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)); *dTI4k
} o7qZy |\4S
for(int i=0;i<nEndPos.length-1;i++) qs["&\@
{ TQor-Cymz
nEndPos = nStartPos[i+1]; '@{'T LMCi
} 2feiD?0
nEndPos[nEndPos.length-1] = nFileLength; Vy-kogVt
} u_;&+o2
} LD.^.4{c:
/2<1/[#
y;.U-}e1
//启动子线程 ,KfBG<3
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; dbmty|d
for(int i=0;i<nStartPos.length;i++) Y&G]M
{ \Q CH.~]
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), I6jDRC0<
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ?3I93Bt7
nStartPos,nEndPos,i); F!LVyY"w
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); -W#-m'Lvu
fileSplitterFetch.start(); shn{]Y
} e=8z,.Xk
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), &fyT}MA
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); K}r@O"6*\
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", |i}5vT78
nEndPos = " + nFileLength); _ ?\4k{ET
// fileSplitterFetch[nPos.length-1].start(); O%>FKU>(?
R*DQm
3U_,4qf
//等待子线程结束 c`F~vrr)X
//int count = 0; 2l8TX#K
//是否结束while循环 3;N+5*-
boolean breakWhile = false; tn"n~;Bh?:
Hq>"rrVhx
T|/B}srm
while(!bStop) O%$XgEJ8p
{ {<p-/|Z52
write_nPos(); zUe)f~4
Utility.sleep(500); 9b8kRz[ c
breakWhile = true; _olhCLIR-
3BTXX0yx
|X'Pa9u
for(int i=0;i<nStartPos.length;i++) Uu<Tn#nb
{ "EE=j$8u+
if(!fileSplitterFetch.bDownOver) wG,"ZN
{ S~Z`?qHWh
breakWhile = false; pE^jUxk6
break; tH}$j
} _:ORu Vk
} 5UTIGla
if(breakWhile) o:.6{+|N
break; P ]prrKZe,
f`[gRcZ-
KBb{Z;%
//count++; %+1;iuDL
//if(count>4) T##_?=22I
// siteStop(); 09r0Rb
} jOE~?{8m
`X=2Ff
5@:c6(5$
System.err.println("文件下载结束！"); bR0z$~
} R3[H#*gF<
catch(Exception e){e.printStackTrace ();} AzfYw'^&9
} /IkSgKJiz\
%.zcE@7*
^<}>]F_
//获得文件长度 A18&9gY
public long getFileSize() PGj?`y4
{ bSKe@4C
int nFileLength = -1; ]xYm@%>6
try{ X-Q;4M-CJ
URL url = new URL(siteInfoBean.getSSiteURL()); /.[;u1z"^
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 1Ar6hA
httpConnection.setRequestProperty("User-Agent","NetFox"); knPo"GQW
:We}l;.jQ
lwhVP$q}
int responseCode=httpConnection.getResponseCode(); Z,? T`[4B
if(responseCode>=400) --32kuF&(
{ f"wm]Q59
processErrorCode(responseCode); OFyZY@B-C~
return -2; //-2 represent access is error 7wm9S4+|
} e@GR[0~
\N?,6;%xB
R24ZjbKL
String sHeader; (ohza<X;6
Za&.sg3RG
us:V\V
for(int i=1;;i++) jW?siQO^
{ L'*P;z7<
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); l$:.bwXXO
//Utility.log(in.readLine()); fuwv,[m
sHeader=httpConnection.getHeaderFieldKey(i); 7n_'2qY
if(sHeader!=null) N@z+h
{ ]Q%|69H}B
if(sHeader.equals("Content-Length")) [T5z}!_y
{ +yh-HYo`
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); E@f2hW2
break; 6*cY[R|q!
