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)); zmF_-Q`c
} F|9 W7
for(int i=0;i<nEndPos.length-1;i++) [;%qxAB/_
{ *s}dtJ
nEndPos = nStartPos[i+1]; 5\lOZYHX
} mJp)nF8r~
nEndPos[nEndPos.length-1] = nFileLength; H1]G<N3
} &Nl:
} (bY#!16C:
7EO/T,{a
s%GhjWZS
//启动子线程 YLk/16r
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; $ba3dqbCW
for(int i=0;i<nStartPos.length;i++) 1jO}{U
{ 6"b =aPTi
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), @Pb!:HeJE
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), U:"E:Bxz;m
nStartPos,nEndPos,i); f 0D9Mp
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); _ 7X0
fileSplitterFetch.start(); k%Jv%m}aB
} r$<[`L+6
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 1 :<f[l
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 8SR~{
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", r&U5w^p
nEndPos = " + nFileLength); F6`$5%$M;?
// fileSplitterFetch[nPos.length-1].start(); ED[`Y.;
l@Uo4b^4x
gq\ulLyOeZ
//等待子线程结束 $n.oY5=\
//int count = 0; XDRw![H,~
//是否结束while循环 CvS}U%
boolean breakWhile = false; Z(k7&^d
;rC)*=4#
NBU[>P
while(!bStop) W6:ei.d+NS
{ 80DcM9^t8
write_nPos(); S2T~7-
Utility.sleep(500); !36jtKdM
breakWhile = true; 4Hc+F(
74i
}}y~\TB~}
for(int i=0;i<nStartPos.length;i++) vau0Jn%=ck
{ z)*7LI
if(!fileSplitterFetch.bDownOver) >VIb|YA
{ JI##l:,7r
breakWhile = false; 9x$Kb7'F
break; mWN9/+!
} 4EQ-48h17
} .sCi9d WR
if(breakWhile) SkU'JM7<95
break; G;Jqby8d
^UOVXRn
b+7!$
//count++; Y=94<e[f"
//if(count>4) no).70K
// siteStop(); M@%$9N)gd
} LVt{`
v 9\2/B
h' #C$i
System.err.println("文件下载结束！"); i^`]TOP
} ^FJ.C|l(
catch(Exception e){e.printStackTrace ();} y(!J8(yA
} /a@gE^TM
jG~zpZh
[ed6n@/O@
//获得文件长度 %+0 7>/
public long getFileSize() 98O0M#|d
{ vG;)(.:
int nFileLength = -1; {\u=m>2U|
try{ D}YAu,<K
URL url = new URL(siteInfoBean.getSSiteURL()); d'y\~M9(
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); KicPW}_
httpConnection.setRequestProperty("User-Agent","NetFox"); vK@t=d
L!2BE[~
+OM`c7M:
int responseCode=httpConnection.getResponseCode(); -SO`wL NV
if(responseCode>=400) ]m&cVy&
{ k?[|8H~2C
processErrorCode(responseCode); bUJ5jkZ)
return -2; //-2 represent access is error 5^:N]Mp"
} gN./u
_\mMgZu
"'i" @CR
String sHeader; }fzv9$]$
(4ueO~jb$
yhwwF n\
for(int i=1;;i++) >d1gVBhk
{ ~Q4 emgBD
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); [3&Y* W
//Utility.log(in.readLine()); {tqLH2cO
sHeader=httpConnection.getHeaderFieldKey(i); *}\}@0%
if(sHeader!=null) #*r u*
{ ;G 27S<Q
if(sHeader.equals("Content-Length")) 3JnBKh\n
{ Ro1b (+H
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); dG{D2~#
break; 9#C hn~ \
} LY>-kz]
} 8~q%H1[I\N
else ;}/@ar7s3
break; KNH.4A ,
} r0 mXRZC
} <]9%Pm#X
catch(IOException e){e.printStackTrace ();} =~7%R.U([e
catch(Exception e){e.printStackTrace ();} Jng,:$sZ
srX" vF
_hK83s4
Utility.log(nFileLength); U2~7qC,!Do
#a :W
Nhq&Sn2
return nFileLength; gA`x-`
} 7-*QF>w<a
IYb%f T
YbX3_N&
//保存下载信息（文件指针位置） ]6#7TT
private void write_nPos() +vR$%
{ l,(Mm,3
try{ `/+%mKlC|[
output = new DataOutputStream(new FileOutputStream(tmpFile)); 2`|1 !x
output.writeInt(nStartPos.length); ,sU#{.(
for(int i=0;i<nStartPos.length;i++) ">?ocJ\9
{ c(:qid
// output.writeLong(nPos); +1`Zu$|
output.writeLong(fileSplitterFetch.nStartPos); qJ\tc\
output.writeLong(fileSplitterFetch.nEndPos); g(9\r
} 4s{_(gy
output.close(); ^Md]e<WAp
} k{fTqKS%h
catch(IOException e){e.printStackTrace ();} mn5"kYy?
