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)); +B#qu/By
} gNTh% e
for(int i=0;i<nEndPos.length-1;i++) 1f<RyAE?5
{ cu<y8 :U<
nEndPos = nStartPos[i+1]; O5O.><RP
} ikr7DBLt
nEndPos[nEndPos.length-1] = nFileLength; 4X*Q6rW
} Uh*@BmDA
} {f-XyF1`
`6P?G|'
J8J!#j.
//启动子线程 _1P`]+K\D$
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; PzLJ/QER
for(int i=0;i<nStartPos.length;i++) YN/u9[=`
{ lO[E[c G
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), q4)Ey
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), GJvp{U}y9I
nStartPos,nEndPos,i); n_J5zQJ
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Jns/v6
fileSplitterFetch.start(); ]Ym=+lgi
} +ZX.1[O
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Y3<b~!f
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); X CzXS.
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", +|9f%f6vp
nEndPos = " + nFileLength); Y_+ SA|s
// fileSplitterFetch[nPos.length-1].start(); y[7C% Wj
/,X7.t_-
OMvT;Vgg
//等待子线程结束 } #qQ2NCH
//int count = 0; .wD>Gs{sH[
//是否结束while循环 4j^bpfb,
boolean breakWhile = false; e9lOk)`t
%;tJQ%6-.S
w]F!2b!
while(!bStop) /w0w*nH
{ ,aWCiu}
write_nPos(); pD[pTMG@$
Utility.sleep(500); QhsVIta
breakWhile = true; }YRO'Q{
rfc|`*m}0
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for(int i=0;i<nStartPos.length;i++) lQWBCJ8y
{ !O8.#+
if(!fileSplitterFetch.bDownOver) IhfZLE.,
{ cN5"i0xk
breakWhile = false; wh*:\_!0\
break; RbKwO} z$q
} bf(+ldq
} R1Yqz $#
if(breakWhile) I )5<DZB9
break; V,m3-=q
xvB8YW"
q=+wI"[
//count++; .'&V#D0
//if(count>4) %XR<isn
// siteStop(); ~TM>"eBb
} $cu]_gu
+X[8wUm|^
SwX@I6huM
System.err.println("文件下载结束！"); NZP7r;u
} =-5[Hn%
catch(Exception e){e.printStackTrace ();} @i{]4rk lv
} /e(W8aszi
AX K95eS
(7~%B"
//获得文件长度 2eHx"Ha
public long getFileSize() D?mDG|Z
{ _Z$?^gn
int nFileLength = -1; DLXL!-)z
try{ ` .$&T7
URL url = new URL(siteInfoBean.getSSiteURL()); 14-]esSa
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); dWUUxKC
httpConnection.setRequestProperty("User-Agent","NetFox"); >8(jW
'B,KFA<
{"t5\U6cKM
int responseCode=httpConnection.getResponseCode(); \FXp*FbQ
if(responseCode>=400) 8O9Gs
{ J)Ol"LXV
processErrorCode(responseCode); >uHb ^
return -2; //-2 represent access is error (-J<Vy]
} R+uw/LG
gs>A=A(VYf
w&5/Zh[~~L
String sHeader; ntZ~m
]w-.|vx
Sz)b7:
for(int i=1;;i++) jqtVpNwM
{ _JA:.V^3gm
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); !=y Q)l2
//Utility.log(in.readLine()); bJ6p,]g
sHeader=httpConnection.getHeaderFieldKey(i); ol}`Wwy
if(sHeader!=null) .6Fsw
{ fM2^MUp[=1
if(sHeader.equals("Content-Length")) TRy^hr8~
{ Fpf><Rn
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 6+e4<sy[E
break; {Zl4C;c
} h7*O.Opm=
} +99Bi2H}o
else QtlT&|$
break; *uU4^E(
} }1@E"6kF
} ^cn@?k((A
catch(IOException e){e.printStackTrace ();} #a'r_K=ch)
catch(Exception e){e.printStackTrace ();} @ZG>mP1Vo
6KO(j/Gwp
mV;3ILO
Utility.log(nFileLength); N|<bVq%
[<S^c[47U
| k}e&Q_/G
return nFileLength; t}~UYG(h~
} #Cx%OIi[f
_r5wF(Y?7
7>mhK7l
//保存下载信息（文件指针位置） B\0t&dai|'
private void write_nPos() Eu4 &-i
{ zi.mq&,]R
try{ ^RDU p5,T
output = new DataOutputStream(new FileOutputStream(tmpFile)); _D JCsK|
output.writeInt(nStartPos.length); $Elkhe]O %
for(int i=0;i<nStartPos.length;i++) Qt~B#R. V
{ ckWkZ 78\
// output.writeLong(nPos); I^:F)a:
output.writeLong(fileSplitterFetch.nStartPos); bRsc-Fz6
output.writeLong(fileSplitterFetch.nEndPos); ;W~4L+e
} ~ k<SbFp
output.close(); 6klD22b2$
} AK;^9b-}q:
catch(IOException e){e.printStackTrace ();} y]^#$dK(z
catch(Exception e){e.printStackTrace ();} F|*tNJU>
} p&O8qAaO
AIv<f9*.:
QoseS/
//读取保存的下载信息（文件指针位置） rKT)!o'
private void read_nPos() ?Q?598MC
{ #Qsk}Gv
try{ N%*9&FjrL
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); r&Qt_
int nCount = input.readInt(); b!,ja?
