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)); %Lh+W<;
} +|5O b
for(int i=0;i<nEndPos.length-1;i++) ZZCm438
{ '#,C5*`
nEndPos = nStartPos[i+1]; ;<GxonIV
} h9iQn<lp4.
nEndPos[nEndPos.length-1] = nFileLength; m@w469&<(q
} FS!)KxC/-
} CY[3%7fv
fH:S_7i
T,vh=UF%]
//启动子线程 j?k|-0
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; du#f_|xG
for(int i=0;i<nStartPos.length;i++) VhAJ1[k4!
{ aD_7^8>
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ucU7 @j
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), @v&s|X'
nStartPos,nEndPos,i); X-TGrdoX
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); w1VYU>
fileSplitterFetch.start(); Cx.##n0
} "Ehh9 m1&
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), >+Iph2]
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); \+l_H4\`K
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", bQwG"N
nEndPos = " + nFileLength); (~E-=+R[$&
// fileSplitterFetch[nPos.length-1].start(); Y5;afU='
P4eH:0=#
#Er"i
//等待子线程结束 x#zj0vI-8
//int count = 0; niW"o-}
//是否结束while循环 u^CL }t*
boolean breakWhile = false; o90g;Vog
UX<-jY#'V
k*\)z\f
while(!bStop) iXL^[/}&?M
{ d%epM5
write_nPos(); BGwD{6`U
Utility.sleep(500); hlze]d?z
breakWhile = true; hiA\~}sl n
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u U>L (
for(int i=0;i<nStartPos.length;i++) w%\{4T~
{ dGkw%3[
if(!fileSplitterFetch.bDownOver) $?]`2*i
{ [{[m)Z^
breakWhile = false; Rt&5s)O'
break; ?_A[E]/H
} v>Kh5H5e~
} @o^$/AE?
if(breakWhile) BnGoB`n
break; vD?D]8.F~Q
!J X7y%J
#)twk`!^
//count++; H-v[ShE
//if(count>4) :D-D+x
// siteStop(); ?CC.xE
} G e]NA]<
^,AE;ZT7
S<cz2FlV
System.err.println("文件下载结束！"); q9j~|GE|
} bu_@A^ys
catch(Exception e){e.printStackTrace ();} e!gNd>b {
} Haekr*1%
\/;c^!(<
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//获得文件长度 |)Dm.)/0)
public long getFileSize() /Wjc\n$'
{ KB :JVK^<
int nFileLength = -1; h-;> v.
try{ GIcq|Pe
URL url = new URL(siteInfoBean.getSSiteURL()); pV u[
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); I *sT*;U
httpConnection.setRequestProperty("User-Agent","NetFox"); Us'JMZ~
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Zy;jp*Q
int responseCode=httpConnection.getResponseCode(); N0kCdJv
if(responseCode>=400) FK~wr;[
{ 3'`&D/n
processErrorCode(responseCode); z _\L@b
return -2; //-2 represent access is error 9"+MZ$
} i7r)9^y
aY(s &
hp(MKfhH
String sHeader; Y,Z$U| U
5YNAb/!!F
GQY" +xa8]
for(int i=1;;i++) Oy=0Hsh@x
{ #<9'{i3
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); S|k@D2k=
//Utility.log(in.readLine()); mhhc}dS(H
sHeader=httpConnection.getHeaderFieldKey(i); { >[ ]iX
if(sHeader!=null) Ua 6O~,\
{ P[q>;Fx*
if(sHeader.equals("Content-Length")) H+Bon=$cE!
{ Ji9o0YR
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); @#t<!-8d
break; sfw*_}y
} IO"P /Q
} OhCdBO
else Ew PJ|Z^
break; @Q2E1Uu%
} oYf+I
} f['lY1#V1
catch(IOException e){e.printStackTrace ();} ?#:']q
catch(Exception e){e.printStackTrace ();} Ezew@*(
rCA!b"C2
Tb?XKO,
Utility.log(nFileLength); 8gEp5
27c0wzq
O4oN)
return nFileLength; ">1wPq&
} %gFIu.c
tg#jjXV\0p
:KX*j$5U
//保存下载信息（文件指针位置） Ji!i}UjD7!
