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)); l=oVC6C
} k@~-|\ooG
for(int i=0;i<nEndPos.length-1;i++) {7wvC)WW
{ 79V5{2Y*U
nEndPos = nStartPos[i+1]; sV6A& Aw
} *"5a5.`%,
nEndPos[nEndPos.length-1] = nFileLength; d5%*^nMpY
} W(8g3
} "tark'
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w?*KO?K
//启动子线程 WU4i-@Bm8
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; GKSy|z
for(int i=0;i<nStartPos.length;i++) qh'BrYu*
{ K4yYNlY
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), +E:(-$"R
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), [0LqZ<\5
nStartPos,nEndPos,i); 10rGA=x'(
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); g?VME]:
fileSplitterFetch.start(); YUb,5Y0
} 'k67$H
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ^;3rdBprm
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 5{a( +'
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", a7|&Tbv
nEndPos = " + nFileLength); gB(W`:[
// fileSplitterFetch[nPos.length-1].start(); t/1NTa
\k=Qq(=
Yel(}Ny
//等待子线程结束 IpJv\zH7
//int count = 0; %MJ7u}
//是否结束while循环 !S!03|
boolean breakWhile = false; K)+l6Q
F"H!CJJu&
#}(Df&
while(!bStop) j*u9+.
{ S7/v,E
write_nPos(); ug,|'<G+
Utility.sleep(500); 1^#Q/J,
breakWhile = true; 5#)<rK
,rI |+
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for(int i=0;i<nStartPos.length;i++) uW~,H}E
{ E`n`#=xKR
if(!fileSplitterFetch.bDownOver) ~ p.W*skD
{ \,gZNe&Vv
breakWhile = false; ('-}"3
break; U_;J.{n
} <57l|}8
} WkySTc
if(breakWhile) w%dIe!sV
break; K=?F3tX^
W+ '}O<
}!<cph
//count++; F` 5/9?;|
//if(count>4) 25c!-.5D
// siteStop(); xO-U]%oq
} ;T{/;
So*Wk "
P&3/nL$9N
System.err.println("文件下载结束！"); >DUE8hp;<
} KBRg95E~]l
catch(Exception e){e.printStackTrace ();} nl9Cdi]o
} \seG2vw$
AV 5\W}
,e FQ}&^A
//获得文件长度 lhA s!\F
public long getFileSize() ObyuhAR
{ >_aio4j}r
int nFileLength = -1; tP Efz+1N
try{ +F~0\#d
URL url = new URL(siteInfoBean.getSSiteURL()); ^GrkIh0nL
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); z2Y_L8u2
httpConnection.setRequestProperty("User-Agent","NetFox"); ?)[zLnxc&
zt[4_;2Y
dHq )vs,L
int responseCode=httpConnection.getResponseCode(); PWk?8dL-
if(responseCode>=400) hHc^ZA
{ blfE9Oy
processErrorCode(responseCode); TjUZv1(L
return -2; //-2 represent access is error [Ql?Y$QB`4
} =tc`:!$
[%84L@:h
:#\B {)(
String sHeader; YNg\"XjJM<
du'}+rC
wyrI8UY
for(int i=1;;i++) EID)o[<
{ (~7m"?
