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)); IM}T2\tZ}
} #[C|%uq
for(int i=0;i<nEndPos.length-1;i++) 8l0%:6XbI
{ gd-4hR
nEndPos = nStartPos[i+1]; n|Vs27
} a= ;7
nEndPos[nEndPos.length-1] = nFileLength; &96I4su
} #Na3eHT
} tWD~|<\. )
d>}pz
"d>{hP
//启动子线程 r}MXXn,f
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; `UL#g![J
for(int i=0;i<nStartPos.length;i++) "?hEGJ;m"
{ bWo-( qxq
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 2c@R!*
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 5bR;R{:x
nStartPos,nEndPos,i); /cUcfe#X
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); (X@JlAfB
fileSplitterFetch.start(); 0:R}
} .@ZqCH
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), h #Od tc1)
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); y.26:c(
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", =O1N*'e
nEndPos = " + nFileLength); ngj=w;7~+
// fileSplitterFetch[nPos.length-1].start(); k!b\qS~Q
Mb=vIk{Bf
n;)!N
//等待子线程结束 snOd 3Bw
//int count = 0; v-J*PB.0p
//是否结束while循环 ;(fDR8
boolean breakWhile = false; Q5b?- P
h.ojj$f,
i)g=Lew
while(!bStop) mK5<;$
{ |\%[e@u
write_nPos(); \B8tGog
Utility.sleep(500); nVko]y
breakWhile = true; KlDW'R$
uuHR!
X90VJb]
for(int i=0;i<nStartPos.length;i++) )uiYu3 I
{ o {Sc
if(!fileSplitterFetch.bDownOver) \:]Clvc
{ VG^*?62
breakWhile = false; r5> FU>7'
break; oE[wOq+
} j<>E Fd
} #ok1qT9_
if(breakWhile) F]\(p=U.
break; jt?4raNW
!*ct3{m
> $DMVtE0
//count++; M.))UKSF
//if(count>4) mufi>}
// siteStop(); /Pv d[oF
} <61T)7
Vrzx;V%
OF&{mJH"g'
System.err.println("文件下载结束！"); RiqYC3Ka
} 9&fS<Hk
catch(Exception e){e.printStackTrace ();} T_|%nF-+
} '8K5=|!J
"i_I<?aGB
~+}w>jIm{|
//获得文件长度 t=o0 #jo
public long getFileSize() lxx)l(&
{ qk;*$Q
int nFileLength = -1; <|[G=GA\S!
try{ 5drc8_fZ
URL url = new URL(siteInfoBean.getSSiteURL()); @H2c77%
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); DW&%"$2
httpConnection.setRequestProperty("User-Agent","NetFox"); CRf!tsj@
F]DRT6)
iZ %KHqG
int responseCode=httpConnection.getResponseCode(); "{1`~pDj?
if(responseCode>=400) 8TGO6oY+=
{ AVf'"~?
processErrorCode(responseCode); UjxEbk5>^
return -2; //-2 represent access is error YyEW}2
} 8+K=3=05#U
v7&oHOk!