private void write_nPos() (EWGX |QA
{ 86-Rm
try{ NwYQ6VEA
output = new DataOutputStream(new FileOutputStream(tmpFile)); w2'z~\dG8
output.writeInt(nStartPos.length); W[)HFh(#
for(int i=0;i<nStartPos.length;i++) ,#,K_oz
{ M=;csazN
// output.writeLong(nPos); F3!@|/<w
output.writeLong(fileSplitterFetch.nStartPos); t6KKfb
output.writeLong(fileSplitterFetch.nEndPos); (9aOET>GG
} ]6`K
output.close(); MDIPoS3BRa
} CStNCBZ|\
catch(IOException e){e.printStackTrace ();} YiuV\al
catch(Exception e){e.printStackTrace ();} |-\anby<
} Y)]VlV!`
Hn)? xw]x
8h|}Q_
//读取保存的下载信息（文件指针位置） `{Oqb
private void read_nPos() wj}LVyV
{ ^C^I
try{ ]JGq{I>%+6
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ;7qzQ{Km
int nCount = input.readInt(); l 7dm@S
nStartPos = new long[nCount]; B:v_5e\f@
nEndPos = new long[nCount]; ~YW;'
for(int i=0;i<nStartPos.length;i++) u?SwGXi~8
{ ceks~[rP
nStartPos = input.readLong(); xu-bn
nEndPos = input.readLong(); dgX%NKv1
} m2(}$z3e
input.close(); P6>C+T1
} -b?M5P*:
catch(IOException e){e.printStackTrace ();} @YaI5>,/
catch(Exception e){e.printStackTrace ();} x@oxIXN
} Jg'#IM
OMjPC_
KV;q}EyG
private void processErrorCode(int nErrorCode) ip'{@1L
{ Y}.f&rLe
System.err.println("Error Code : " + nErrorCode); >+i+_^]
} Lhg
F)eP55C6
J7{D6@yLS
//停止文件下载 CL5^>.}
public void siteStop() `:r-&QdU o
{ GGHeC/4
bStop = true; o(54 A['
for(int i=0;i<nStartPos.length;i++) .HY,'oC.
fileSplitterFetch.splitterStop(); %|JL=E}%|
J#@+1 Nt
u"hr4+/
} a|t{1]^w`
} OC,yLQ
//负责部分文件的抓取 xgNV0;g,
**FileSplitterFetch.java sEw ?349Bz
*/ uInI{>
package NetFox; h'G
PK&&Vu2M
CcV@YST?
import java.io.*; qycf;Kl:6
import java.net.*; +Gy9K
?@MY+r_G
P$h) Y
public class FileSplitterFetch extends Thread { HtE^7i*_
8?<J,zu@AV
JCZ&TK
String sURL; //File URL @*6_Rp"@
long nStartPos; //File Snippet Start Position }>,%El/
long nEndPos; //File Snippet End Position gV:0&g\v
int nThreadID; //Thread's ID (C`nBiL<
boolean bDownOver = false; //Downing is over 3ErV" R4"$
boolean bStop = false; //Stop identical d=vD Pf
FileAccessI fileAccessI = null; //File Access interface Z5wQhhH
?0z/i^I
zh?B-"O=5
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 2.{<C.BK{
{ $j(4FyH\
this.sURL = sURL; l_2l/ff9
this.nStartPos = nStart; i8EKzW
this.nEndPos = nEnd; p ~+sk1[.
nThreadID = id; ojj T
fileAccessI = new FileAccessI(sName,nStartPos);//定位 $'#}f?