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); gR;8ht(pd(
//Utility.log(in.readLine()); &:DCtjK
sHeader=httpConnection.getHeaderFieldKey(i); [-E{}FL|
if(sHeader!=null) (K*/Vp
{ DrCWvpudd
if(sHeader.equals("Content-Length")) f3zfRhkIk
{ V5u}C-o
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); Ld\LKwo
break; 8|5Gv
} :kb1}Wu
} AB2mt:^
else ]g>m?\'n
break; t+3
} ]_ejDN\>{V
} Mhv1K|4s
catch(IOException e){e.printStackTrace ();} hJw |@V
catch(Exception e){e.printStackTrace ();} {d1N&
%tzN@
U]V3DDN
Utility.log(nFileLength); bkr~13S{+
0'yG1qG
lh,ylh
return nFileLength; c<=`<!FS[
} 4|> rwQ~t
YN,y0t/cQ
r,2Xu
//保存下载信息（文件指针位置） ,DQGv_
private void write_nPos() dGbU{#"3s
{ a=J@yK
try{ KInUe(g<9M
output = new DataOutputStream(new FileOutputStream(tmpFile)); ZnvEv;P
output.writeInt(nStartPos.length); r5MxjuOB1
for(int i=0;i<nStartPos.length;i++) k^H0b\hYY
{ l|08
// output.writeLong(nPos); IajD;V
output.writeLong(fileSplitterFetch.nStartPos); ^M`>YOU2+
output.writeLong(fileSplitterFetch.nEndPos); R'Kt=.s<
} 2d-TU_JqX
output.close(); yz[%MXI
} Qg'c?[~W@
catch(IOException e){e.printStackTrace ();} + ,@ FxZl
catch(Exception e){e.printStackTrace ();} FU_fCL8yA
} Op`I;Q #%d
Sm$p\ORa
;_mgiKHg
//读取保存的下载信息（文件指针位置） WGH%92
private void read_nPos() b8rp8'M)
{ F>(qOH.I
try{ E%<w5d.lq
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); :PgF
int nCount = input.readInt(); VZ\O9lD
nStartPos = new long[nCount]; Z5((1J9
nEndPos = new long[nCount]; PT3>E5`Nu
for(int i=0;i<nStartPos.length;i++) Oo FgQEr@
{ (C,e6r Y
nStartPos = input.readLong(); #v{Y=$L
nEndPos = input.readLong(); `TUZZz
} Rw{$L~\
input.close(); hHcJN
} u3U4UK
catch(IOException e){e.printStackTrace ();} ?nQ_w0j
catch(Exception e){e.printStackTrace ();} )VNM/o%Q
} AT"!{Y "H
oFWt(r
{}V$`L8
private void processErrorCode(int nErrorCode) DW#Bfo
{ ]JH64~a
System.err.println("Error Code : " + nErrorCode); 1Fv8T'
} lK0s=4c{
@&;(D!_&
NwguP
//停止文件下载 M|d={o9Hp
public void siteStop() y<TOqn
{ ~e{H#*f&1/
bStop = true; =4eUAeH {w
for(int i=0;i<nStartPos.length;i++) :4|M jn
fileSplitterFetch.splitterStop(); |+98h&U~
1!vPc93 $$
2gt+l?O<PS
} ~8TF*3[}[
} UVrQV$g!
//负责部分文件的抓取 zxkM'8JC
**FileSplitterFetch.java 9CB\n
*/ ]fZ<`w8u}
package NetFox; 5y]io Jc9-
%Uy%kN_&
%,/lqcFo
import java.io.*; G8eD7%{b:)
import java.net.*; BWh}^3?l
pV7N byb4
/Y,r@D
public class FileSplitterFetch extends Thread { (ew} gJ
) V36t{
Z0$] tS
String sURL; //File URL i\)3l%AK]T
long nStartPos; //File Snippet Start Position gw^'{b
long nEndPos; //File Snippet End Position m[spn@SF
int nThreadID; //Thread's ID ~h! 13!
