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)); Z$Z`@&U=
} 2}D,df'W4
for(int i=0;i<nEndPos.length-1;i++) ].LJt['%8
{ CoKiQUW
nEndPos = nStartPos[i+1]; Us1@\|]
} !.9l4@z#
nEndPos[nEndPos.length-1] = nFileLength; kJ/+IGV^v
} 1oB$MQoc
} fW(;
*zJD$+Fo
#]"/{Z
//启动子线程 1Pu ,:Jt
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; !>\9t9
for(int i=0;i<nStartPos.length;i++) ;F|jG}M"
{ Q{O/xLf
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ;9K[~
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), IoQr+:_R
nStartPos,nEndPos,i); yU> T8oFh
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 'T%IvJ#Xu
fileSplitterFetch.start(); O2C6V>Q;
} ]OUD5T
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), $H4=QVj6
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 6KVV z/
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", ki#y&{v9Be
nEndPos = " + nFileLength); K/DH / r
// fileSplitterFetch[nPos.length-1].start(); XnD0eua#
5Qb;2!
%?@x]B9Y8E
//等待子线程结束 =1O?jrl~q
//int count = 0; AD(xaQ&T
//是否结束while循环 e,^pMg~
boolean breakWhile = false; }Bd_:#.mw
xOhRTxic
e!6eZ)l
while(!bStop) ubD#I{~J
{ %@>YNPD`E
write_nPos(); #sL/y
Utility.sleep(500); 0xv\D0
breakWhile = true; \Ph]*%
^<!Ia
#&k8TY
for(int i=0;i<nStartPos.length;i++) gEE9/\>%-
{ ,dOMW+{
if(!fileSplitterFetch.bDownOver) vXc!Zg~
{ /=bSt
breakWhile = false; cY{I:MA+h@
break; t`uc3ta"9
} wtq,`'B
} }lH;[+u3
if(breakWhile) c$/<l5Uw
break; {JTmP`&l
>)4.$#H
)4PB<[u
//count++; |%-YuD
//if(count>4) Rb?~ Rs\
// siteStop(); y!F:m=x<
} |l$ u<3
f]c<9Q>*
UBa-
System.err.println("文件下载结束！"); -E:(w<];
} n7@j}Q(&?
catch(Exception e){e.printStackTrace ();} 6I"C~&dt
} A^8x1ydZ
Mg+4huT
-gB{:UYi3
//获得文件长度 !1("(Eb
public long getFileSize() _$!`VA%
{ pVY4q0@
int nFileLength = -1; D]jkR} t
try{ gbJG`zC>U
URL url = new URL(siteInfoBean.getSSiteURL()); !h?=Wv ==]
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); YKNb59k
httpConnection.setRequestProperty("User-Agent","NetFox"); _;#9!"&
2av*o~|J*:
Zct!/u9 Q
int responseCode=httpConnection.getResponseCode(); z1#oWf{*
if(responseCode>=400) ,^HS`!s[ E
{ (N7O+3+G
processErrorCode(responseCode); ve6x/ PD
return -2; //-2 represent access is error SijS5irfk
} $ND90my
|g+!
} +1'{B"I
String sHeader; sx:Hv1d
uQWp+}>ZJy
4AuH1m)<
for(int i=1;;i++) Ohi D
{ +3)[>{~1Z
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); QsM*wT&aa
//Utility.log(in.readLine()); A=0@UqM
sHeader=httpConnection.getHeaderFieldKey(i); Qd?CTYNsv
if(sHeader!=null) *l:&f_ngV
{ 1c/ X
if(sHeader.equals("Content-Length")) K|Om5 p
{ tR5tPPw
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); oikxg!0S
break; Et.j1M|g
} ~oo'ky*H!
} q#jEv-j.
else /e .D/;]
break; %/Bvy*X&
} G@B*E%$9
} ^g[J*{+!W
catch(IOException e){e.printStackTrace ();} 22|"K**3J|
catch(Exception e){e.printStackTrace ();} r 3|4gG
'd+:D'
Psp^@
Utility.log(nFileLength); .N!{ U
6W$rY] h!