} R*ex!u60M
ecvZwL
-biw{
public void run() d|UH AX
{ *z~J ]
while(nStartPos < nEndPos && !bStop) oOXJ7|n
{ oc-o>H
%>O}bdSf
5*B'e{C
try{ NLgeBLB
URL url = new URL(sURL); @k:@mzB7R
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); K_N`My
httpConnection.setRequestProperty("User-Agent","NetFox"); $x+ P)5)
String sProperty = "bytes="+nStartPos+"-"; 9(KffnE^
httpConnection.setRequestProperty("RANGE",sProperty); F*:H&,
Utility.log(sProperty); 4dSAGLpp
e6T?2`5P
98{n6$\
InputStream input = httpConnection.getInputStream(); h{)`W ]~
//logResponseHead(httpConnection); 6p,}?6^
k5)IBO
OXoEA a
byte[] b = new byte[1024]; `soQp2h-
int nRead; *9r 32]i;
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Z3Xgi~c
{ `E>o:tff
nStartPos += fileAccessI.write(b,0,nRead); xkaed
//if(nThreadID == 1) % <%r
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); "MOmJYH
} <(~geN
=D 5!Xq'|
MB.LHIo
Utility.log("Thread " + nThreadID + " is over!"); Zl2doXC
bDownOver = true; x1#6~283
//nPos = fileAccessI.write (b,0,nRead); &v r0{]V^
} X=JAyxY
catch(Exception e){e.printStackTrace ();} ^DR`!.ttr
} LkXF~
} O<0-`=W,a
).HnK
M""X_~&I"
//打印回应的头信息 w6k^|."
public void logResponseHead(HttpURLConnection con) ]G=^7O]`C!
{ Jz_`dLL^w
for(int i=1;;i++) !=+hU/e
{ G9> 0w)r
String header=con.getHeaderFieldKey(i); 9kU|?JE
if(header!=null) :UsNiR=l
//responseHeaders.put(header,httpConnection.getHeaderField(header)); \,b_8^
Utility.log(header+" : "+con.getHeaderField(header)); *wz62p
else /vFdhh
break; 9t0NO-a
} &eX^ll
} cU=EXyP%
/57)y_ \
Y<`uq'V
public void splitterStop() 7ZpU -':
{ Hh<}~s
bStop = true; pS)/yMlVj
} ;KW}F|
sMqAuhw$.
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} ;z^C\=om
Tk0Senq,
1x4{~g\
/* t{ScK%S6
**FileAccess.java W-@}q}A
*//文件访问(定位，写) Z&0*\.6S~
package NetFox; /*{s1Zcb
import java.io.*; Ea[K$NC)#
OX)[?1m8
c4n]#((%a
public class FileAccessI implements Serializable{ N[AX]gOJ
Q+'QJ7fw'|
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 L+y90 T6?
RandomAccessFile oSavedFile; &7t3D?K'qX
long nPos; 72>/@
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G4eY}3F7,4
public FileAccessI() throws IOException pElAY3
{ 3]1uDgfr
this("",0); 7nAB^~)6l
} n[pW^&7x
StJ&YYdD
p$ %D
public FileAccessI(String sName,long nPos) throws IOException fPW(hb;
{ fB3W} dr
oSavedFile = new RandomAccessFile(sName,"rw"); 1zUo.Tg0
this.nPos = nPos; D|p`~(
oSavedFile.seek(nPos); PYp<eo\
} [vs5e3B)
'XHKhpm<
ki[Yu+';}
public synchronized int write(byte[] b,int nStart,int nLen) WS?"OTH.^\
{ h{&}p-X&[
int n = -1; 3-5X^!C
try{ Eh&et0&=g
oSavedFile.write(b,nStart,nLen); ?|t9@r
n = nLen; q'%-8t
} G'sEbw'[
catch(IOException e) gE>_:s
{ #PpmR_IX
e.printStackTrace (); Z;6v`;[
} ?UlAwxn
MwN.Ll
*uq;O*s
return n; 451TTqc
} 1 U|IN=
kCO`JAH#
u"*@k^}(
} }&Gt&Hm>K
n9}3>~ll
*TEgV
/* _{fh/{b1
**SiteInfoBean.java U=4tJb
*/ 8%qHy1
package NetFox; ]\y:AkxhJ
^x8yWbrE
9 -\.|5;:
public class SiteInfoBean { lC8DhRd0_
38Q>x
mlsM;Ad2
private String sSiteURL; //Site's URL Gy+/P6
private String sFilePath; //Saved File's Path Lb2bzZbhx
private String sFileName; //Saved File's Name #Ont1>T,G
private int nSplitter; //Count of Splited Downloading File WQ(*A $
<g SZt\
|#p`mc%f~\
public SiteInfoBean() 8cV3VapF
{//nSplitter的缺省值为5 o& g01t
//default value of nSplitter is 5 sOegR5?;
this("","","",5); G1t{a:
} 95 7Cr
+9MoKn=h
FwB}@)3
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) z@Klj qN
{ tnv @`xBn
sSiteURL= sURL; JVPl\I
sFilePath = sPath; ?pS,?>J f
sFileName = sName; ZK1H%&P=R
this.nSplitter = nSpiltter; _O76Aw-@l
;<j[0~qp:
+K6j p
} 'jr\F2
v{/z`J!JR
`1AVw]k
public String getSSiteURL() ;7jszs.6%
{ #GTR}|Aga
return sSiteURL; :qfP>Ok
} FaNr}$Pe
-@6R`m=>
T*AXS|=ju
public void setSSiteURL(String value) &:K!$W
{ #le1 ^ <w7
sSiteURL = value; E}7@?o7u}
} I?2S{]!?
