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)); :=9]c17=
} 1RKW2RCaW_
for(int i=0;i<nEndPos.length-1;i++) !J=sk4T
{ Pub0IIs
nEndPos = nStartPos[i+1]; g!i45-n3gt
} qClHP)<
nEndPos[nEndPos.length-1] = nFileLength; r|*&GHo L
} fGv#s X
} @Eb2k!T
N-g8}03
BI:k#jO!
//启动子线程 5*\\J&H
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; {ls+dx/
for(int i=0;i<nStartPos.length;i++) SSBg?H'T
{ zd]D(qeX
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), kF;5L)o
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), \*\R1_+
nStartPos,nEndPos,i); ^VT1vu %03
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Uu7dSU
fileSplitterFetch.start(); ez3Z3t`
} s!+"yK
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), HP.E3yYK
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); a{[+<8=@1
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", :y2p@#l#
nEndPos = " + nFileLength); ~dHM4lGY
// fileSplitterFetch[nPos.length-1].start(); 93IFcmO.H@
]0B|V2D#e
Gq#~vr
//等待子线程结束 B$?qQ|0:=
//int count = 0; NDO\B,7
//是否结束while循环 i{^Z1;Yl
boolean breakWhile = false; -xg2q V\c
pbHsR^
rg_Q"g
while(!bStop) +KEkmXZ
{ 3E^M?N2oc
write_nPos(); 1\L[i];L8
Utility.sleep(500); ?@6/Alk
breakWhile = true; @OV-KT[>
2eQdQwX
JM.XH7k
for(int i=0;i<nStartPos.length;i++) _U|7'^|
{ _kFYBd
if(!fileSplitterFetch.bDownOver) ;oH,~|K
{ kJs^ z
breakWhile = false; N"[B=fU}
break; (/" &
} "()sb?&
} !.5),2
if(breakWhile) 1U\$iy8}
break; /"qcl7F
7yI@"c#O
FZpKFsPx
//count++; (y4#.vZh:
//if(count>4) M] V.!z9B
// siteStop(); FdOFE.l
} ts9pM~_~
PHM:W%g:
7q9gngT1LA
System.err.println("文件下载结束！"); $<)Yyi>6E
} a?cn9i)#
catch(Exception e){e.printStackTrace ();} ?Ce#BwQ>
} H ;@!?I
-[#n+`M
N1--~e
//获得文件长度 0_<Nc/(P
public long getFileSize() 6DSH`-;
{ h=RDO
int nFileLength = -1; @y~P&HUN
try{ J>S3sP
URL url = new URL(siteInfoBean.getSSiteURL()); Il~01|3+m
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); [!*xO?yCJ
httpConnection.setRequestProperty("User-Agent","NetFox"); 0^!Gib
<ZPZk'53<f
1-;?0en&0
int responseCode=httpConnection.getResponseCode(); l`n5~Fs
if(responseCode>=400) - HOnB=
{ CUmH,`hu
processErrorCode(responseCode); \MYU<6{u
return -2; //-2 represent access is error ij)Cm]4(2
} {/M\Q@j
^o<[. )
X}JWf<=q
String sHeader; D,W\ gP/h%
L=1~ f-
] VG?+
for(int i=1;;i++) !QC<n/
{ H*U`
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 2*[Un(
//Utility.log(in.readLine()); |+EKF.K
sHeader=httpConnection.getHeaderFieldKey(i); 6&!l'[hU
if(sHeader!=null) $AwZ2HY
{ LDX*<(
if(sHeader.equals("Content-Length")) LcUlc)YH5
{ W%8+t)
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ?n*fy
break; ]tVl{" .{
} )A83A<~
} d(l|hmj4j9
else nP_=GI
break; XJFnih
} q+/l"&j.