boolean bDownOver = false; //Downing is over bHE7yv [
boolean bStop = false; //Stop identical #jBN?Z#
FileAccessI fileAccessI = null; //File Access interface \:Za[6
*t(4 $
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException XV>@B $hu
{ _\\ -md:
this.sURL = sURL; 9cG<hX9`F
this.nStartPos = nStart; ,(N[*)G
this.nEndPos = nEnd; *)'Vvu<
nThreadID = id; v*z(@<Y
fileAccessI = new FileAccessI(sName,nStartPos);//定位 dY!u)M;~~
} "UG K8x
jAC78n,Fi@
^2S# Uk
public void run() o5!f#Y
{ r8[T&z@_
while(nStartPos < nEndPos && !bStop) dz-y}J11
{ 7&U&E|
irKIy
O("Uq../3
try{ XN;&qR^j
URL url = new URL(sURL); 19t{|w<
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); S_b/DO
httpConnection.setRequestProperty("User-Agent","NetFox"); @0NJ{
String sProperty = "bytes="+nStartPos+"-"; 0 )}$^TV
httpConnection.setRequestProperty("RANGE",sProperty); )h_8vO2
Utility.log(sProperty); ?mv:neh
MsOs{2 )2
jVWK0Zba
InputStream input = httpConnection.getInputStream(); hH>``gK
//logResponseHead(httpConnection); (=u'sn:s
wRvb8F0
.c+9P<VmC}
byte[] b = new byte[1024]; Q.Aa{d9e
int nRead; 28I^$> [
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) @Jn!0Y1_3
{ cn`iX(ZgR
nStartPos += fileAccessI.write(b,0,nRead); np9dM
//if(nThreadID == 1) ' cIEc1y
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); [f/I2
} {tiKH=&J
>IfV\w32
:"1|AJo)
Utility.log("Thread " + nThreadID + " is over!"); Bc5+ss
bDownOver = true; h6:#!Rg
//nPos = fileAccessI.write (b,0,nRead); `A@w7J'
} B?bW1
catch(Exception e){e.printStackTrace ();} pG3k
} /F)H\*
} 3Q^fVn$tk
I/6)3su%
x;s0j"`Jb
//打印回应的头信息 UL$}{2N,_
public void logResponseHead(HttpURLConnection con) d+eZub94U
{ W?woNt'n
for(int i=1;;i++) w_tJ7pz8T
{ \ 0W!4D
String header=con.getHeaderFieldKey(i); tq1CwzRX
if(header!=null) zi@]83SS#
//responseHeaders.put(header,httpConnection.getHeaderField(header)); C1kYl0zR[
Utility.log(header+" : "+con.getHeaderField(header)); V!_71x\-Q
else $sHP\{
break; QS[L~97m2M
} 942lSyix
} n2B){~vE
NoE*/!Sr
q?qC
public void splitterStop() B;>{0 s
{ ED>prE0
bStop = true; uo%P+om_}
} {^a36i
-VKS~{
}@ Z56
} Mn1Pt|_@!
Hmt^h(*/2
:}8Z@H!KkY
/* H %JaZ?(
**FileAccess.java }o4N<%/+
*//文件访问(定位，写) &Mq~T_S
package NetFox; y$FW$Ka
import java.io.*; e}/Lk5q!
MTg:dR_
NX`*%K
public class FileAccessI implements Serializable{ ^z1&8k"[^
LEMfG~Czq
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 -}O1dEn.
RandomAccessFile oSavedFile; *4+3ObA
long nPos; u0aJu
"k*PA\U
$vC1 K5sLk
public FileAccessI() throws IOException MYJg8 '[j
{ m8'C_U^89
this("",0); \$0F-=w`8
} j 8*ZF
]#7zk9
A+6 n#
public FileAccessI(String sName,long nPos) throws IOException 1) ta
{ '!l1=cZD
oSavedFile = new RandomAccessFile(sName,"rw"); ?]D"k4
this.nPos = nPos; il|1a8M2~
oSavedFile.seek(nPos); ee%fqVQ8P
} ;};wq&b#
?\C"YG69T
6qcO?U
public synchronized int write(byte[] b,int nStart,int nLen) ono4U.C9
{ a=M\MZK>
int n = -1; fP.F`V_Y
try{ qM#R0ZUIe\
oSavedFile.write(b,nStart,nLen); Y3Vlp/"rB"
n = nLen; r.4LU
} 3nZo{p:E
catch(IOException e) 0-~\ W(
{ aW>6NDq(
e.printStackTrace (); ^i:`ZfA#
} ZPbpp@,
B}PIRk@a1
LpR3BP@At
return n; 0eK*9S]
