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)); QXu[<V
} !$NQF/Ol
for(int i=0;i<nEndPos.length-1;i++) WJJmM*>JW
{ OF}."a
nEndPos = nStartPos[i+1]; } fa
} p%R+c
nEndPos[nEndPos.length-1] = nFileLength; +'/C(5y)0X
} ~ <36vsk
} I@oSRB
WF_v>g:g
mclV"?
//启动子线程 ~8&P*oFC
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; y?V^S;}&]
for(int i=0;i<nStartPos.length;i++) oj/#wF+
{ @#=yC.s
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), KV)if'
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), x1h&`QUP
nStartPos,nEndPos,i); X[!S7[d-y
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Dz&,g+>$J
fileSplitterFetch.start(); R=<%!
} Bg[_MDWc-P
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 6e S~*
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); '|<r[K
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", `mH]QjAO
nEndPos = " + nFileLength); &hUEOif
// fileSplitterFetch[nPos.length-1].start(); w^9< I]
b<%c ]z
aL*}@|JL"
//等待子线程结束 Qz89=#W
//int count = 0; DheQcM
//是否结束while循环 &e78xtA{
boolean breakWhile = false; D |=L)\
&2Ef:RZF
=W&m{F96
while(!bStop) S['cX ~
{ *+XiBho
write_nPos(); :dQRrmM
Utility.sleep(500); )~Gn7
breakWhile = true; l3*GQ~m7
*\@RBJGF
mE=Ur
for(int i=0;i<nStartPos.length;i++) S.{
{ K$:+]fJK
if(!fileSplitterFetch.bDownOver) &6vWz6!P
{ :+ mULUi
breakWhile = false; B&7NF}CF2
break; 7l ,f
} @q`T#vd
} 4*L*"vKa
if(breakWhile) , @!X!L
break; !^8X71W|
9]{va"pe7
93Zij<bH?e
//count++; mP=[h |a$r
//if(count>4) BY&{fWUo
// siteStop(); ^|=P9'4Th
} _n/73Oh
fL#r@TB-s
YQ.ci4.f
System.err.println("文件下载结束！"); :|$cG~'J
} V2|By,.
catch(Exception e){e.printStackTrace ();} vcsSi%M\U
} "*t0 t
j!y9E~Zz
:p,|6~b$
//获得文件长度 ya{`gjIlW
public long getFileSize() ;c>"gW8
{ .k-6LR
int nFileLength = -1; j RcE241
try{ kG{};Vm
URL url = new URL(siteInfoBean.getSSiteURL()); Y9|!=T%
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); d:w/{m%#
httpConnection.setRequestProperty("User-Agent","NetFox"); gS'7:UH,
>~Xe` }'
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int responseCode=httpConnection.getResponseCode(); M.6uWwzQR
if(responseCode>=400) ?AD-n6
{ 0j;ZPqEf3
processErrorCode(responseCode); w/O'&],x
return -2; //-2 represent access is error E N%{ $
} ;Ce?f=4
e[?,'Mp9
h]L.6G|hEN
String sHeader; Ws7fWK;
m[^)Q9o}
.d}yQ#5z
for(int i=1;;i++) 4sntSlz)~k
{ 2$kB^g!:o
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); bhGRD{=
//Utility.log(in.readLine()); _/z_ X
sHeader=httpConnection.getHeaderFieldKey(i); :IBP "
if(sHeader!=null) \O4s0*gw
{ ]hS<"=oj
if(sHeader.equals("Content-Length")) >zDQt7+g;
{ s+v9H10R
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); VBQAkl?(}4
break; ;y. ;U#O
} \Cu=Le^
} k(pJVez
else U3z23LgA
break; YJMs9X~3
} bL`\l!qQx;
} Exqz$'(W9
catch(IOException e){e.printStackTrace ();} 7%EIn9P
catch(Exception e){e.printStackTrace ();} wM4{\ f\
qqe"hruFJ
$kxP5q%9
Utility.log(nFileLength); $u.rO7)
(*P`
;akW i]
return nFileLength; 3vcyes-U
} Ahl&2f\
OblHN*
O|+ZEBP
//保存下载信息（文件指针位置） :e=7=|@7
private void write_nPos() i9zh X1#
{ >J3mta3
try{ \XmplG:
output = new DataOutputStream(new FileOutputStream(tmpFile)); |9%~z0
output.writeInt(nStartPos.length); {q`8+$Z;
for(int i=0;i<nStartPos.length;i++) >n3GvZ5%
{ ] 1pIIX}
// output.writeLong(nPos); V\x'w*FP
output.writeLong(fileSplitterFetch.nStartPos); 2,q*8=?{6P
output.writeLong(fileSplitterFetch.nEndPos); ?k4Hk$V
} dp^PiyL
output.close(); gJr)z7W'8
} x%r$/=
catch(IOException e){e.printStackTrace ();} ]o]`X$n
catch(Exception e){e.printStackTrace ();} lY"l6.c
} w-ald?`
5hy7}*dR
T@.+bD
//读取保存的下载信息（文件指针位置） ;"0bVs`.^e
private void read_nPos() M&V4|D
{ M j[+h|e
try{ ;Us6:}s
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); "lu^
int nCount = input.readInt(); Bo8f52|
nStartPos = new long[nCount]; Z(tJd,
nEndPos = new long[nCount]; 0.wF2!V.