catch(Exception e){e.printStackTrace ();} M@LI(;
} !kzC1U
86.LkwlqoH
xUp[)B6?:
//读取保存的下载信息（文件指针位置） D'dE!CAUs
private void read_nPos() *TacVp
{ N;)Y+amg^
try{ y1zNF$<q
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); JjH#,@'.
int nCount = input.readInt(); {u/G!{N$
nStartPos = new long[nCount]; Z @:5vo
nEndPos = new long[nCount]; H*SEzVb
for(int i=0;i<nStartPos.length;i++) rkp 1tv
{ bC[TLsh7{2
nStartPos = input.readLong(); 'eKvt5&@
nEndPos = input.readLong(); vkQ81PEt
} /hC[>t<
input.close(); jQrj3b.NC3
} ^\Bm5QkS
catch(IOException e){e.printStackTrace ();} ]}K\&ho2
catch(Exception e){e.printStackTrace ();} 5P?7xRA
} ]klP.&I/0
.*9+%FN
@PYCl
private void processErrorCode(int nErrorCode) aFZu5-=x
{ v^Vr^!3
System.err.println("Error Code : " + nErrorCode); XET'XJWF%
} 2<Vw :+,
;B8#Nf
0zSRk]i.f
//停止文件下载 dr25;L? B
public void siteStop() 35 Y#eU2]
{ \t'v-x>2y5
bStop = true; zvvF9
for(int i=0;i<nStartPos.length;i++) tcovMn'
fileSplitterFetch.splitterStop(); Cfizh@<
jGM+
\,U#^Vr
} f?-=&||f78
} P>*g'OK^!G
//负责部分文件的抓取 lkj^<%N"r
**FileSplitterFetch.java Q}a, f75
*/ ;(]O*{F7k
package NetFox; RoL5uha,l
Bl)znJ^
Rnl 4
import java.io.*; zjyj,jP
import java.net.*; 8{mQmG4
h)O<bI8
6SYQRK
public class FileSplitterFetch extends Thread { Iyo ey
q\PHA
DXbzl +R
String sURL; //File URL R.(cGZS
long nStartPos; //File Snippet Start Position *b{C`[ =V
long nEndPos; //File Snippet End Position q>$[<TsE&}
int nThreadID; //Thread's ID bzz{ p1e
boolean bDownOver = false; //Downing is over ^8_`IT
boolean bStop = false; //Stop identical ) h*)_7
FileAccessI fileAccessI = null; //File Access interface uO4kCK<7C
auV'`PR
Kp_L\'.I5$
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException aJnZco6
{ =cy;{2S'p
this.sURL = sURL; (thDv rT@2
this.nStartPos = nStart; 'rT@r:6fn
this.nEndPos = nEnd; =Mg/m'QI
nThreadID = id; c1v,5c6d j
fileAccessI = new FileAccessI(sName,nStartPos);//定位 1|_8+)i;
} Dv7/eRt
s_(%1/{
uYh6q1@"~
public void run() ,bv?c@
{ 3 cd5g
while(nStartPos < nEndPos && !bStop) ##%R|P3
{ R]oi&"H@r)
"82<}D^;
wm3fd7T
try{ h6!o,qw"
URL url = new URL(sURL); ya+eGD@N':
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); p1dqDgF*
httpConnection.setRequestProperty("User-Agent","NetFox"); i(eLE"G+
String sProperty = "bytes="+nStartPos+"-"; 9Y9pKTU
httpConnection.setRequestProperty("RANGE",sProperty); #MZ0Sd8]&
Utility.log(sProperty); @$5!
