e) |Q>IrT
{ teVM*-
e.printStackTrace (); Y <qm{e
} 9_s`{(0?
nQS|Lt_+
:Ux_qB
return n; ct}9i"H#1
} e(G|;a
GPkpXVm
{VoHh_[5%
} bN@ l?w
NaCy@
`9.r`&T6K
/* H>@+om
**SiteInfoBean.java igAtRX%Qx
*/ _J[P[(ab
package NetFox; xkR0
GuL<Z1<c
RpYERAgT
public class SiteInfoBean { cCc(fF*^
)\^-2[;
$,'*f?d
private String sSiteURL; //Site's URL \uMLY<]P
private String sFilePath; //Saved File's Path *uvQ\.
private String sFileName; //Saved File's Name )sp+8
private int nSplitter; //Count of Splited Downloading File FC"8#*x
7=, ;h
N17RLz *\
public SiteInfoBean() & ZB
{//nSplitter的缺省值为5 E1f\%!2l
//default value of nSplitter is 5 2GStN74Xr
this("","","",5); "C3/T&F
} O|UC ?]6
{FTqu.
nt.y !k
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) WOf 4o
{ 4v|W-h"K
sSiteURL= sURL; u>/ TE
sFilePath = sPath; \5cpFj5%
sFileName = sName; }4S6Xe
this.nSplitter = nSpiltter; ;6hOx(>`=
Dn}Jxu'(
2dgd~
} 4nz35BLr
C2)2)
YT8F#t8
public String getSSiteURL() c6/=Gq{.
{ sUm'
return sSiteURL; 7T'B6`-Ox
} r!{Up7uL
FU<Jp3<%
7vj2 `+r.
public void setSSiteURL(String value) dGTsc/$
{ :p6M=
sSiteURL = value; /vb`H>P
} -s'-eQF J
mlS$>O_aX
?b5^
public String getSFilePath() !$>R j
{ Nl(Foya%)
return sFilePath; VOh4#%Vj
} $,fX:x
W'u>#
`x%>8/
public void setSFilePath(String value) "Os_vlapHo
{ ps DetP
sFilePath = value; Xm2z}X(%
} &XUiKnNW
Yp2eBgo"
>~+ELVB&
public String getSFileName() L\z~uo3:
{ K)k<Rh[<
return sFileName; VTHH&$ZNq
} s=/v';5J2!
57'4ljvYi
U_c*6CK
public void setSFileName(String value) DkAAV9*
{ yyy|Pw4:Z
sFileName = value; I[X772K
} &~U ]~;@
`,*5wBC
1D!<'`)AY
public int getNSplitter() liz~7RY4
{ WvZ8/T'x
return nSplitter; 0NX,QD
} 4tmAzD
l0i^uMS
delu1r
public void setNSplitter(int nCount) D*|Bb?
{ 4x[S\,20
nSplitter = nCount; 07=mj%yV
} t}/( b/VD
} jdJ>9O0A,
R]*K:~DM
SGlNKA},A
/* qK&d]6H R
**Utility.java 3>VL}Ui}
*/ BsYa3d=}
package NetFox; YLn?.sV{[0
Z0r?|G0
i&GH/y
public class Utility { Xh;#
%sQ^.` 2
3=]sLn0L
public Utility() RhLVg~x
{ 3I-MdApT
q;)JISf.
0v$~90)
} K0Fh%Y4)QH
s.NGA.]$
//线程睡眠 WaR`Kp+>
public static void sleep(int nSecond) %FIE\9
{ _b;{_g
try{ y7Df_|Z
Thread.sleep(nSecond); fkNbS
} e'D&8z_;
catch(Exception e) I"7u2"@-8j
{ bhlG,NTP
e.printStackTrace (); b(O3@Q6[
} y:qUn!3
} 7o5BXF
WlBc.kFck
//日志 :I^;jdL
public static void log(String sMsg) _#8RSr8'y
{ _1!OlQ
System.err.println(sMsg); HLaRGN3,
} (7=!+'T"
I(7NQ8Hx
G.dTvLv
public static void log(int sMsg) ?[Q3q4
{ yx&51G$
System.err.println(sMsg); q0r>2c-d
} |kV*Jc k
} q6`b26
mahJSz(3
c?&X?<
/* s6.M\^
**TestMethod.java KRMQtgahc
*/ ;{tj2m,
package NetFox; x%!s:LVX
f-G:uI_
h2J/c#Qvh
public class TestMethod { 8~z~_TD6m@
6){]1h"
e-#BDN(O
public TestMethod() nWYN Np?h
{ ///xx/weblogic60b2_win.exe QD*35Y!d
try{ [dIXR
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); =Bhe'.]QSx
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); fd<:_f]v
SiteFileFetch fileFetch = new SiteFileFetch(bean); 'yG4 LF
fileFetch.start(); qjdMqoOCjl
} ={d>iByq
catch(Exception e){e.printStackTrace ();} [)zP6\I
v8[I8{41
xQXXC|T
} 8hJ%JEzga
RA'M8:$
$jI3VB
public static void main(String[] args) >$7v ;Q
{ f"SD/]q-
new TestMethod(); m\r@@!
} ![_*(8v}S
} \T:i{.i
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