} @eQo
} w'Cn3b)`
else 5T,In+~Kd
break; P/'9k0zs)
} -d|VXD5N
} "n4' \ig
catch(IOException e){e.printStackTrace ();} N~w4|q!]
catch(Exception e){e.printStackTrace ();} Fp`MX>F
bc".R]
@`</Z)
Utility.log(nFileLength); F$;vPAxbK"
=>PBdW
* MJl(
return nFileLength; @k~_ w#
} }iK_7g`yKa
pxF<L\L?:
E8:4Z$|c
//保存下载信息（文件指针位置） *@C4~Zo
private void write_nPos() N1O& fMz
{ jv"^_1
try{ V&' :S{i
output = new DataOutputStream(new FileOutputStream(tmpFile)); =Wl*.%1 b
output.writeInt(nStartPos.length); SSS)bv8m
for(int i=0;i<nStartPos.length;i++) Fe4QWB6\U
{ >/kwy2
// output.writeLong(nPos); 7=o2$
output.writeLong(fileSplitterFetch.nStartPos); m^8KHa
output.writeLong(fileSplitterFetch.nEndPos); wR"4slY_%
} 4sVr]p`
output.close(); m-~eCFc
} $S"QyAH~-a
catch(IOException e){e.printStackTrace ();} WF6'mg^^?
catch(Exception e){e.printStackTrace ();} =uYz4IDB
} )BuS'oB
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Y'.WO[dgf
//读取保存的下载信息（文件指针位置） 4E Hb
private void read_nPos() NjTVinz
{ sH^?v0^a
try{ h-XMr_F
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); wGqQR)a
int nCount = input.readInt(); _t:l:x.;T
nStartPos = new long[nCount]; a=55bEn
nEndPos = new long[nCount]; ~~.v*C[
for(int i=0;i<nStartPos.length;i++) U#B,Q6~
{ n&. bs7N2
nStartPos = input.readLong(); T4W"!4[
nEndPos = input.readLong(); jU#/yM"Y
} doCWJ
input.close(); kXj%thDx
} IZm_/
catch(IOException e){e.printStackTrace ();} iwHy!Vi-5
catch(Exception e){e.printStackTrace ();} _HT*>-B
} 0I.9m[<Fc
3X+uJb2
g5EdW=Dt,
private void processErrorCode(int nErrorCode) 0d-w<lg9
{ b}G4eXkuj
System.err.println("Error Code : " + nErrorCode); a<.7q1F
} >.D0McQg
;w(]z
+ *YGsM`E9
//停止文件下载 BO5gwvyI
public void siteStop() %j].' ;
{ QK5y%bTSA
bStop = true; 728}K^7:
for(int i=0;i<nStartPos.length;i++) iA~b[20&
fileSplitterFetch.splitterStop(); imx/hz!
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dVDQ^O&
} 9<An^lLK*
} /`iBv8!
//负责部分文件的抓取 TA47lz q
**FileSplitterFetch.java 7'[C+/:
*/ #]s>
package NetFox; gTK5z.]
8s4y7%,|
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import java.io.*; TQ?D*&
import java.net.*; H=vrF-#
DPfP)J:~
nL}bCX{
public class FileSplitterFetch extends Thread { k'N `5M)
U!F~><
}2Lh'0 xY
String sURL; //File URL )x.}B4z
long nStartPos; //File Snippet Start Position k_9tz}Z
long nEndPos; //File Snippet End Position p[(VhbN
int nThreadID; //Thread's ID Ejdw"P"
boolean bDownOver = false; //Downing is over >G2o
boolean bStop = false; //Stop identical rK*s/mX <
FileAccessI fileAccessI = null; //File Access interface +#5nk,1c>
j+3~
]JX0:'x^
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException s,TKC67.%+
{ 5/Ng!bW
this.sURL = sURL; H/_R!G8\
this.nStartPos = nStart; r}i<cyL
this.nEndPos = nEnd; %$j)?e
nThreadID = id; EXDtVa Ot
fileAccessI = new FileAccessI(sName,nStartPos);//定位 j%iz>
} dbkccO}WB
%3e}YQe)
\?[#>L4
public void run() 5_+vjV;5
{ -OpI,qyS
while(nStartPos < nEndPos && !bStop) 4#uWj?u