for(int i=0;i<nStartPos.length;i++) D((/fT)eD
{ )s^gT]"N
nStartPos = input.readLong(); -XL?n/M
nEndPos = input.readLong(); =23B9WT
} &odQ&%X
input.close(); BM:p)%Pv#P
} Y\_mqd
catch(IOException e){e.printStackTrace ();} l![79eFp
catch(Exception e){e.printStackTrace ();} F/lL1nTdK
} CHv n8tk
JUA%l
M !"Q7>d
private void processErrorCode(int nErrorCode) mfI[9G
{ ]Xnar:5
System.err.println("Error Code : " + nErrorCode); ;kZD>G8
} 8A]8yX =
0'r}]Mws
Od;k}u6;<
//停止文件下载 @w==*.x
public void siteStop() *(q{k%/M
{ paD[4L?4Hk
bStop = true; fgtwVji
for(int i=0;i<nStartPos.length;i++) !gRU;ZQU_
fileSplitterFetch.splitterStop(); 89D`!`Ah]
3{co.+
=/|GWQj
} =Xr{ Dg
} ,e1c,}
//负责部分文件的抓取 p+b9D
**FileSplitterFetch.java ~I>|f
*/ /_cpSq
package NetFox; 2& Hl wpx
UdkNb}L
p%>!1_'(
import java.io.*; ld(_+<e
import java.net.*; / zNVJhC
:/=P6b;
8q9^
public class FileSplitterFetch extends Thread { w/o8R3F
9m>L\&\_e
`k I}p
String sURL; //File URL ~!TrC<ft
long nStartPos; //File Snippet Start Position %1;Y`>
long nEndPos; //File Snippet End Position 8cY5:plK
int nThreadID; //Thread's ID K[noW
boolean bDownOver = false; //Downing is over K6B6@
boolean bStop = false; //Stop identical Lp$&eROFVs
FileAccessI fileAccessI = null; //File Access interface v8E:64
;MYK TE>m
5ip ZdQ^
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Bt:M^b^
{ rM~Mqpk
this.sURL = sURL; UVi9}zr
this.nStartPos = nStart; +gndW
this.nEndPos = nEnd; C|FI4/-e
nThreadID = id; M-QQ
fileAccessI = new FileAccessI(sName,nStartPos);//定位 j/uMSE
} epk C'
8[^b8^
o%]b\Vl6
public void run() j yp.2c
{ _%rkN0-(a
while(nStartPos < nEndPos && !bStop) r H9}VA:h
{ tx1TtWo
_pS)bxw
d<\X)-"
try{ +BI%.A`2
URL url = new URL(sURL); 'SG<F,[3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); -t`KCf,0
httpConnection.setRequestProperty("User-Agent","NetFox"); |1OF!(:
String sProperty = "bytes="+nStartPos+"-"; PR7bu%Y*eD
httpConnection.setRequestProperty("RANGE",sProperty); p'/%"
Utility.log(sProperty); t2.]v><
bsc b
aFrZ ;_
InputStream input = httpConnection.getInputStream(); 0_>1CW+X
//logResponseHead(httpConnection); pDr/8HEh
kbz+6LcV
2U+wiE|
byte[] b = new byte[1024]; ,5*<C'9
int nRead; R<h:>.M
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) +@Kq
{ jw2hB[WR
nStartPos += fileAccessI.write(b,0,nRead); >]\oVG
//if(nThreadID == 1) QE;,mC>
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Tt0]G_
} g ?%]()E
EJ:2]!O
m:;`mBOc3
Utility.log("Thread " + nThreadID + " is over!"); k lr1"q7
bDownOver = true; ^?0WE
//nPos = fileAccessI.write (b,0,nRead); , YE+k`:
} ^jo*e,y:
catch(Exception e){e.printStackTrace ();} BXl Y V"
} 3XjY
} <m`Os2#
ap|V}jC
c_ 1.
