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)); ]=2Ba<)m
} b~Op1p
for(int i=0;i<nEndPos.length-1;i++) f`.8.1Rd
{ O>wGc8Of\
nEndPos = nStartPos[i+1]; vJ7I [Z
} LgjL+w19
nEndPos[nEndPos.length-1] = nFileLength; IwKhun
} ^L+*}4Dr
} ,_r"=>?@
dZIAotHN:
H`njKKdR
//启动子线程 :mXc|W3
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ~_QZiuq&
for(int i=0;i<nStartPos.length;i++) X_ne#ZPl
{ 36*"oD=@
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 2#kR1rJP
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), dd@^e)VZB
nStartPos,nEndPos,i); 93XTumpV
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); &vLz{
fileSplitterFetch.start(); ,icgne1j
} YxlV2hcX;
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), EQSOEf[
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ,@tkL!"9q
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", *$Z}v&-0k
nEndPos = " + nFileLength); iN"kv
// fileSplitterFetch[nPos.length-1].start(); JC(rSs*
4vT!xn
VJDF/)X3$
//等待子线程结束 >E|@3g +2
//int count = 0; GRB/N1=
//是否结束while循环 zu5'Ex`gQa
boolean breakWhile = false; h +.8Rl
^&zwO7cS
M")JbuI
while(!bStop) @H= d8$
{ AMG}'P:
write_nPos(); oN)l/"%C7/
Utility.sleep(500); =SB#rCH
breakWhile = true; {^i73}@O
S 3Tp__
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for(int i=0;i<nStartPos.length;i++) hF s:9
{ 01g=Cg
if(!fileSplitterFetch.bDownOver) 5DK>4H:
{ K}tl,MMU
breakWhile = false; /1F%w8Iqh
break; i6?,2\K
} %%`Nq&'
} l_hM,]T0
if(breakWhile) P,k~! F^L
break; swYlp
8*!<,k="9
mTz %;+|L
//count++; 0;2i"mzS\
//if(count>4) Tz4,lwuWX7
// siteStop(); uz-,)
} +D[|L1{xb
R 5-q{
<k<K"{
System.err.println("文件下载结束！"); KtchKpv
} =dx!R ,Bw
catch(Exception e){e.printStackTrace ();} E0!}~Z)
} vH%AXzIA
<vJPKQ`=:
btHN
//获得文件长度 seC]=UJh#>
public long getFileSize() eqU2>bIf
{ VR ^qwS/
int nFileLength = -1; RbzSQr>a\
try{ /:3:Ky3
URL url = new URL(siteInfoBean.getSSiteURL()); 0?KXQD
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); f]`#BE)V
httpConnection.setRequestProperty("User-Agent","NetFox"); n0F.Um
FRd!UqMXY
(+68s9XS7
int responseCode=httpConnection.getResponseCode(); px %xoY
if(responseCode>=400) 26PUO$&b.
{ X1&Ug^
processErrorCode(responseCode); Qz\yoI8JA,
return -2; //-2 represent access is error 11[[HkX@
} reR><p
v#0F1a?]D
8^\}\@
String sHeader; {STOWuY
h[#Lg3
u.sF/T=6f
for(int i=1;;i++) R*a5bKr
{ d9>*a$x;/
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); k"D6Vyy`
//Utility.log(in.readLine()); 5Ds/^fA
sHeader=httpConnection.getHeaderFieldKey(i); 0D/u`-
if(sHeader!=null) (|)`~z
{ c[\ :^w^I6
if(sHeader.equals("Content-Length")) lffp\v{w
{ Hy^Em
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ;*1bTdB5a
break; x;)bp7
} KY34Sc
} ]E'BFon
else XI:8_F;Q
break; \95qH,w)T
} =F'p#N0_2
} -1iKeyyA
catch(IOException e){e.printStackTrace ();} Ec IgX_\
catch(Exception e){e.printStackTrace ();} 9pUvw_9MY
fZ1v|
:f%FM&b
Utility.log(nFileLength); %E#OUo[y/
#<0Yx9Jh.