} F.KrZ3%4iB
catch(IOException e){e.printStackTrace ();} k:0P+d
catch(Exception e){e.printStackTrace ();} Ow3a0cF[9
46ChMTt
o>u!CL<
Utility.log(nFileLength); {})y^L
hDtKnF
YC)hX'A\
return nFileLength; uX0 Bp8P
} TzY!D*%z
Q&wYc{TUbm
"t+r+ipf])
//保存下载信息（文件指针位置） :0dfB&7
private void write_nPos() 2?1}ZXr
{ hT=f;6$
try{ ]PVto\B=
output = new DataOutputStream(new FileOutputStream(tmpFile)); I=b'j5c
output.writeInt(nStartPos.length); .\4l'THn,0
for(int i=0;i<nStartPos.length;i++) yM17H\=
{ lVT&+r~r
// output.writeLong(nPos); SY8U"Qc;9
output.writeLong(fileSplitterFetch.nStartPos); k!c7a\">{
output.writeLong(fileSplitterFetch.nEndPos); GiqBzV3"
} {9{J^@@
output.close(); 7<4xtK`+b
} yjv&4pIc1
catch(IOException e){e.printStackTrace ();} H oS|f0
catch(Exception e){e.printStackTrace ();} i0i`k^bA
} eEie?#Z/6
cP('@K=p
b\M b*o
//读取保存的下载信息（文件指针位置） F#^L9
private void read_nPos() kpWzMd &RK
{ :'ihE\j
try{ hqWbp*
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); jRwa0Px(
int nCount = input.readInt(); e9}8RHy1$
nStartPos = new long[nCount]; "$Y(NFb
nEndPos = new long[nCount]; ] EV`dIk
for(int i=0;i<nStartPos.length;i++) @oA0{&G{
{ L3g9b53\
nStartPos = input.readLong(); [{/$9k-aF?
nEndPos = input.readLong(); Ba<#1p7_
} 2gH_$
input.close(); <YSg~T
} Djyp3uUA/
catch(IOException e){e.printStackTrace ();} \E~Q1eAJT
catch(Exception e){e.printStackTrace ();} pbFYiu+
} [}@n*D$
$oc9 |Q 7
@,GjeF]!
private void processErrorCode(int nErrorCode) O68bzi]
{ VZIKjrKs
System.err.println("Error Code : " + nErrorCode); =}"R5
} h2AGEg'g2[
S>(z\`1qm
a&8l[xe1
//停止文件下载 ^b:Xo"q#H
public void siteStop() QW,cn7
{ kO jEY
bStop = true; #*+;B93)
for(int i=0;i<nStartPos.length;i++) ]|t9B/()i
fileSplitterFetch.splitterStop(); 0}6QO
>2nF"?"=
a4:`2
} f8R+7Ykx
} CJ0$;et
//负责部分文件的抓取 FF8WTuzB+
**FileSplitterFetch.java }Z^FEd"y
*/ QXsfp
package NetFox; j`{fB}
%bEGv:88s
gYRqqV
import java.io.*; >y&[BB7S6
import java.net.*; b_q!>&c
pb~Ps#"Zg
+}&pVe\t
public class FileSplitterFetch extends Thread { bb*c+XN0
RA!x
#W_i{bdO
String sURL; //File URL 3O#~dFnp
long nStartPos; //File Snippet Start Position rve7YS'
long nEndPos; //File Snippet End Position 5T7_[{
int nThreadID; //Thread's ID "tqS|ok.
boolean bDownOver = false; //Downing is over Ma% E&.ed
boolean bStop = false; //Stop identical /,=Wy"0TJ
FileAccessI fileAccessI = null; //File Access interface ,oC={^l{
pHq{S;R2G
~3LhcU-
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ?psOj%
{ wa9'2a1?
this.sURL = sURL; B.h0" vJ
this.nStartPos = nStart; Wh#os,U$
this.nEndPos = nEnd; B)_!F`9
nThreadID = id; #-l!`\@
fileAccessI = new FileAccessI(sName,nStartPos);//定位 dY/|/eOt<K
} 46QYXmNQ}
8:;u v7p
J R8 Z6
public void run() gEcnn.(S
{ 1^n5CI|7u
while(nStartPos < nEndPos && !bStop) l:>qR/|m
{ <P?3GT/
yt]Oj*nn0K
YzforM^F
try{ >[A65q'
URL url = new URL(sURL); ymzPJ??!
