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)); E} Uy-
} }/(fe`7:
for(int i=0;i<nEndPos.length-1;i++) ?*4&Z.~J
{ YqR MVWcnk
nEndPos = nStartPos[i+1]; }3lM+]pf
} m{_\@'q
nEndPos[nEndPos.length-1] = nFileLength; vay_QxB5
} V{{b^y
} sUfH1w)0
( y2%G=.j
`"zX<
//启动子线程 eO(VSjo'`
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; @5acTYQ
for(int i=0;i<nStartPos.length;i++) 9!_`HE+(XJ
{ sA3 4`ZAa
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), '"~|L>F%G
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), hP`3Ao
nStartPos,nEndPos,i); 7I^(vQ
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); t \DS}3pv
fileSplitterFetch.start(); V2i*PK X
} lsY5QE:Qrp
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), s#)fnNQ,
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); @]Iku6d-
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", UR1U; k
nEndPos = " + nFileLength); 7AV!v`
// fileSplitterFetch[nPos.length-1].start(); u{ JAC!
ud'r?QDM
f/*Xw{s#
//等待子线程结束 _D$|lk-
//int count = 0; Ga.a"\F.V
//是否结束while循环 }4#%0x`w
boolean breakWhile = false; d=xU f`^
O6Xu/X]
4}W*,&_
while(!bStop) #&1mc_`/
{ ,D+pGxbr
write_nPos(); g>/,},jv[x
Utility.sleep(500); /XS}<!)%
breakWhile = true; P3on4c
'r(}7>~fC
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for(int i=0;i<nStartPos.length;i++) !RFlv
{ ,K+K`"Oy
if(!fileSplitterFetch.bDownOver) (/v(.t
{ 9{'GrL
breakWhile = false; Jq<&`6hn
break; Ad9'q!_en
} J6n@|L!yO
} (](:0H
if(breakWhile) ,m8l /wG
break; xs.>+(@|;
Br`Xw^S
&h`s:Y
//count++; [Sg1\UTl
//if(count>4) i0v;mc
// siteStop(); X4Q?]{
} ] 8+!
2?z3s|+[
L'H'E,
System.err.println("文件下载结束！"); 52C>f6w
} `rbTB3?
catch(Exception e){e.printStackTrace ();} 7xO =:*
} P"XF|*^U
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kHo0I8
//获得文件长度 (Z,v)TOXjV
public long getFileSize() PUuxKW}
{ =Qsh3b&<P
int nFileLength = -1; vfK^^S
try{ g"`BNI]Qp
URL url = new URL(siteInfoBean.getSSiteURL()); $!G7u<`na
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); i`z1if6O
httpConnection.setRequestProperty("User-Agent","NetFox"); ?y>P
vYKKv%LE
Urm&4&y
int responseCode=httpConnection.getResponseCode(); [v^T]L
if(responseCode>=400) CJz2.yd
{ =!GUQLS{
processErrorCode(responseCode); K;k_MA310
return -2; //-2 represent access is error /$|C s
} 4;<?ec(dc
W.r0W2))(
Oq7M1|{
String sHeader; "4<RMYQ
Qo4]_,kR
po4seW!
for(int i=1;;i++) Yev] Lp
{ ~4"adOv
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); P%8 Gaa=
//Utility.log(in.readLine()); sG=D(n1
sHeader=httpConnection.getHeaderFieldKey(i); ?w#V<3=
if(sHeader!=null) ^vn8s~#
{ yS[:C 2v
if(sHeader.equals("Content-Length")) 0BMKwZg
{ sX.L
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); @i'RIL}
break; Q})x4
} ^ |z|kc
} TD'RvTpl
else , ;W6wj
break; q6bi{L@/R
} f=+|e"i#p
} r{!]` '8
catch(IOException e){e.printStackTrace ();} 3k.{gAZKh
catch(Exception e){e.printStackTrace ();} nsKl3}uU
[<\k
~Z9Eb|B
Utility.log(nFileLength); lr'h
!8lG"l|,l
cfBq/2I
return nFileLength; AyKvh
} 0"ksNnxK
;R|i@[(J
J3fk3d`2
//保存下载信息（文件指针位置） = NHuj.