//打印回应的头信息 ;x{J45^
public void logResponseHead(HttpURLConnection con) )hA)`hL F
{ uhmSp+%
for(int i=1;;i++) Dm;aTe
{ 8`b_,(\N
String header=con.getHeaderFieldKey(i); @q" #.?>s
if(header!=null) L|2WTyMU
//responseHeaders.put(header,httpConnection.getHeaderField(header)); >Cr'dKZ}
Utility.log(header+" : "+con.getHeaderField(header)); ve/|"RB
else Z=s]@r
break; h7\16j
} zv\T;_
} kvt"7;(
XlxB%
QfU{W@!h
public void splitterStop() Kv\uBMJNW
{ P<xCg
bStop = true; Wf$P+i*
} ,n{|d33
+-:G+9L@
-v WXL
} TbR Ee;1
1,G f;mcQ
FVHR
/* 6$$ku
**FileAccess.java :"oUnBY%
*//文件访问(定位，写) /{X2:g{
package NetFox; ~c GH+M@
import java.io.*; f+dj6!g5/
+@C|u'
L)Ru]X`
public class FileAccessI implements Serializable{ Nj4^G ~_
PHn3f;I
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 o{ \r1<D
RandomAccessFile oSavedFile; KA0_uty/T
long nPos; uQg&A`4
cLnvb!g'#
}%eXGdC
public FileAccessI() throws IOException ww{07g
{ iX'#~eK*<
this("",0); :.EVvuXI
} ZzO.s$
\>XkK<ye
6~6*(s|]A
public FileAccessI(String sName,long nPos) throws IOException 6Yx/m
{ {f)"F;]V
oSavedFile = new RandomAccessFile(sName,"rw"); j%s:d(H`
this.nPos = nPos; Kkds^v6
oSavedFile.seek(nPos); rv97Wm+
} {5gh.
-r"h[UV)
iYxpIqWw
public synchronized int write(byte[] b,int nStart,int nLen) 5PCKBevV
{ +q3E>K9a
int n = -1; _"%-=^_
try{ `~3y[j]kO
oSavedFile.write(b,nStart,nLen); rwou[QU
n = nLen; sv?Lk4_
} js\|xfDxP
catch(IOException e) /F6=iHK(l
{ h/n&&J
e.printStackTrace (); >)PcK
} ;O7<lF\7o
9i+SU|;j
w[wrZ:[
return n; </8F
} J'>i3eLq
VlQaT7Q
n~NOqvT <
} a5xp[TlXn.
`[Xff24(eb
A5> ,e|
/* |cE 69UFB
**SiteInfoBean.java $>fMu
*/ ^h@1tFF
package NetFox; 2oFHP_HVfu
As7Y4w*+
mN:p=.& <
public class SiteInfoBean { RK`C31Ws
mxV0"$'Fm
KoNJ;YiKtN
private String sSiteURL; //Site's URL /Z*XKIU6v/
private String sFilePath; //Saved File's Path g4 |s9RMD
private String sFileName; //Saved File's Name JH;\wfrD
private int nSplitter; //Count of Splited Downloading File 6-<>P E2
36U zfBa
?R}a,k
public SiteInfoBean() gjVKk
{//nSplitter的缺省值为5 )N4_SA
//default value of nSplitter is 5 #\]:lr{>?4
this("","","",5); }XiV$[xHd
} .UuCTH;6`
4>&%N\$*
^l4=/=RR
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) .:b|imgiv
{ -C|1O%.