U3R;'80 f
/$w,8pV=
public String getSFilePath() g4Y1*`}2f
{ P2U^%_~
return sFilePath; WOw( -
} (gdi2
zEHX:-f8
(KHO'QNMt^
public void setSFilePath(String value) +v!%z(
{ reBAxmt
sFilePath = value; UDBMf2F]
} }:04bIaV
16J"QUuG
E79'<;K,zs
public String getSFileName() (qG}`?219J
{ $,@PY5r
return sFileName; })?t:zX#*
} `#/0q*$
?@*hU2MTC
0bl?dOV{
public void setSFileName(String value) %<^IAMkp
{ uWtj?Q+M|
sFileName = value; 4l2/eh]Hc(
} hDn?R}^l{
5_H`6-q
zwLJ|>
public int getNSplitter() >8v4fk IK
{ {*BZ;Xh\8
return nSplitter; Em<B9S
} Whd\Ub8(
JZl"k
#YiphR&
public void setNSplitter(int nCount) j[ fE^&
{ w \U?64
nSplitter = nCount; *F^t)K2
} ^\(<s
} HQy:,_f@
prk@uYCa =
!l(O$T9T
/* qh]D=i
**Utility.java 6zZT5 Kn
*/ 6T9?C|q
package NetFox; I2&R+~ktR
(:9=M5d
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public class Utility { B-1Kfc
CVAX?c{
A)5;ae
public Utility() w$evAPuz^
{ u6t%*''
S^q%+Z
Ux!q(9<_
} YXlaE=9bn
d5YL=o
//线程睡眠 JeXA*U#
public static void sleep(int nSecond) l:.q1UV
{ kM;}$*?
try{ riu_^!"Z_
Thread.sleep(nSecond); oG$OZTc
} cHAq[Ebp2!
catch(Exception e) o'KBe%@/
{ MwHxn%
e.printStackTrace (); J5zKwt
} oB8LJZ;
} Q>yO,H|
}v`Z.?|Z
//日志 sLOkLz"x
public static void log(String sMsg) Maw$^Tz,
{ <ht^Ck
System.err.println(sMsg); qCI0[U@
} [!S%nYs&8L
fAT+x1J\
5M? I-m
public static void log(int sMsg) [NU@A>H
{ <Em|0hth
System.err.println(sMsg); S^:7V[=EgI
} (,j~s{
} \^3cNw
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7.nNz&UG]5
/* 5`FPv4
**TestMethod.java R/\qDY,@
*/ qM(@wFg
package NetFox; 8FJPw"9
wl0i3)e:
ZRP[N)Ld$
public class TestMethod { n%d7`?tm4
`G<|5pe
4CK$W`V
public TestMethod() &9khIJIn
{ ///xx/weblogic60b2_win.exe 'R nvQ""
try{ +wE>h>?;
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Z!z#+G
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); IQyw>_~]
SiteFileFetch fileFetch = new SiteFileFetch(bean); |5(un/-C
fileFetch.start(); 4<S=KFT_
} p&lT! 5P!A
catch(Exception e){e.printStackTrace ();} Tilw.z
3z!^UA>q
>8EmfjUoc
} '=(@3ggA:
[W8?ww%qT
_YA;Nd#%k
public static void main(String[] args) Eikt,
{ #OsUF,NU
new TestMethod(); hOr4C4
} iz:O]kI
} 4=ZN4=(_[
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