u:AKp<'
String sHeader; xDU>y
lx$]f)%~
'QW/TJ=7r
for(int i=1;;i++) 6x|"1 G{
{ '8\7(0$c
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); V/5.37FSb
//Utility.log(in.readLine()); CZ"~N`
sHeader=httpConnection.getHeaderFieldKey(i); P1KXvc}JGe
if(sHeader!=null) X-2rC
{ GSo&$T;B6
if(sHeader.equals("Content-Length")) "} =RPc%9
{ 7Mq4$|qhD
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); q)vdDdRe_
break; zmd,uhNc:
} )a"rj5~-
} X^;[X~g
else %;ZWYj`]n
break; yN}upYxp
} FN jT?*
} Cq\1t
catch(IOException e){e.printStackTrace ();} +TzZ
catch(Exception e){e.printStackTrace ();} hbl%<ItI49
(1pI#H"f9
9D@ $Y54
Utility.log(nFileLength); ML@-@BaN
i4;`dCT|A
rP$vZ^/c
return nFileLength; ${I$@qq83
} @!k\Ivd
xuBXOr4"P
5@l[!Jl0k
//保存下载信息（文件指针位置） ,Vb;2
private void write_nPos() GZJIIP#
{ l{q$[/J~)
try{ ]gHxvT\E
output = new DataOutputStream(new FileOutputStream(tmpFile)); K5l#dl_T
output.writeInt(nStartPos.length); %B9iby8)1
for(int i=0;i<nStartPos.length;i++) #m>Rt~(,S
{ :lf;CT6$
// output.writeLong(nPos); $7M/rF;N5X
output.writeLong(fileSplitterFetch.nStartPos); ~DY5`jV
output.writeLong(fileSplitterFetch.nEndPos); d'j8P
} CUJP"u>8M
output.close(); :eIPPh|\
} &XG k
catch(IOException e){e.printStackTrace ();} >!u@>
catch(Exception e){e.printStackTrace ();} 1K(a=o[Ce
} S}fU2Wi
&G63ReW7 @
"s-e)svB
//读取保存的下载信息（文件指针位置） MtE18m"z
private void read_nPos() 9gjI;*(z1
{ BC!n;IAe
try{ MV8Lk/zd?A
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); WH:[Y7D
int nCount = input.readInt(); cfZG3"
nStartPos = new long[nCount]; KKMzhvf]#
nEndPos = new long[nCount]; epz'GN]V
for(int i=0;i<nStartPos.length;i++) tF:'Y ~3 p
{ J6m`XC
nStartPos = input.readLong(); -anLp8G*
nEndPos = input.readLong(); BPf;!.
} Y)D~@|D,
input.close(); `v2]Jk<
} 4a'O#;ho
catch(IOException e){e.printStackTrace ();} 9iMQq40
catch(Exception e){e.printStackTrace ();} ?Q$LIoR
} >)5=6{x
2 uuI_9 "^
>y P`8Oq[
private void processErrorCode(int nErrorCode) +a'QHtg
{ D+$k
System.err.println("Error Code : " + nErrorCode); TTNgnP
} -KzU''
RX]x3-
G`!ff
//停止文件下载 !: e0cV
public void siteStop() dU!`aPL?
{ 'vgO`
bStop = true; NF?FEUoxz
for(int i=0;i<nStartPos.length;i++) ,p(4OZz5,
fileSplitterFetch.splitterStop(); sU7>q}!
>;E[XG^
TF\<`}akX
} sOyWsXd+R'
} iz|mJUx
//负责部分文件的抓取 w1zI"G~4/Q
**FileSplitterFetch.java |.bp
*/ TmN}TMhZ
package NetFox; >{DHW1kF?
.3;bUJ1
@G/':N
import java.io.*; kBPFk t2
import java.net.*; m7:E73:
'WqSHb7
%}z/_QZ
public class FileSplitterFetch extends Thread { xP@VK!sc
jgiP2k[Xom
v\9:G
String sURL; //File URL ETu7G5?
long nStartPos; //File Snippet Start Position o?G^=0T
long nEndPos; //File Snippet End Position KR
int nThreadID; //Thread's ID ~;ink
boolean bDownOver = false; //Downing is over Ru%: z>Y
boolean bStop = false; //Stop identical K;2]c3T
FileAccessI fileAccessI = null; //File Access interface IBwquw+
0m5Q;|mH
-25#Vh
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException K#"@nVWJ.m
{ eO,
this.sURL = sURL; E(G=~>P
this.nStartPos = nStart; Fa(}:Ug
this.nEndPos = nEnd; `I$qMw,@
nThreadID = id; ?e|'I"
fileAccessI = new FileAccessI(sName,nStartPos);//定位 rT`D@ I
} v}6YbY Tq
#Id.MLHxA_
1SBc:!2
public void run() ':,6s
{ )k&pp^q\
while(nStartPos < nEndPos && !bStop) ujcS>XN,1
{ fgxsC7P$
c$f|a$$b
`R@24 )
try{ lY}mrb
URL url = new URL(sURL); $XS0:C0
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); @4:cn
httpConnection.setRequestProperty("User-Agent","NetFox"); uTJi }4cw
String sProperty = "bytes="+nStartPos+"-"; D#%J||
httpConnection.setRequestProperty("RANGE",sProperty); ?o0#h
Utility.log(sProperty); dRZor gar
< %Qw dEO
FV/xp}nz
InputStream input = httpConnection.getInputStream(); da@y*TO#i
//logResponseHead(httpConnection); wAHb5>!