,Tc3koi
return nFileLength; e8g"QDc
} Lh3>xZy"-z
`Fa49B|`D
f2Zi.?``H
//保存下载信息（文件指针位置） 28FC@&'H
private void write_nPos() cKuU#&FaV
{ kR$>G2$!
try{ !+T\}1f7d
output = new DataOutputStream(new FileOutputStream(tmpFile)); OLh`R]Sd
output.writeInt(nStartPos.length); |$"2R3
for(int i=0;i<nStartPos.length;i++) !$Aijd s5
{ ]T|9>o!
// output.writeLong(nPos); Xou1X$$z
output.writeLong(fileSplitterFetch.nStartPos); )OQhtxK
output.writeLong(fileSplitterFetch.nEndPos); WeDeD\zy
} maAZI-H{
output.close(); L1=3_fO
} L08>9tf`
catch(IOException e){e.printStackTrace ();} Y$xO&\&)
catch(Exception e){e.printStackTrace ();} d\aKGq;8C
} u>c\J|K_V
9rXbv4{
^2f'I iE
//读取保存的下载信息（文件指针位置） 7jvy]5y8&~
private void read_nPos() 8 2qf7`
{ NbOeF7cq+
try{ L#sw@UCK
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); \{r-e
int nCount = input.readInt(); Ft%HWGE
nStartPos = new long[nCount]; t`NZ_w /
nEndPos = new long[nCount]; !wiW#PR
for(int i=0;i<nStartPos.length;i++) U |I>CDp
{ $jT&]p
nStartPos = input.readLong(); 2WQKj9iyN
nEndPos = input.readLong(); A{\#.nC/z
} .N2yn`
input.close(); HR)Dz~Obw
} Oop5bg
catch(IOException e){e.printStackTrace ();} VD[x}8ei
catch(Exception e){e.printStackTrace ();} jv$Y]nf
} }$M 2XF
'=MaO@ @
fxfzi{}uj
private void processErrorCode(int nErrorCode) 5`qt82Qm
{ ,XT#V\qne
System.err.println("Error Code : " + nErrorCode); nk.Y#+1)
} A4LGF
Z$qFjWp
3t<XbHF9
//停止文件下载 U'^AJ2L8
public void siteStop() i0F.c\
{ [h>|6%sW
bStop = true; [A$5~/Q{U1
for(int i=0;i<nStartPos.length;i++) &v!=\Fig4
fileSplitterFetch.splitterStop(); pR_cI]{=SA
FTM(y CN
KrOoxrDcp
} dw %aoe
} f[,9WkC
//负责部分文件的抓取 %Q]u_0P*
**FileSplitterFetch.java lfjY45=
*/ yXU-@~
package NetFox; eXJt9olI
5dffFe
]zp5 6U|xa
import java.io.*; 3:Bwf)*
import java.net.*; !sda6?&
B$~oZ'4v
whb|N2
public class FileSplitterFetch extends Thread { DLMG<4Cd~
g\MHv#v*k
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String sURL; //File URL %bI(
long nStartPos; //File Snippet Start Position 36>pa
long nEndPos; //File Snippet End Position z0J$9hEg89
int nThreadID; //Thread's ID ^NJ]~h{n$
boolean bDownOver = false; //Downing is over e&[gde(
boolean bStop = false; //Stop identical rkhQoYZ[
FileAccessI fileAccessI = null; //File Access interface 8 vNgePn
eUQ.,mP
=4GJYhj
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException "|W .o=R
{ mhnjYK9
this.sURL = sURL; |\Nj
this.nStartPos = nStart; gLv|Hu7
this.nEndPos = nEnd; ;/i"W
nThreadID = id; vQrce&
fileAccessI = new FileAccessI(sName,nStartPos);//定位 Ta#vD_QP
} rQiX7
EubR]ckB
SNP.n))
public void run() $q*kD#;mh
{ -1Y9-nn[m
while(nStartPos < nEndPos && !bStop) gyH'92ck
{ pT]M]/y/:
&pwSd
#!p=P<4M
try{ 6cof Zc$
URL url = new URL(sURL); >}QRMn|@H
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); {#q']YDe`
httpConnection.setRequestProperty("User-Agent","NetFox"); y e!Bfz>
String sProperty = "bytes="+nStartPos+"-"; EM/NT/
httpConnection.setRequestProperty("RANGE",sProperty); f@l6]z{.L
Utility.log(sProperty); D|I(2%aC
kTQ:k }%B
A7U'>r_.