nStartPos = new long[nCount]; 0ERsMnU'
nEndPos = new long[nCount]; ;j!UY.i
for(int i=0;i<nStartPos.length;i++) ^vW$XRnt
{ XmlIj8%9[&
nStartPos = input.readLong(); #fj[kq)&S
nEndPos = input.readLong(); @(){/cF
} KC]tY9 FK
input.close(); H0+:XF\M
} 2qXo{C3
catch(IOException e){e.printStackTrace ();} k}s+ca!B
catch(Exception e){e.printStackTrace ();} b}}y=zO|$
} <p/MyqZf
M?R!n$N_
J^h'9iQpi
private void processErrorCode(int nErrorCode) vnZ4(
{ |(&oI(l5K
System.err.println("Error Code : " + nErrorCode); Vmtzig3w[
} bs P6\'\4
ZMJ3NN]F
ydup)[n
//停止文件下载 J?,?fqb
public void siteStop() 2+Zti8
{ UO1$UF! QC
bStop = true; Z)5klg$c
for(int i=0;i<nStartPos.length;i++) .jaZ|nN8`
fileSplitterFetch.splitterStop(); >3!DOv
-O%[!&`
q}sK
} cyBW0wV1
} g<\>; }e
//负责部分文件的抓取 w?S8@|MK
**FileSplitterFetch.java |@ *3^'
*/ #'8)u)!
package NetFox; 6i-*N[!U
)WmZP3$^TX
F3 Y<ZbxT
import java.io.*; 9?(x>P
import java.net.*; Az9J\V~"
8F)=n \
NA\x<
public class FileSplitterFetch extends Thread { +[_gyLN<5b
Q K j1yG0i
{Hr>X
String sURL; //File URL U&X.
long nStartPos; //File Snippet Start Position ) G|"jFP
long nEndPos; //File Snippet End Position {zu/tCq?
int nThreadID; //Thread's ID ,O2q+'&
boolean bDownOver = false; //Downing is over PF`:1;PU
boolean bStop = false; //Stop identical m|mG;8}pI
FileAccessI fileAccessI = null; //File Access interface O/$ v69:
Hva{A #
a}w&dE$!-
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException pJn>oGeJ&
{ 'f8 p7_F
this.sURL = sURL; kR_E6Fl
this.nStartPos = nStart; .01TTK*
this.nEndPos = nEnd; .T{U^0 )
nThreadID = id; >pnz_MQ
fileAccessI = new FileAccessI(sName,nStartPos);//定位 :/~_sJt C
} XtR`?