MCma3^/1
H+zn:j@~L
byte[] b = new byte[1024]; h3;Ij'
int nRead; M3Kpp_d_!
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ErC~,5dj;n
{ l,/q#)5[
nStartPos += fileAccessI.write(b,0,nRead); 3&*0n^g
//if(nThreadID == 1) rL URP2~
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ^F*)Jq
} hoC}@8_
@"9y\1u
e,E;\x &
Utility.log("Thread " + nThreadID + " is over!"); "xdJ9Z-B
bDownOver = true; xsRMF&8L
//nPos = fileAccessI.write (b,0,nRead); /3%]Ggwe
} /2u;w!oi.
catch(Exception e){e.printStackTrace ();} ilK8V4k<T)
} |PN-,f{-
} |xzqYu?o
+!POKr
9\)NFZ3Mz
//打印回应的头信息 [[D}vL8d
public void logResponseHead(HttpURLConnection con) :0T]p"y4
{ "!)8bTW
for(int i=1;;i++) ,|I\{J #C
{ We#*.nr{3Z
String header=con.getHeaderFieldKey(i); ^J>28Q\S
if(header!=null) ~E^EF{h
//responseHeaders.put(header,httpConnection.getHeaderField(header)); !U`T;\,v5
Utility.log(header+" : "+con.getHeaderField(header)); p)ZlQ.d#Y
else mUy/lo'4
break; Ao96[2U6
} jn\\,n"6
} JXj`
VhSKtD1
zi>f436-
public void splitterStop() ~s^&*KaA
{ [ur/`
bStop = true; mC~W/KReA
} B4R,[WE"
j~DoMP5Ls
pq5)Ug
} w]yLdfi!
l%Sz6
tzpGKhrk6
/* jo<sN
**FileAccess.java N5/TV%u
*//文件访问(定位，写) 0'97af
package NetFox; @YwaOc_%
import java.io.*; D~f.)kkC4
.M>u:,v
`?JrC3
public class FileAccessI implements Serializable{ #<'/sqL
N83RsL "}_
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 :o}7C%Q8
RandomAccessFile oSavedFile; x6DH0*[.
long nPos; =hl-c
\f66ipZK*
PLLlo~Bb
public FileAccessI() throws IOException >4EcV1y
{ flLmZ1"
this("",0); wuYo@DDU#
} q/OraPAB
cJ8*[H<NV
xC;$/u%'
public FileAccessI(String sName,long nPos) throws IOException N[pk@M\vX
{ tW=0AtZl]
oSavedFile = new RandomAccessFile(sName,"rw"); N=I5MQG
this.nPos = nPos; i0AC.]4e"
oSavedFile.seek(nPos); BC$In!
} /v!H{Zw=c
D"x~bs?V\
rW\~sTH
public synchronized int write(byte[] b,int nStart,int nLen) !Rb7q{@>
{ [/#n+sz.A
int n = -1; %7|qnh6
try{ CKBi-q FH
oSavedFile.write(b,nStart,nLen); Mxr#
n = nLen; {iQ<`,)Y
} /asyj="N7
catch(IOException e) coLn};W2
{ t*}<v@,
e.printStackTrace (); 8=nm`7(]
} +^69>L2V
JAiV7v4&R
G,"$Erx
return n; 4|+ |L_
} w@:o:yLS
)d.7xY7!
gdG: &{|x
} ))KsQJ"V
+$ -#V
^cAJCbp7
/* gSe{S
**SiteInfoBean.java moo>~F _^
*/ 41uSr 1
package NetFox; HdnSs0/
c//W#V2Q
0~S<}N
public class SiteInfoBean { mMjVbeh[
3o^V$N.