InputStream input = httpConnection.getInputStream(); /nXp5g^6(
//logResponseHead(httpConnection); &{QB}r
&SS"A*xg
Du3OmXMk
byte[] b = new byte[1024]; BqZ^I eC$
int nRead; #QJ mAA
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Z:f0>
{ Z&8 7Aj
nStartPos += fileAccessI.write(b,0,nRead); GF~^-5
//if(nThreadID == 1) ?7-#iC`
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); pM~Xh ]/
} ];Whvdnv
JV'd!5P
/=Ug}%.
Utility.log("Thread " + nThreadID + " is over!"); P# 2&?.d\
bDownOver = true; 2=ZR}8}9Q:
//nPos = fileAccessI.write (b,0,nRead); Z+ubc"MVb
} Cus=UzL
catch(Exception e){e.printStackTrace ();} m%V+px
} ZWMX!>o<
} WrbDB-uM
J#Fe"
}]vj"!?a
//打印回应的头信息 }@yvw*c
public void logResponseHead(HttpURLConnection con) +C7 1".i-
{ 7=XQgbY/
for(int i=1;;i++) /R#-mY
{ }yqRz6=YB
String header=con.getHeaderFieldKey(i); J#*Uf>5NY
if(header!=null) G],+?E_,
//responseHeaders.put(header,httpConnection.getHeaderField(header)); O<4i)Lx2
Utility.log(header+" : "+con.getHeaderField(header)); 2>Kq)Ii
else 1_:1cF{w
break; UwtOlV:G{
} Bp\io$(%
} wo2^,Y2z+
g$VcT\X
o^~6RZ
public void splitterStop() Gb61X6
{ &Pxt6M\d
bStop = true; 'R*gSqx~
} /Nq!^=
~J2-B2S!
yb/< 7
} W9 y8dw.
yp5*8g5
3M{!yPlj
/* rP ;~<IxEr
**FileAccess.java (Wr;:3i
*//文件访问(定位，写) 'R_U,9y`
package NetFox; D,xWc|V
import java.io.*; qt]QO1pAd
v,vTRrpK
j>&n5?
public class FileAccessI implements Serializable{ [2w3c4K
y- k?_$M
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 w|WZEu:0|
RandomAccessFile oSavedFile; ^a; V-US
long nPos; GQqw(2Ub}
qh$D;t1=
{#QFDA
public FileAccessI() throws IOException 2`5(XpYe
{ 7tAWPSwf
this("",0); *" <tFQ
} {N5g52MN
7~\Dzcfk"P
NOyLZa'
public FileAccessI(String sName,long nPos) throws IOException QXJD'c
{ ZC"6B(d
oSavedFile = new RandomAccessFile(sName,"rw"); ]+0-$t7Y
this.nPos = nPos; +^YV>;
oSavedFile.seek(nPos); _if&a'
} ?y<n^`
XeDU ,
3+A 0O%0*
public synchronized int write(byte[] b,int nStart,int nLen) t)XV'J
{ ORQGay
int n = -1; iN<5[ztd
try{ 6?*iIA$b
oSavedFile.write(b,nStart,nLen); ]p'Qk
n = nLen; N["c*=x
} ZfT%EPoZ:
catch(IOException e) -Qnnzp$]
{ nWFp$tJ/R
e.printStackTrace (); mMN oR]
} lNsPwyCoj
I-/PzL<W P
y=h2_jt
return n; vCH>Fj"7
} ^e@c Ozt
6}iIK,Om
gp-wlu4
} P05_\ t
sbK0OA
ccD+o$7LT
/* Xz]}cRQ[
**SiteInfoBean.java 7]e]Y>wZap
*/ 6/4OFvL1
package NetFox; "vLqYc4$
nOQ+oqM<
mf}?z21vD
public class SiteInfoBean { :NbD^h)R
O.rk!&N
v@>hjie
private String sSiteURL; //Site's URL P]Gsc
private String sFilePath; //Saved File's Path *\VQ%_wg
private String sFileName; //Saved File's Name XQj`KUO@
private int nSplitter; //Count of Splited Downloading File 5\|[)~b
DP;B*s4{U
\!cqeg*53
public SiteInfoBean() 8.-PQ
{//nSplitter的缺省值为5 aF'Ik XG d
//default value of nSplitter is 5 g?=B{V
this("","","",5); }d.R=A9L
} $,i:#KT`
K:'pK1zy
FC]? T
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) *3"C"4S
{ 9HTb
sSiteURL= sURL; 00;=6q]TA
sFilePath = sPath; $ya#-pi`;
sFileName = sName; {g/\5Z\b
this.nSplitter = nSpiltter; `dL9sfj>
E/U1g4S
t:=Ui/!q
} Mqc[IAcd]
Kq{s^G
f7s]:n*Ih
public String getSSiteURL() P\2QH@p@t
{ ]-* }-j`
return sSiteURL; 2YwV}
} 5j]}/Aq
{xM%3
N#,4BU
public void setSSiteURL(String value) k(^zhET
{ HwU \[f
sSiteURL = value; *39sh[*}
} 3N]pN<3@
_&F6As !{
/o|@]SAe.