eWw y28t
}FZp840
public void run() g&P9UW>qS
{ TtZrttCE6
while(nStartPos < nEndPos && !bStop) `!_?uT
{ N4s$.`
[:BW+6
+yvBSpY
try{ 0$!.c~
URL url = new URL(sURL); sv@}x[L
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); #|q;t
httpConnection.setRequestProperty("User-Agent","NetFox"); ,rXW`7!2
String sProperty = "bytes="+nStartPos+"-"; bu;vpNa
httpConnection.setRequestProperty("RANGE",sProperty); u$\Tg3du2
Utility.log(sProperty); ~O8]3+U
y^3,X_0
|]I#CdO
InputStream input = httpConnection.getInputStream(); ,d5ia4\K
//logResponseHead(httpConnection); {8_:4`YZ
S~}$Ly@
fq{I$syY
byte[] b = new byte[1024]; {<"[D([
int nRead; Mg&HRE
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) }WoX9M; 1
{ UX?X]ZYVR
nStartPos += fileAccessI.write(b,0,nRead); "1AjCHZ
//if(nThreadID == 1) :3:)E
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); =\*S'Ded
} ayHn_
*SWv*sD
WI%zr2T
Utility.log("Thread " + nThreadID + " is over!"); eUYG96Jw
bDownOver = true; 4U:DJ_GN
//nPos = fileAccessI.write (b,0,nRead); h@EJTAi
} <x^IwS
catch(Exception e){e.printStackTrace ();} p{w}
} N{|[R
} g\E ._ab<
f.sPE8#3=
0GF%~6
//打印回应的头信息 s8C:QC
public void logResponseHead(HttpURLConnection con) UX03"gX
{ *pmoLiuB>
for(int i=1;;i++) nsy!p5o
{ CdE2w?1
String header=con.getHeaderFieldKey(i); nvw NjN
if(header!=null) yZQ1] '^31
//responseHeaders.put(header,httpConnection.getHeaderField(header)); u)wu=z8
Utility.log(header+" : "+con.getHeaderField(header)); jD$;q7fB
else |P^ikx6f5
break; zaQ$ Ht
} 3~#ZE;>#
} 6="M0%
5B_-nYJDt
-(`K7T>D.
public void splitterStop() :+kg4v&r
{ MAl{66
bStop = true; 3ZLr"O1l)
} DX7Ou%P,mg
8s\8`2=
x A@|I#
} =lw4 H_
yN%3w0v
] `b<"
/* [J(@$Qix
**FileAccess.java o%y+Y;|?J
*//文件访问(定位，写) sqgD?:@J
package NetFox; RI7qsm6RN
import java.io.*; :5q^\xmmq
rerUM*0
wR`w@5,d
public class FileAccessI implements Serializable{ ZP]2/;h
77Q4gw~2U
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 .N'%hh
RandomAccessFile oSavedFile; 5M/%%Ox
long nPos; x0N-[//YV
TPV6$a<
11^ {WF
public FileAccessI() throws IOException {m1t~ S
{ E` :ZH
this("",0); ^Y1AeJ$L
} eUGmns
HY@kw>I
8,Q.t7v
public FileAccessI(String sName,long nPos) throws IOException \rB/83[;u
{ U)IsTk~}O
oSavedFile = new RandomAccessFile(sName,"rw"); 7zz(#
this.nPos = nPos; mH7CgI
oSavedFile.seek(nPos); (@N~ j&
} f z/?=
MZ >0K
g~i''lng
public synchronized int write(byte[] b,int nStart,int nLen) ?(|TP^
{ fD]An<
int n = -1; ]DL> .<]d
try{ ,Jw\3T1V
oSavedFile.write(b,nStart,nLen); .~V".tZV[
n = nLen; x0TnS#
} *IjdN,wox
catch(IOException e) ^Y*`D_-G
{ f6(9wz$Trt
e.printStackTrace (); O4'kS @
} ?[*@T2Ck
m,kvEQ3
|yId6v
return n; * 7zN
} 8Pnqmjjj
tOlzOBzR
9phD5b~j
} <7sF<KD
|{}d5Z"5;}
?$`1%Y9
/* KqG$zC^N
**SiteInfoBean.java ` i^`Q
*/ ?()E5 4y
package NetFox; ]ZU:%Qhu
KY(l<pm
[W8iM7D
public class SiteInfoBean { |n-a\
7!` C TE
D{Jc+Q$
private String sSiteURL; //Site's URL t"!8