sSiteURL= sURL; >f$>Odqe
sFilePath = sPath; yJ&`@gB
sFileName = sName; 4j'cXxo
this.nSplitter = nSpiltter; $*`=sV!r
BM&.Tw|x
@;we4G5
} Sp=6%3fZ]m
[l2ds:
*3A[C-1~.
public String getSSiteURL() ?p8(Uc#73
{ 67/&.d!
return sSiteURL; OA_Bz"
} 5:ZM-kZT
']hB_4v
Wb/q&o
public void setSSiteURL(String value) Ty21-0F
{ X;I;CZ={
sSiteURL = value; sacaL4[_<
} jz%%r Q(
i0%S6vmaS
7aJLC!
public String getSFilePath() ^$7Lmd.qI
{ p<2A4="&
return sFilePath; Lii,L}
} \lnpsf
Ls#=R
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public void setSFilePath(String value) ESl-k2
{ u2SnL$A7
sFilePath = value; |[tlR`A$
} (CRY$+d
S(c,Sinc
e[HP]$\
public String getSFileName() Tkhu,
{ Su0[f/4m.Q
return sFileName; $\|$ekil4
} p1 9j
F(-Q]xj,
I&oHVFY+
public void setSFileName(String value) 9nFPGIz+
{ a3wTcp "r
sFileName = value; ^gwVh~j
} ]}_@!F)
J?WT
Z^w}: {
public int getNSplitter() 5h9`lS2
{ AS34yM(h
return nSplitter; `,mE '3&
} I-E}D"F;p[
{CM%QMM
I@l'Fx
public void setNSplitter(int nCount) $q]:m+Fm
{ ?- 5{XrNm
nSplitter = nCount; T>l=0a #
} W2VH?-Gw
} -vcHSwGb
dF2 &{D"J
ef\Pu\'U
/* -0 [^w
**Utility.java ]>NP?S )R
*/ \dAh^BK1(
package NetFox; )&"l3*x
K<O1PrC
:"9 :J
public class Utility { HL;y5o?
S{7*uK3$
]VifDFL}
public Utility() }|rnyYA
{ hKq#i8py
NGD?.^ (G
B{wx"mK
} Iz/o|o]#
8}3dwr;-
//线程睡眠 c7mIwMhl~
public static void sleep(int nSecond) X'4g\)*
{ / c1=`OJ
try{ Fi+v:L|
Thread.sleep(nSecond); bq/*99``
} =@U~sl[
catch(Exception e) b{|Ha3;w
{ x | =
e.printStackTrace (); NPws^
} -hav/7g
} Y_3{\g|x
uFDJRQJ<
//日志 %oasIiO
public static void log(String sMsg) 'u }|~u?m
{ ;iJ*.wVq
System.err.println(sMsg); 5CZii=@
} e"u=4nk
wu5]S)?*
Pa%;[hbn
public static void log(int sMsg) 9NTBdo%u
{ UD|Qa
System.err.println(sMsg); q-%;~LF
} -~O7.E(ok
} o}&TFhT
gTE/g'3
kB-%T66\
/* z;6Tp
**TestMethod.java \|\Dc0p}
*/ " (c#H
package NetFox; ~y.{WuUD
(9r\YNK
"oZ-W?IKE
public class TestMethod { 6-U+<[,x
\F;V69'
$Hcp.J[O
public TestMethod() 8W$uw~|dw
{ ///xx/weblogic60b2_win.exe (H/JB\~r
try{ 3n;UXYJ%
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); gs)wQgJ[
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); J0BA@jH5
SiteFileFetch fileFetch = new SiteFileFetch(bean); LAG*H
fileFetch.start(); 7%C6hEP/*W
} Az.(tJ X"
catch(Exception e){e.printStackTrace ();} 5z8CUDt 0
n?vw|'(}
}eUeADbC
} \}SA{)
8)IpQG
)N`a4p
public static void main(String[] args) uK6`3lCD
{ xc[LbaBG
new TestMethod(); pPt7M'uL"
} %n-:mSus
} ]-d:wEj
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