} ]\7]%(
)M)7"PC
jDQZQ NS
} rn<PR*
[IK )
jBegh9KHq
/* `uC@nJ
**SiteInfoBean.java Mbjvh2z
*/ `w]s;G[
package NetFox; OKoan$#sn
d/i`l*
lsJnI|
public class SiteInfoBean { !Q#{o^{Y~
s`0QA!G{-
8MSC.0
private String sSiteURL; //Site's URL J>/w5$h5
private String sFilePath; //Saved File's Path OF\rgz
private String sFileName; //Saved File's Name 9uGrk^<t
private int nSplitter; //Count of Splited Downloading File aG^4BpIP
wXsmn1w9
fMOU$0]$<
public SiteInfoBean() /iX+R@
{//nSplitter的缺省值为5 U\Z?taXB
//default value of nSplitter is 5 -;'1^
this("","","",5); je!-J8{
} U~pV)J
~JaAii{
92EWIHEWZ
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) V3"=w&2]K
{ rb|U;)C
sSiteURL= sURL; eM+!Y>8Y
sFilePath = sPath; Dc_yM
sFileName = sName; y~FV2$
this.nSplitter = nSpiltter; }I :OsAw
m}X`> aD/
nJo`B4'U
} |9B.mBoX
Sv +IS
*NG+L)g
public String getSSiteURL() ll C#1
{ uXKERzg
return sSiteURL; #W|'1 OX4
} 5=Di<!a;
!1ED~3/X
B#M5}QT|2
public void setSSiteURL(String value) t]YC"%[S
{ ;dJ1
sSiteURL = value; T3^GCX|!@
} k3uit+ge}
*FMMjz
QDhOhGK
public String getSFilePath() uH(f$A
{ Wr( y)D<y}
return sFilePath; ](s'L8(x
} WS`qVL]^&
#H:7@
\Rp-;.I@6
public void setSFilePath(String value) `tn{ei
{ m8o(J\]
sFilePath = value; H(Z88.OM
} sPR1?:0:
u4/kR
lb3]$Da
public String getSFileName() !Y[lQXv
{ &MCbYph,
return sFileName; +w+}b^4
} z&fwE$Nm
4/wa+Y+=vt
f>N!wgo[
public void setSFileName(String value) J%,*isEL
{ e8GEoD
sFileName = value; SgS~ {4Zx*
} CW,Wx:Y
U4b0*`o
)3>hhuaa
public int getNSplitter() Uk6HQQ
{ D"a~#^
return nSplitter; ~x]jB
} PEW=@xj2y
&FF"nE*
#~<0t(3Q
public void setNSplitter(int nCount) a+%6B_|\
{ "$2y-|
nSplitter = nCount; !0vG|C;'
} pLLGus+W
} lc~%=
y9>ZwYN
rV T{90,
/* 1f":HnLRM
**Utility.java *q-['"f
*/ F;7dt@5;
package NetFox; Z|lqb=
N-e @j4WU
6jC`8l:
public class Utility { osX8eX]\
.P7"e5ge
}x07^4$j
public Utility() 1$p2}Bf{n
{ RT.D"WvT
=AEBeiz
i;_tI#:A
} 8n*.).33
T^Ze3L]
//线程睡眠 z<##g
public static void sleep(int nSecond) -T[lx\}
{ -bSSP!f
try{ JNJ=e,O,
Thread.sleep(nSecond); \uza=e
} br":y>=,
catch(Exception e) 5a hVeY
{ 9mmCp&~Z
e.printStackTrace (); hKT
} <cqbUL
} 98uV6b~g
'gTbA?+@5
//日志 >VN5`Zlw\C
public static void log(String sMsg) 4'!c*@Y
{ q@nP}Pv&5
System.err.println(sMsg); ?6fnpGX@a
} :uK?4
=A!@6Nw
=Q+= f
public static void log(int sMsg) y*tZ !m2Gg
{ O4^8jK}
System.err.println(sMsg); s3R(vd
} p%*%n3bw
} jO1r)hw N>
nysUZB
O"c;|zCc>
/* 06N}k<10O
**TestMethod.java vfE6Ggz
*/ <F`>,Pm
package NetFox; &'}RrW-s
TTt#a6eJ
6u7?dG'4
public class TestMethod { or';A'k
Zy(W^~NT
1M 781
public TestMethod() ] 0B2# d
{ ///xx/weblogic60b2_win.exe Z3&_
try{ ~nG(5:A5g/
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); I.94v #r
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 5Drq9B9;
SiteFileFetch fileFetch = new SiteFileFetch(bean); ;bLEL"x%
fileFetch.start(); }9W4"e2)
} ~R26
catch(Exception e){e.printStackTrace ();} +L9Eqll
Gq }U|Z
'zGo?a
} I$0)Px%z
/x[jQM\
k+8q{5>A<
public static void main(String[] args) m/y2WlcRx
{ "0cID3A$
new TestMethod(); 86mp=6@
} ?`#/ 8PN
} \8 h;K>=h
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