private String sFilePath; //Saved File's Path 3qV>TE]6,
private String sFileName; //Saved File's Name [4+a 1/^
private int nSplitter; //Count of Splited Downloading File xYzcV%-Pm
t0AqGrn
$HR(|{piZ
public SiteInfoBean() (0+GLI8
{//nSplitter的缺省值为5 OA8b_k~
//default value of nSplitter is 5 F~uA-g
this("","","",5); %l]rQjV-
} `)gkkZ$)j
W0r5D9k
n<"a+TTU
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) !A ydhe
{ 5e~{7{
sSiteURL= sURL; #/ gme
sFilePath = sPath; )4o=t.O\K
sFileName = sName; ,:Rq
this.nSplitter = nSpiltter; V }r_
@Tm0T7C
0I ND9h.%
} Z:o' +oh
v'2OHb#
Kw5+4R(5
public String getSSiteURL() bju,p"J1-E
{ #VMBn}
return sSiteURL; N%M>,wT
} lG^mW\O
.tHv4.ob
-fZShOBY`
public void setSSiteURL(String value) OHa{!SaL
{ " :nVigw&
sSiteURL = value; ;r@R (Squ
} bUg2Bm!y
+Muia5G
y[7xK}`_
public String getSFilePath() jJ{ w -$
{ =w>>7u$4
return sFilePath; 4@V<Suw
} B#V4
m#}{"d&J
GT`<jzAiQ
public void setSFilePath(String value) 0T{Y_IG
{ 9[]"%6
sFilePath = value; gQzJ2LU(
} 0_xcrM
bU +eJU_%
~4 xBa:*z
public String getSFileName() (k HQKQmq
{ YI(OrR;V
return sFileName; H fmMf^c
} BrH`:Dw
kpMM%"=V
}mS0{rxD4
public void setSFileName(String value) 1X:whS5S
{ ]e3}9.
sFileName = value; uC8T!z
} 0Ukl#6
(j8,n<o
Q9'p3"yoE
public int getNSplitter() D@vvy6>~s
{ a_fW{;}[
return nSplitter; LyPBFo[?
} ?Dp^dR
|h~/Zz=
RlPByG5K
public void setNSplitter(int nCount) k^%ec3l
{ 0 Ln5e.&
nSplitter = nCount; IF?B`TmZ
} N %/DN
} V$F.`O!hfi
*gpD4c7A\
,ce^"yG
/* MldL"*HW:
**Utility.java \iE9&3Ie
*/ tS\NO@E_Jh
package NetFox; xr-`i
_CwQ}n*
%+W >+xRb
public class Utility { 1kw4'#J8
%IXW|mi
%L|bF"K5;
public Utility() WMl^XZO
{ /Gv$1t^a
HnY"6gTNK
^3s&90
} `Q^Sm`R
B]}V$*$\?
//线程睡眠 M4PUJZ]
public static void sleep(int nSecond) iBW6<2@oZF
{ RvZ-w$E&?
try{ T[=cKYp8\
Thread.sleep(nSecond); Qi]Z)v{^
} cTx/Y&\9
catch(Exception e) 6 &Aa b56
{ o[W3/
e.printStackTrace (); X35U!1Y\
} 29DWRJU
} ;+KgujfU
]@}BdMlHp
//日志 )P+GklI{4
public static void log(String sMsg) 3NZFW{u
{ wupD
System.err.println(sMsg); 2 3w{h d
} \ OINzfbr
Afl'-
17 iq
public static void log(int sMsg) JJ3JULL2
{ MFsy`aiS
System.err.println(sMsg); A+E@OOw*~
} Hu2g (!
} .TS=[WGMS
yzl\{I&
n k3lC/f
/* 8J U~Q
**TestMethod.java ''07Km@x
*/ GlD'?Mk1
package NetFox; vs5wxTM
L umD.3<
?Gw89r
public class TestMethod { <&Xq`i/(
R*C+Yk)Tkt
DA@hf
public TestMethod() / {~h?P}
{ ///xx/weblogic60b2_win.exe lc#zS_
try{ P;/wb/
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); %-|q3 ^s
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); K8c#/o
SiteFileFetch fileFetch = new SiteFileFetch(bean); ,X6j$YLWp
fileFetch.start(); L4Y3\4xXO
} _\;#a
catch(Exception e){e.printStackTrace ();} ?tQv|x
rL"k-5>fd
Xe+FMbBco
} @23x;x
=6YO!B>7
3mz>Y*^?0
public static void main(String[] args) Yk&{VXU<
{ HNT8~s.2
new TestMethod(); Y\\nJuJo
} RyD$4jk+T"
} H2cc).8"
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