:+1S+w
Ivw+U-Mz
InputStream input = httpConnection.getInputStream(); $gYy3y
//logResponseHead(httpConnection); qO5.NIs
1' #%UA
ELF,T(
byte[] b = new byte[1024]; !PCw-&
int nRead; =~Ac=j!q
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ?K<m.+4b*y
{ "@xF(fyg
nStartPos += fileAccessI.write(b,0,nRead); l:!4^>SC
//if(nThreadID == 1) .Yxx
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); (7P{k<5
} )~hsd+ 0t
!Ua74C
R~-r8dWcw
Utility.log("Thread " + nThreadID + " is over!"); "HWl7c3q
bDownOver = true; \wmNeGC2
//nPos = fileAccessI.write (b,0,nRead); Ga4Ru
} ~YxLDo'.t
catch(Exception e){e.printStackTrace ();} ]rEFWA
} T=8>0D^v5
} ulnG|3A9
RI#Cr+/
4|+6a6
//打印回应的头信息 D`r^2(WW
public void logResponseHead(HttpURLConnection con) a8?Zb^
{ /2,s-^
for(int i=1;;i++) sje}E+{[
{ E%g_O_
String header=con.getHeaderFieldKey(i); 'ADaz75`*r
if(header!=null) E'p5
//responseHeaders.put(header,httpConnection.getHeaderField(header)); %@<}z|.4
Utility.log(header+" : "+con.getHeaderField(header)); :#!m(s`
else Ga\E`J$c
break; /jI>=:z
} %eoO3"//
} 4m%RD&ZN
H79|%@F"
=1o_:VOG
public void splitterStop() )t G`a ;
{ &`7tX.iMlh
bStop = true; (h0i2>K
} s[:e '#^
-\;x>=#B
y8U|A0@$`
} *Z7W'-
&~ g||rq
l?_Iu_Qp
/* saOXbt(&
**FileAccess.java u1yc
*//文件访问(定位，写) @].Ko[P~
package NetFox; ]R^?Pa1Te4
import java.io.*; }U$Yiv
A_: Bz:
P,Fs7
public class FileAccessI implements Serializable{ #vhxW=L`=
imdfin?=
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 RdlcJxM
RandomAccessFile oSavedFile; EEQW$W1@
long nPos; /}?"O~5M"
R1'bB"$
]}/LNO*L"
public FileAccessI() throws IOException [wAI;=.
{ "}PaMR]
this("",0); D_,}lsrb
} -#v1b>ScY
=@b/Gl
>^%]F[Wo
public FileAccessI(String sName,long nPos) throws IOException %WrUu|xj>_
{ d$<HMs:o@
oSavedFile = new RandomAccessFile(sName,"rw"); #RoGyrLo
this.nPos = nPos; rlYAy5&
oSavedFile.seek(nPos); Q4Mp[
} C=}YKsi|R|
u"-q"0
*]%{ttR~
public synchronized int write(byte[] b,int nStart,int nLen) CuPZ0
{ 9;u$a^R.
int n = -1; )*N]Q
try{ oB8u[!
oSavedFile.write(b,nStart,nLen); iXtar;%
n = nLen; B8z3W9
} ,u|vpN
catch(IOException e) Y5fwmH,a-
{ Ch607i=
e.printStackTrace (); AW@I,
} W?8 |h
,Z*?"d
\R45#. P6X
return n; 6sb,*uSn%
} vj<HthC.k
xg)cA C\=
)sG`sET]`f
} F+Og8^!
+DS_'Tmr
epi{Ayb
/* I,D24W4l
**SiteInfoBean.java G"0YCi#I|
*/ `,~I*}T>5W
package NetFox; Kx?3]
qve2?,i8hM
g$eb@0$
public class SiteInfoBean { ZRO
7Zp'}Om<I
[*w^|b?