57MoO
private String sSiteURL; //Site's URL \U-5&,fP
private String sFilePath; //Saved File's Path &YMVoyVD
private String sFileName; //Saved File's Name Y-{spTI
private int nSplitter; //Count of Splited Downloading File G/ ^|oJ/G
l|up3A3)
#&5\1Qu
public SiteInfoBean() r=[}7N
{//nSplitter的缺省值为5 aEM#V
//default value of nSplitter is 5 &GZR-/
this("","","",5); R;.WOies4
} -"nYCF
L"-&B$B:
./g#<
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) PQ(%5c1e
{ *|3z($*U]
sSiteURL= sURL; 6?iP z?5
sFilePath = sPath; -'VT
sFileName = sName; Lul?@>T
this.nSplitter = nSpiltter; VN".NEL
Ce)Wvuh
UD(#u3z
} `dNb%f>
Q$zlxn 7\
vSL{WT]m
public String getSSiteURL() d!X?R}
{ ]s SoIT
return sSiteURL; HWU{521
} ZT8j9zs
mT9\%5d3
.KLuGb3JJ
public void setSSiteURL(String value) t&uHn5
{ 5.E 2fX
sSiteURL = value; $G}Q}f
} 7U7 i2 4
t8+93,*B
E,$uNw']
public String getSFilePath() n)H0;25L
{ )K6{_~Kc\
return sFilePath; '[E_7$d
} l`]!)j|+
M*HG4(n0
!Ch ya
public void setSFilePath(String value) e_;6UZ+
{ =w8 YZs8w
sFilePath = value; Lgfr"{C
} srkOad
gA|j\T{c
}.vy|^X
public String getSFileName() ]z%9Q8q'
{ 1mV0AE538
return sFileName; 6;*(6$;
} :F\f}G3
E;Hjw0M'k
{cI<4><
public void setSFileName(String value) w6Q]?p+
{ )1,&YJM*6l
sFileName = value; cOgtBEhn
} iy"Kg]
]*h}sn=
ATHz~a
public int getNSplitter() qsRh ihPX
{ Sx"I]N
return nSplitter; d!:SoZ
} `y#C%9#
Qa%SvA@R
4\3t5n
public void setNSplitter(int nCount) jayoARUB
{ :<gk~3\
nSplitter = nCount; GZt] 38V)g
} Jx<
} -tdG}Gu
)]R?v,9*D
tK H!xit
/* Zv\b`Cf}
**Utility.java WGx>{'LJ
*/ #w@Pa L iS
package NetFox; aB)DX
Z(eSnV_RL
U*TN/6Qy.
public class Utility { ~4<3`l=A
sCl,]g0{
IycxRig
public Utility() QR'g*Bro
{ kDh(~nfj
+GS=zNw#
;gnr\C*G
} 5aNDW'z`f
lg+g:o
//线程睡眠 Sq,ty{j2%
public static void sleep(int nSecond) 4vS!99v)
{ >6 #\1/RP
try{ ]Dg0@Y
Thread.sleep(nSecond); E}=NZqOB!
} O;BPd:<
catch(Exception e) Gf\_WNrSE+
{ $O8V!R*
e.printStackTrace (); v!xrUyN~m
} ~S!kn1&O
} &:*+p-!2<
%#a%Luq
//日志 Hrnql
public static void log(String sMsg) j.}V~Sp*
{ Nk4_!
System.err.println(sMsg); n #I}!x>2
} Kj 8 W
f:5/y^M&
5#\p>}[HG
public static void log(int sMsg) u_8 22Z
{ NGUGN~p
System.err.println(sMsg); AHY)#|/)
} y3]"H(
} %ko 8P
:<8V2
8v 1%H8
/* HPKyAcS\
**TestMethod.java vq7%SEkES
*/ 7F:;3c
package NetFox; -%l,Zd9
Yj\yO(o/
|l(lrJ{
public class TestMethod { U(4_X[qD
KBe {
! hr@{CD
public TestMethod() reJ?38(
{ ///xx/weblogic60b2_win.exe 0 _}89:-
try{ x{V>(d'p
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); |7x^@i9w
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); [frD L)
SiteFileFetch fileFetch = new SiteFileFetch(bean); R}9jgB
fileFetch.start(); 2z# @:Q
} EsB'nf r
catch(Exception e){e.printStackTrace ();} 2(//slP
$yFuaqG`Wo
KocXSh U
} Qmx~_
^3o8F
no6]{qn=6
public static void main(String[] args) {; cB?II
{ WC*:\:mh
new TestMethod(); e*6` dz@
} X]"OW
} 1>x@1Mo+K
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