public String getSFilePath() e'\I^'`!M
{ p~3CXmUc~
return sFilePath; ; $y.+5 q
} Ro-Mex2
.fjM9G#
a3O_8GU
public void setSFilePath(String value) ~7~nU>Vv
{ sS-5W-&P{T
sFilePath = value; c&0IJ7fZG
} Pi8U}lG;
gpw(j0/Fs
/u #9M {
public String getSFileName() tY[y?DJ
{ *\joaw
return sFileName; l,v:[N
} Qy6Avw/$
,%KB\;1mn'
(j-(fS
public void setSFileName(String value) >Mvt;'c
{ ^2mXXAQf7^
sFileName = value; }>Os@]*'^(
} w:umr#
*:&fw'vd,
@#T?SNIL5
public int getNSplitter() 'm2,7]
{ 5T
return nSplitter; ?L'k2J
} S>"dUM
,#c-"xY
5X`.2q=d
public void setNSplitter(int nCount) 7PisX!c,h
{ C&5T;=<jKO
nSplitter = nCount; y!v$5wi
} @{nT4{
} Vm6^'1CY
u*9C(je
MiSFT5$v6
/* Ab(bvS8r$
**Utility.java Cog:6Gnw
*/ c3 wu&*p{
package NetFox; tXp)o>"
2XI%4
[{zekF~)@
public class Utility { +6;OB@
w1KQ9H*
r},|kb
public Utility() &pmJ:WO,h
{ hqBwA1](a
|RjjP 7
R 7{rY
} :ZzG5[o3
O!j@8~='
//线程睡眠 sP+S86 u
public static void sleep(int nSecond) BFEo:!'F
{ P{qn@:
try{ 7P\sn<
Thread.sleep(nSecond); FcWu#}.p}
} B[$SA-ZHi
catch(Exception e) Lte\;Se.tu
{ ';lO[B
e.printStackTrace (); }>OE"#si
} QU#/(N(U#T
} '8Gw{&&
R-h7c!ko
//日志 Tl1?5
public static void log(String sMsg) ~]yqJYiid^
{ my} P\r.
System.err.println(sMsg); L`Ic0}|lzy
} Z7f~|}
G6J3F
ILVbbC`D
public static void log(int sMsg) X:e'@]Z)?
{ N&GcWcq
System.err.println(sMsg); 3{c&%F~!
} UG!&n@R
} ;{ezK8FJ}@
HwGtLeB"
jxoEOEA
/* 9z-"JnM
**TestMethod.java pTN_6=Y"
*/ zCQv:.0L
package NetFox; *o>E{
%kUJ:lg;d
j=gbUXv/
public class TestMethod { EP8LJzd"
mb/3 #)
O^<6`ku
public TestMethod() P9'5=e@jB
{ ///xx/weblogic60b2_win.exe <T}#>xHs3
try{ O:U@m@7
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); \vT8 )\
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); h\dIp`H
SiteFileFetch fileFetch = new SiteFileFetch(bean); h!Q>h7
fileFetch.start(); _AO0:&
} 'v,W gPe
catch(Exception e){e.printStackTrace ();} =DCQ!02
/# eBDo
Ltj}>.+
} l-Xxv
RS:0xN\JN
MVj@0W33m
public static void main(String[] args) k]JLk"K
{ s R~&S))
new TestMethod(); %z.G3\s0
} %z2nas$$g
} IM#+@vv
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