private String sSiteURL; //Site's URL V%?oI]" l
private String sFilePath; //Saved File's Path zDY!0QZLF\
private String sFileName; //Saved File's Name Sf[ZGY)
private int nSplitter; //Count of Splited Downloading File ,EW-21
HjKj.fV
zC6,m6Dv
public SiteInfoBean() AQ 3n=Lr
{//nSplitter的缺省值为5 zghUwW|K
//default value of nSplitter is 5 aoQK.7
this("","","",5); m\|I.BUG
} MGeHccqh2
a6"Pe07t
bb[.Kvq5
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) QbqEe/*$_
{ }X94M7+->
sSiteURL= sURL; 49&p~g
sFilePath = sPath; : 'M$:ZJ
sFileName = sName; \;&9h1?Mn
this.nSplitter = nSpiltter; A1x?_S"a
<*0^X%Vf\
Fy8KZWim
} !]4'f/
;>Y,b4B;
,%e.nj9
public String getSSiteURL() s QfP8}U
{ `s(T(l
return sSiteURL; ZWaHG_ U)
} .)|r!X
=Y>_b 2
['j_W$8n
public void setSSiteURL(String value) )]L:OE
{ IZBU<1M
sSiteURL = value; p't>'?UH|
} |,L_d2lb
!VU[=~
+CtsD9PA
public String getSFilePath() Zp]{e6J
{ +{N LziO
return sFilePath; =xScHy{$
} B ?96d'A
Alaq![7MDP
(D F{l?4x-
public void setSFilePath(String value) Fp..Sjh 6
{ q:@$$}FjL
sFilePath = value; Au,xIe!t
} msOk~ZPE6\
OoTMvZP[
vBAds
public String getSFileName() 7H~StdL/>
{ i]!CH2\
return sFileName; :$j6
} #`)zD"CO
W-zD1q~0?
_P.+[RS@
public void setSFileName(String value) p*E_Po
{ ) D:M_T2
sFileName = value; WgPpW!`
} K4NB#
#FKo:id`K
o^%4w>|
public int getNSplitter() Q.Uyl:^PxU
{ 0\#uxzdhJ
return nSplitter; DZKVZ_q
} l/0TNOA
9{_D"h}}
X>l
public void setNSplitter(int nCount) @1ZLr
{ ?kvkkycI
nSplitter = nCount; #R v&b@K
} lx,^Y647
} &*iar+vr
ujsJ;\c
'|Dm\cy
/* VXlTA>a }
**Utility.java bSsX)wHm
*/ ]@_M)[ x
package NetFox; A$vCm
I_N(e|s\U
fvccut;K
public class Utility { I@~hz%'
s,>1n0a
Z'p7I}-qr
public Utility() } <; y,4f
{ ,9Y{x
+ew2+2
6U)Lhf\'o
} 6n37R#(
~]8bTw@
//线程睡眠 nV'~uu
public static void sleep(int nSecond) e 5U<nf
{ VOH.EK?5
try{ l&cYN2T b
Thread.sleep(nSecond); M6U/. n
} os*QWSs
catch(Exception e) |9.`qv
{ 0p\R@{
e.printStackTrace (); fXCx!3m
} Zo
} _=@9XvNM
$$8xdv#
//日志 k @'85A`
public static void log(String sMsg) d4<Ic#
{ yEL^Y'x?
System.err.println(sMsg); R06q~>
} Qag@#!&n
E8#r<=(m
so_
public static void log(int sMsg) +o})Cs`|=A
{ g(m3 &
System.err.println(sMsg); %toxZ}OP
} v&oE!s#
} ?'uxYeX6
.n]P6t
NidG|Yg~Z
/* NFTEp0eP
**TestMethod.java :9!?${4R
*/ ]p>6r*/nw
package NetFox; 6'd=% V
R4=n">>Q
i_T8Bfd:
public class TestMethod { $>zLa_cn|
=BO} hk
p|VoIQY
public TestMethod() DPR=Xls
{ ///xx/weblogic60b2_win.exe oyV@BHJO@
try{ xgP/BK2"
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); NltEX14Af
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); U{n< n8
SiteFileFetch fileFetch = new SiteFileFetch(bean); KA1Z{7UK%
fileFetch.start(); &scHyt
} ~3 4Ly
catch(Exception e){e.printStackTrace ();} ]5b%r;_
%IGcn48J
4RYK9=NH
} Mo`7YS-Y
* Zb-YA
[|<2BQX
public static void main(String[] args) RGy4p)z*+
{ }|>mR];
new TestMethod(); l?E7'OEF:
} Vh1{8'GQ
} Dn;6O
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