{ PsDks3cG
?)#dP8n
M}4%LjD
try{ O6P0Am7s
URL url = new URL(sURL); \5^#5_<
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); /"?y @;Y~
httpConnection.setRequestProperty("User-Agent","NetFox"); omM*h{z$$
String sProperty = "bytes="+nStartPos+"-"; buo_H@@p{s
httpConnection.setRequestProperty("RANGE",sProperty); rt%.IQdY
Utility.log(sProperty); *b?C%a9
?H7*?HV
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InputStream input = httpConnection.getInputStream(); FxSBxz<N-A
//logResponseHead(httpConnection); (Q !4\Gy
<@n/[ +3
Q3#-q>;7
byte[] b = new byte[1024]; @oC8:
int nRead; h0NM5
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ZLdvzH@'
{ ;$@7iL
nStartPos += fileAccessI.write(b,0,nRead); u~yJFIo
//if(nThreadID == 1) |KF X0*70
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 'v4#mf
} m~9Qx`fi`
2q J}5
m~~_iz_*
Utility.log("Thread " + nThreadID + " is over!"); `rC9i5:
bDownOver = true; 1oaiA/bq
//nPos = fileAccessI.write (b,0,nRead); .-+_>br~
} v?rjQ'OP
catch(Exception e){e.printStackTrace ();} gZgb-$b
} )((Jnm D
} 2%N$Y]
nBL7LocvR
~C< X~$y&
//打印回应的头信息 693J?Yah[
public void logResponseHead(HttpURLConnection con) \pZ,gF;y
{ w!)B\l^+c
for(int i=1;;i++) o)'T#uK
{ x^}kG[s
String header=con.getHeaderFieldKey(i); T[s_w-<7$
if(header!=null) bL (g$Yi
//responseHeaders.put(header,httpConnection.getHeaderField(header)); !<]%V]5[_
Utility.log(header+" : "+con.getHeaderField(header)); ys:1%D,,_
else `pzp(\lc
break; e0"R7a
} tfj6#{M5
} i$)bZr\
=,KRZqz
&TE=$a:d&
public void splitterStop() 9 )u*IGj
{ 6 k+FTDL
bStop = true; CJk$o K{Q
} H r?G_L
*. l,_68
O^hWG ~o
} zu<b#Wv
EtJyI&7VK
*7.!"rb8A
/* Gvv~P3Dm
**FileAccess.java i4 KW
*//文件访问(定位，写) 7 2ux3D
package NetFox; VYkOJAEBg
import java.io.*; -_.)~)P
*PE1)bF
Oi&.pY:X-
public class FileAccessI implements Serializable{ !7@IWz(,"
_)Q)tOW
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 ed4:r/Dpo
RandomAccessFile oSavedFile; 8I04Nx
long nPos; >>=lh
}N(-e$88
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public FileAccessI() throws IOException G>&=rmK"
{ ZO{uG(u
this("",0); KZzOs9 s
} jDIO,XuF
|Y"q. n77
5b3Wt7
public FileAccessI(String sName,long nPos) throws IOException <~t38|Ff@
{ H1rge<
oSavedFile = new RandomAccessFile(sName,"rw"); z$oA6qB)
this.nPos = nPos; Z+)R%Z'aL
oSavedFile.seek(nPos); <",4O
} 4m$nVv
,x!P|\w.G{
[sp=nG7i&
public synchronized int write(byte[] b,int nStart,int nLen) Rv ?Go2
{ 2Ch!LS:+
int n = -1; g !w7Yv
try{ LEvdPG$)
oSavedFile.write(b,nStart,nLen); G`PSb<h\oc
n = nLen; mm\Jf
} `o yz"07m
catch(IOException e) NqvL,~1G
{ H7?C>+ay
e.printStackTrace (); 048BQ
} v5i[jM8
!OekN,6
TAlpy$
return n; &K2[>5 mG
} } WY7!Y
PcC9)x
p>h B&h
} 2<)63[YO
Fh9`8
.,(bDXl?
/* e4u$+
**SiteInfoBean.java qCOv4b`
*/ >/nS<y>
package NetFox; VS@o_fUx)
kX."|]
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public class SiteInfoBean { "12.Bi.O"[
@4Z>;
$Ll]h</Z
private String sSiteURL; //Site's URL kc^Q?-?