FZH-q!"^cK
return nFileLength; Ajg\aof0{
} ?3Pazc]+|
JA< :K0
jAZ >mo[
//保存下载信息（文件指针位置） H}B2A"
private void write_nPos() Jl_~_Z
{ `2,a(Sk#
try{ LZ4xfB(
output = new DataOutputStream(new FileOutputStream(tmpFile)); 8'\~%xw
output.writeInt(nStartPos.length); 5=Suj*s{D#
for(int i=0;i<nStartPos.length;i++) }s(C^0x
{ 8ZW?|-i
// output.writeLong(nPos); zWb-pF|
output.writeLong(fileSplitterFetch.nStartPos); Ww=O=c5uOu
output.writeLong(fileSplitterFetch.nEndPos); %EWq2'/5
} :pb67Al29
output.close(); Qww^P/vm
} 3T?f5+@I
catch(IOException e){e.printStackTrace ();} 'u1=XX h
catch(Exception e){e.printStackTrace ();} +v!v[qn
} Hsgy'X%om
KxX[S.C
!VFem~'d
//读取保存的下载信息（文件指针位置） aiJnfU]W
private void read_nPos() d+Ds9(gV
{ R3Ee%0QK
try{ Tt%}4{"
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Nq_A8Ph9
int nCount = input.readInt(); VVFV8T4
nStartPos = new long[nCount]; ZL=N[XW4'
nEndPos = new long[nCount]; -~\f2'Q
for(int i=0;i<nStartPos.length;i++) L{<7.?{Y
{ j %H`0
nStartPos = input.readLong(); gJk[Ja
nEndPos = input.readLong(); q1w|'V
} ,z[(k"
input.close(); nPOO3!<{
} 3}j1RYtz
catch(IOException e){e.printStackTrace ();} Za0gs @$
catch(Exception e){e.printStackTrace ();} VGB-h'
} VKNp,Lf
QLn+R(r
a*s\Em7f
private void processErrorCode(int nErrorCode) 5j`v`[B;
{ Yg&` U^7]B
System.err.println("Error Code : " + nErrorCode); rnH}#u+
} UGCox-W"
p1~*;;F
V_f`0\[x
//停止文件下载 2f^-~dz
public void siteStop() xDUaHE1co
{ LXNQb6!
bStop = true; }PZ=`w*O
for(int i=0;i<nStartPos.length;i++) 79wLT\&
fileSplitterFetch.splitterStop(); _ eiF@G
8%-%AWF]
Hd374U<8]T
} lLMPw}r<
} lJ&y&N<O
//负责部分文件的抓取 O|7yP30?M
**FileSplitterFetch.java R6<4"?*r
*/ !k-` eJ|
package NetFox; 5VKcV&D
A0>x9XSkJ
s1=+::
import java.io.*; . ,R4WA,
import java.net.*; m8HYWzN
A9;0y jae
(6clq:c7j
public class FileSplitterFetch extends Thread { ;'^, ,{
)2V@p~k?
r0{]5JZt/
String sURL; //File URL yl/a:Q
long nStartPos; //File Snippet Start Position 'hF@><sqk
long nEndPos; //File Snippet End Position |xeE3,8
int nThreadID; //Thread's ID fv2=B)8$
boolean bDownOver = false; //Downing is over 4.'JLArw
boolean bStop = false; //Stop identical GS4_jvD-
FileAccessI fileAccessI = null; //File Access interface C_Gzv'C"L
.8(%4ejJ(
;UpJ=?W
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException :Eo8v$W\RB
{ />F.Nsujy
this.sURL = sURL; 02pplDFsM
this.nStartPos = nStart; hfv%,,e
this.nEndPos = nEnd; VMF|iB
nThreadID = id; t%$@fjz
fileAccessI = new FileAccessI(sName,nStartPos);//定位 o\goE^,aeR
} 8(Fu
f'_M0x
\igaQ\~
public void run() oCuV9dA.
{ `pm>'
while(nStartPos < nEndPos && !bStop) ;RHNRVP
{ :1MMa6
hDvpOIUL1
GO~k '
try{ gl "_:atW
URL url = new URL(sURL); " '[hr$h3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); #KE;=$(S
httpConnection.setRequestProperty("User-Agent","NetFox"); @ae>b
String sProperty = "bytes="+nStartPos+"-"; "-0;#&!
httpConnection.setRequestProperty("RANGE",sProperty); &D*8l?A/1f
Utility.log(sProperty); 9^\hmpP@D
N"1QX6
Q.ukY@L.'