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); o3kt0NuF,
httpConnection.setRequestProperty("User-Agent","NetFox"); Pf^Ly97
String sProperty = "bytes="+nStartPos+"-"; r"HbrQn
httpConnection.setRequestProperty("RANGE",sProperty); xCmI7$uQ#
Utility.log(sProperty); Z<$E.##
S)Ub/`f{s
1{;[q3a
InputStream input = httpConnection.getInputStream(); p@!@^1j=
//logResponseHead(httpConnection); y \mutm
B.CH9M
ai<MsQQ:=
byte[] b = new byte[1024]; 4{Yy05PFS
int nRead; YU ]G5\UU
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) cq@_*:~Or
{ O?4vC5x
nStartPos += fileAccessI.write(b,0,nRead); hPEp0("
//if(nThreadID == 1) O,V6hU/ *
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); S4aHce5PXA
} ~|0F?~eR7
*'AS^2'
Npf7p
Utility.log("Thread " + nThreadID + " is over!"); e!2%ku
bDownOver = true; K@$L~G
//nPos = fileAccessI.write (b,0,nRead); :<WQ;q
} N.Wdi
catch(Exception e){e.printStackTrace ();} Ma*dIwEp
} N8MlT \+r
} zw%n!wc_\
SceCucT
aJa^~*N/Aa
//打印回应的头信息 ;([tf;
public void logResponseHead(HttpURLConnection con) #pm-nU%|_j
{ +=B}R
for(int i=1;;i++) *n|0\V<
{ /i~^LITH
String header=con.getHeaderFieldKey(i); z kX-"}$8
if(header!=null) Jq+$_Uqd
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 4W//Oc@e
Utility.log(header+" : "+con.getHeaderField(header)); UmD-7Fd
else :z0>H5
break; fO|~Oz<S
} !$KhL.4P
} BtNW5'^
rM >V=|9,
w#G=Z_Tt
public void splitterStop() g0:4zeL
{ *_).UAP.
bStop = true; N>nvt.`P
} 5q_OuZ/6
u0oYb_Yv
>eG&gc@$1$
} Vg,>7?]6h
`2(R}zUHN
*A1TDc$
/* 3Llj_lf
**FileAccess.java r(in]7
*//文件访问(定位，写) )x:j5{>(
package NetFox; Y7t{4P
import java.io.*; ME10dr
%`\_l
n\"LN3
public class FileAccessI implements Serializable{ Y\z\{JW
R5;eR(24G
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 V&+$Vq
RandomAccessFile oSavedFile; L|1zHDxQ
long nPos; zI:5I@ X
$t H.np
v4>"p!_C
public FileAccessI() throws IOException "`3^MvC
{ >eTgP._
this("",0); n`T[eb~
} 5<?c_l9X^
hCvLwZ?LF
S}[:;p?F`
public FileAccessI(String sName,long nPos) throws IOException cYwC,\uF
{ j _9<=Vu
oSavedFile = new RandomAccessFile(sName,"rw"); P~ pbx
this.nPos = nPos; ;$L!`"jn
oSavedFile.seek(nPos); = 4WZr
} I;Fy k70w;
ApJf4D<V
p>tdJjnt
public synchronized int write(byte[] b,int nStart,int nLen) |wb(rua
{ *n_4Rr
int n = -1; 0#/ 6P&6
try{ /N{@g.edL
oSavedFile.write(b,nStart,nLen); TIhzMW\/K
n = nLen; J$/BH\
} @OY-(cW
catch(IOException e) })SdaZ
{ jL%}y1m?
e.printStackTrace (); ]a|;G
} b-zX3R;
:QL p`s
h}&IlDG
return n; 4"(zi5`e
} Jo$Dxa z
~[y+B0I3
y/6LMAI
} &p4<@k\L
T|2%b*/
6jo&i
/* >b?)WNk
**SiteInfoBean.java E(LE*J
*/ Byj~\QMD|
package NetFox; pDq_nx9
I8;[DP9
gK\7^95
public class SiteInfoBean { c!^}!32j)
H^:|`T|,
8vW`E_n
private String sSiteURL; //Site's URL Qb{5*>
private String sFilePath; //Saved File's Path HWOH8q{f!