private String sFilePath; //Saved File's Path ,,S5 8\x
private String sFileName; //Saved File's Name 'W usEME
private int nSplitter; //Count of Splited Downloading File sh[Yu
\Xc6K!HJM
{EGiGwpf
public SiteInfoBean() KG6ki_
{//nSplitter的缺省值为5 &10vdAnBRC
//default value of nSplitter is 5 Ke,UwYG2~G
this("","","",5); 55MsF}p
} 8:0QIkqk
3]WIN_h
=_I2ek
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) `DIIJ<;g
{ ^-cj=on=Q
sSiteURL= sURL; hNmC(saMGm
sFilePath = sPath; A U9Y0<
sFileName = sName; GLQ1rT
this.nSplitter = nSpiltter; JDfkm+}uY
G$XvxJ
~V[pu
} B-ReBtN
)+RTA y[k
1O*5>dkX;%
public String getSSiteURL() $wH{snX
{ b>=MG8
return sSiteURL; ^'!]|^
} "8%B (a 5A
hH[UIe
xK9"t;!C&
public void setSSiteURL(String value) uS<7X7|!0
{ =z'- B~
sSiteURL = value; h2ewYe<87`
} Z0g3> iItM
]N_(M
f1(V~{N,+
public String getSFilePath() 5p}Y6Lc\j
{ DZ5%-
return sFilePath; s$css{(ek
} :TJv<NZi'
<8yzBp4gZ
rlk0t159
public void setSFilePath(String value) no`c[XY
{ ]c]rIOTN
sFilePath = value; asb-syqU
} *,5V;7OR
i`)bn1Xm
35B G&;C
public String getSFileName() @G[P|^B
{ 0b+OB pqN
return sFileName; r/'9@oM
} cP%mkh_ri
Kj,C9
h!ZEZ|{
public void setSFileName(String value) ."Wdpf`~
{ Da*=uW9
sFileName = value; /2pf*\u
} 0"7xCx
e^Q$Tog<
y`wTw/5N
public int getNSplitter() >;kCcfS3ct
{ L ?g|:
return nSplitter; *`OgwMr)M
} $r)+7i
xZW6Hk_
*CZvi0&
public void setNSplitter(int nCount) md:$OC3
{ Y~EKMowI&e
nSplitter = nCount; {i y[8eLg
} 3XdN\xc
} @-nCK Yj
Yh)yp?
S/G6NBnbS
/* 4zs1BiMG
**Utility.java ,}2yxo;i
*/ H$TYp
package NetFox; 0KO_bF#EB=
q+f]E&':
lMz5))Rr
public class Utility { La9v97H:
sc'QNhrW
*t J+!1
public Utility() __r]@hY
{ |&B.YLx
T`KH7y|bv
YYU Di@K
} <jE6ye(R
l[lUmE
//线程睡眠 yPrp:%PS
public static void sleep(int nSecond) UOHU1.3$T
{ rU<NHFGj4
try{ s''?: +
Thread.sleep(nSecond); hNs970i
} D,%R[F?5O
catch(Exception e) g\;AU2?p7
{ 3kFSu
e.printStackTrace (); <6^MVaD
} {WUW.(^]G
} y>wrm:b-O
>FED*C4
//日志 ?#?[6t
public static void log(String sMsg) ks|[`FH
{ BqC, -gC
System.err.println(sMsg); LW6&^S?4{
} =S/$h}Vi
maQE Bi,
>yFEUD:
public static void log(int sMsg) 3"=%[
{ 0jCYOl
System.err.println(sMsg); ^{&Vv(~!Q
} WF\ hXO
} +shT}$cb1
;@p2s'(
OrP-+eg
/* G0Zq:kJ
**TestMethod.java #k2&2W=x
*/ j~,7JJ (y
package NetFox; )R$+dPu>
7uG@hL36
_"n1"%Ns
public class TestMethod { $O"S*)9
$G/h-6+8
"+3p??h%Rq
public TestMethod() z3+y|nx!
{ ///xx/weblogic60b2_win.exe AY4ZU CqI
try{ Q!K@
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); YSwAu,$jf
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); !Cxo4Twg
SiteFileFetch fileFetch = new SiteFileFetch(bean); [^xLK
fileFetch.start(); iTsmUq<b]l
} "3o{@TdU
catch(Exception e){e.printStackTrace ();} cmgI,n-o?
*Wk y#
,9<}V;(
} 2%4dA$H#4w
_[;>V*?zp5
<>$`vuU
public static void main(String[] args) )&:4//}a
{ =H6"\`W
new TestMethod(); p\I,P2on
} %7=B?c|
} ,73kh
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