InputStream input = httpConnection.getInputStream(); '\t7jQ
//logResponseHead(httpConnection); O]ZC+]}/
q~O>a0f0
._,trb>o
byte[] b = new byte[1024]; 50Ad,mn<
int nRead; FWY[=S
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) JJ-i_5\q
{ 'hIU_
nStartPos += fileAccessI.write(b,0,nRead); tT-=hDw
//if(nThreadID == 1) hVf^
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); On%,l
} )E-E0Hl>7
8K^f:)Qw
aDveU)]=1
Utility.log("Thread " + nThreadID + " is over!"); +nQ!4
bDownOver = true; <T4(H[9B
//nPos = fileAccessI.write (b,0,nRead); a.,i.2
} G=cNzr9
catch(Exception e){e.printStackTrace ();} f[}|rf
} <\ETPL,<
} 1Z 6SI>p
!g2a|g
r0Z+RB^I
//打印回应的头信息 =YHt9fb$c
public void logResponseHead(HttpURLConnection con) j ug'g
{ j+Zt.KXjT
for(int i=1;;i++) %)JRbX<c
{ MD4\QNUa)*
String header=con.getHeaderFieldKey(i); 4E'|.tt(
if(header!=null) qHJ'1~?q
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ^#w{/C/n
Utility.log(header+" : "+con.getHeaderField(header)); Mj'lASI
else HamEIL-l.
break; 4#h?Wga
} +5-fk>o
} ZpWu,1
Bk@WW#b
{82rne`[
public void splitterStop() UE;Bb*<
{ w+Vk3c5uI)
bStop = true; :l`i4kx
} I.9o`Q[8&
h!Y?SO.b
/{R3@,D[]
} {XHk6w *-
|*E"G5WZM
~d>uXrb
/* ~bGnq, .$
**FileAccess.java G4m4k
*//文件访问(定位，写) &-4 ?!
package NetFox; ~},~c:fF?
import java.io.*; :d({dF_k;p
Q"'V9m7 i
m>YWxa
public class FileAccessI implements Serializable{ x< S\D&
17i$8
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 /x/4NeD
RandomAccessFile oSavedFile; N]u2ql&
long nPos; -ek1$y9)
m#MlH=-
agW9Go_F[
public FileAccessI() throws IOException B52H(sm
{ o\60n
this("",0); pUhc3L
} *:j-zrwu&
! ]\2A.b[
:A#+=O0\z
public FileAccessI(String sName,long nPos) throws IOException gY%&IHQ'
{ gLx/w\l6
oSavedFile = new RandomAccessFile(sName,"rw"); !EM#m@kZ{
this.nPos = nPos; `*d{PJTv
oSavedFile.seek(nPos); K%PxA#P}
} jE*Ff&]%m
]9@X?q
kXEtuO5FUM
public synchronized int write(byte[] b,int nStart,int nLen) Of#K:`1@
{ esteFLm`6
int n = -1; z^3Q.4Qc6^
try{ CpSK(2j
oSavedFile.write(b,nStart,nLen); )7w@E$l"
n = nLen; FT4l$g7"
} ~$*`cO
catch(IOException e) 6e/7'TYwT
{ 8sWr\&!
e.printStackTrace (); yl]UUBcQ
} #]X2^ND47
sbA2W~:
D2)i3vFB
return n; (Xj.iP
} >|(%2Zl
z{' 6f@]
'+6<U[ L
} -nGwuEngP
itHM7d
Ph Ttx(!
/* 6J"(xT
**SiteInfoBean.java qPUA!-'
*/ yXrd2?Rq@
package NetFox; f,JX"
on_H6Y@B52
3t*#!^$
public class SiteInfoBean { %i3{TL
j9>TTgy@
mZE8.`
private String sSiteURL; //Site's URL dEG ]riO
private String sFilePath; //Saved File's Path C rfRLsN]
private String sFileName; //Saved File's Name D!/0c]"
private int nSplitter; //Count of Splited Downloading File b@!:=_Mr
*7_@7=W,
ez+yP,.#
public SiteInfoBean() NFV_+{X\
{//nSplitter的缺省值为5 ?lyltAxs'
//default value of nSplitter is 5 8J):\jAZ6
this("","","",5); *V-ds8AQ
} `$M etQ
S QSA%B$<
]Ly8s#<g]N
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) D Kq-C%
{ ? osfL
sSiteURL= sURL; QheDF7'z
sFilePath = sPath; A'`P2Am
sFileName = sName; &8afl"_~
this.nSplitter = nSpiltter; s_v}=C^
@'Q%Jc(
RJLFj
} A-;^~I
Z>&K&ttJ
97(n\Wt2
public String getSSiteURL() W%WC(/hor
{ fSr`>UpxC
return sSiteURL; ^^eV4Y5`+
} jQkUNPHu
}I)z7l.