private String sFileName; //Saved File's Name '\\Cpc_g
private int nSplitter; //Count of Splited Downloading File m9cT}x&j
6|cl`}g_j
S5a<L_
public SiteInfoBean() 8mLU ~P |
{//nSplitter的缺省值为5 NWK_(=n
//default value of nSplitter is 5 1^^D :tt
this("","","",5); bI(98V,t
} oz@6%3+
2<@!m@
&:K?-ac
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) K({,]<l5
{ C~V$G}mM
sSiteURL= sURL; )1 j2
sFilePath = sPath; w/6@R 4)p
sFileName = sName; P<x
this.nSplitter = nSpiltter; In M'zAhb
dwMwd@*j
Ps\^OJR
} oF xVK
MV\zwH
0%+k>(@R
public String getSSiteURL() +'.Q-
{ #?6RoFgMe
return sSiteURL; N@0scfO6<
} 1tpD|
Ngnjr7Q={T
rSn7(3e4^
public void setSSiteURL(String value) cyNLeg+O*
{ G].KJ5,y
sSiteURL = value; OhEL9"\<
} ;xwQzu%M>5
q|J]
Hp!F?J7sx
public String getSFilePath() i>2_hn_UR
{ I#U44+c
return sFilePath; `f]O
} y9)",G!
`l"~"x^Rr
{+Yo&F}n
public void setSFilePath(String value) ? Q}{&J
{ PK" C+o;:
sFilePath = value; [_n|n"M
} KK</5Aw9p
2l?J9c}Wo
Kq$1lPI
public String getSFileName() K<GCP2
{ 7I|Mq
return sFileName; UhK,H
} g\'sGt3O
S##W_OlrI
gp=0;#4 4
public void setSFileName(String value) RMK U5A7
{ #SueT"F
sFileName = value; k W,|>
} ?9+;[X
1zRO==b
odDt.gQXU
public int getNSplitter() zlE kP @)
{ 7Y/_/t~Y
return nSplitter; h%%'{^>~
} LKa_ofY
*?{)i~
;q Z2V
public void setNSplitter(int nCount) F <(Y
{ Lst5
nSplitter = nCount; YC~+r8ME$j
} h.nzkp5
} b11C3TyQT
I$$!YMm.N
+Ji dP
/* eo!z>9#.
**Utility.java !SnpesTn
*/ `|R{^Sk1o
package NetFox; "TPMSx&Ei
R-ci?7dt3
]P.S5s'
public class Utility { ^IpS 3y
Liofv4![
#]rw@c
public Utility() -Db(
{ Hogr#Sn2
fw<'ygd
"'%x|nB
} 7 UR)4dYA
/9sUp}*
//线程睡眠 Rzp-Q5@MY
public static void sleep(int nSecond) AK[c!mzx
{ - 0zo>[c/p
try{ m{~r6@
Thread.sleep(nSecond); yDPek*#^"q
} 6(.&y;
catch(Exception e) K|iNEhuc
{ OnG?@sW+4!
e.printStackTrace (); t;'__">:q
} `| fF)kI
} IySlu^a
%lujme
//日志 -Jb I7Le
public static void log(String sMsg) bcQ$S;U)
{ ~!@a
System.err.println(sMsg); nv|&|6?`oK
} N7|ctO
ST{<G
JWLQ9UX
public static void log(int sMsg) Q~jUZ-qN
{ b(wiJ&t
System.err.println(sMsg); h>4\I;Ij
} tYnNOK*|
} =T[kGg8`
zzM 'uo
nfc&.(6x<
/* ;:v:pg8qc
**TestMethod.java q?`bu:yS
*/ 1Eh(U
package NetFox; }_K7}] 1
X[R/j*K
W}Z'zU?[
public class TestMethod { vFQ'sd]C
U\+o$mU^
9%|!+!j
public TestMethod() -|g~--@Q
{ ///xx/weblogic60b2_win.exe G"wy?
try{ L\pe
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ri6_u;Ch
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Nb-;D)W;B
SiteFileFetch fileFetch = new SiteFileFetch(bean); d&F8nBIM5
fileFetch.start(); _E3*;
} -r[l{ce
catch(Exception e){e.printStackTrace ();} _L9`bzZj
G >bQlZG
;8H m#p7,
} =}F &jl
5Osx__6$t
:2}zovsdj
public static void main(String[] args) %+qD-{&
{ 525W; mu{
new TestMethod(); $0 eyp]XC\
} y^?7de}
} 3 cu`U`
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