pKnIQa[c
public void setSSiteURL(String value) ,uO?;!t
{ LjCykk
sSiteURL = value; <0>[c<{V<
} UFL0K
c<>y!^g
p8_2y~!
public String getSFilePath() juXC?2c
{ 1P \up
return sFilePath; l%@dE7<&#Z
} 5/k)\`
E::<;9
4V1|jy3
public void setSFilePath(String value) &62`Wr0C
{ p#z;cjfSt
sFilePath = value; dhs#D:/{9
} K# /Ch5?
dw3'T4TC?
bYK]G+Ww
public String getSFileName() hg{ &Y(J!U
{ M{G$Pk8[
return sFileName; 6z PV'~q
} o;%n,S8J|^
unpfA#&!"
O4n8MM|`
public void setSFileName(String value) b~F!.^7Q
{ 1BTgGF
sFileName = value; "AV1..mu
} a~6ztEhGm
<e[!3,%L
3JTU^-S<
public int getNSplitter() u^!&{q
{ A xRl*B
return nSplitter; sBbL~ce50?
} %6"o8
2}597Hb
H RWZ0 '
public void setNSplitter(int nCount) 'aNahzb
{ ]S*E
nSplitter = nCount; "i}Z(_7yr
} t ]71
} NavOSlC+h
< rv1IJ
j\nE8WH
/* Pb*q;9
**Utility.java s8{-c^G:R
*/ N"&$b_u[
package NetFox; 8xc8L1;
Hxj'38Y
5f/@:~
public class Utility { x_]",2 W'
>aX:gN
vR<fdV
public Utility() M^Q&A R'F
{ ,HQ1C8
^u=PdBY
2LtU;}7s
} $,p.=j;P
>N :|Km\
//线程睡眠 *;>V2!N=U
public static void sleep(int nSecond) nomu$|I
{ InAU\! ew
try{ yp( ?1
Thread.sleep(nSecond); b/T20F{W\o
} i0i.sizu
catch(Exception e) 5?<|3
{ h4J{jh.
e.printStackTrace (); FZM ]o
} "cIGNTLFA
} ?3.(Vqwog
^A:!ni@3
//日志 [_B+DD=}
public static void log(String sMsg) 8L%%eM_O
{ 2nG{>,#C:O
System.err.println(sMsg); Sn_z
} wjN`EF5$}&
u>JqFw1
6RR4L^(m
public static void log(int sMsg) 1\M"`L/
{ =d:R/Z%,
System.err.println(sMsg); -='8_B/75
} g}\U, (
} ?6_"nT*}
Ah(\%35&
Ak<IHp^Q
/* dj8F6\
**TestMethod.java H>gWxJ 5
*/ O('i*o4!}
package NetFox; d=Rk\F'^J
vE^h}~5U
+&&MUT{ 3
public class TestMethod { ~YR <SV\{
f\U?:83
^bZ<9}
public TestMethod() k~'?"'
{ ///xx/weblogic60b2_win.exe l}U~I 3}).
try{ hX{g]KE>
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); bxPY'&
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 6qz!M
SiteFileFetch fileFetch = new SiteFileFetch(bean); ,f-T1v"
fileFetch.start(); zLJ:U`uh\
} I@y2HxM
catch(Exception e){e.printStackTrace ();} ~;!i)[-
="'rH.n #
$9j>VGf=
} ~Q.8 U3"
/j=DC9_
,}xpYq_/
public static void main(String[] args) f4 Sw,A
{ H|UV+Q0,
new TestMethod(); te!]9rR
} c0,gfY%sI$
} 7cOg(6N
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