private void write_nPos() /{>$E>N;
{ cKJf0S:cx-
try{ cXU8}>qY7
output = new DataOutputStream(new FileOutputStream(tmpFile)); w#vSZbh
output.writeInt(nStartPos.length); Zyt,D|eWj
for(int i=0;i<nStartPos.length;i++) 7I;xRo|
{ NRN3*YGo
// output.writeLong(nPos); 9 js!gJC
output.writeLong(fileSplitterFetch.nStartPos); x' >Nz{B,P
output.writeLong(fileSplitterFetch.nEndPos); o=}}hE\H
} BgRfy2:
output.close(); $&&mGD;?K
} dn(I$K8
catch(IOException e){e.printStackTrace ();} [EI~/#;
catch(Exception e){e.printStackTrace ();} 0zQ"5e?qy
} U_i%@{
K&Ner(/X`6
Rah"La
//读取保存的下载信息（文件指针位置） Cuu yG8
private void read_nPos() d` %8qLIW
{ ^0)Mc"&{
try{ r<VZEbm)
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); a~q_2S]h
int nCount = input.readInt(); nGQc;p5;
nStartPos = new long[nCount]; 8,B?!%FP
nEndPos = new long[nCount]; %IrR+f+H
for(int i=0;i<nStartPos.length;i++) +`tl<rg;
{ 4<}!+X7m
nStartPos = input.readLong(); > %h7)}U
nEndPos = input.readLong(); % `Q[?(z
} c%y(Z5
input.close(); z"#iG&>a,
} 2-!OflkoM0
catch(IOException e){e.printStackTrace ();} Z/-9G
catch(Exception e){e.printStackTrace ();} EQ 'L"
} )4:K@
Loz5[L
gZA[Sq
private void processErrorCode(int nErrorCode) I|zak](HU
{ HYcLXhvgu
System.err.println("Error Code : " + nErrorCode); G>Fk )
} \WS2g"(
}L mhM
!dnCrR
//停止文件下载 g)0>J
public void siteStop() ~o{GQ>
{ eS#kDa/ %
bStop = true; 5Ku=Xzvq
for(int i=0;i<nStartPos.length;i++) & -r^Q
fileSplitterFetch.splitterStop(); krqz;q-p~
S!+c1q: ].
r-^FM~Jp
} ?,s]5
} yP$@~L[!
//负责部分文件的抓取 ~8 >Tb
**FileSplitterFetch.java :j(e+A1@
*/ R[_Q}W'HG
package NetFox; (~>uFH
=MR.*m{
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import java.io.*; jr/
import java.net.*; #(@!:f1
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y;Ez|MS
public class FileSplitterFetch extends Thread { @*?)S{8
/my5s\;s|z
')R+Z/hG.
String sURL; //File URL w8=&rzr8
long nStartPos; //File Snippet Start Position Vn&{yCm3
long nEndPos; //File Snippet End Position cp1-eR_&
int nThreadID; //Thread's ID /80H.|8O
boolean bDownOver = false; //Downing is over u<L<o2
boolean bStop = false; //Stop identical [U5@m]>^
FileAccessI fileAccessI = null; //File Access interface 4X-"yQ<U
CdBpz/
bG0 |+k3O
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 87!D@Xn
{ ;X_bDiG$
this.sURL = sURL; I+oe{#:.
this.nStartPos = nStart; [8C|v61Y
this.nEndPos = nEnd; vHJOpQmt~
nThreadID = id; IRhi1{K$"
fileAccessI = new FileAccessI(sName,nStartPos);//定位 * 'eE[/K
} &}'FC7}
$>JfLSyC
5)5$h]Nz>
public void run() uzoI*aqk-s
{ Pj-.oS2dA
while(nStartPos < nEndPos && !bStop) *wk?{ U
{ D\:dn
^VC/tJ
# &,W x
try{ 1NAGGr00
URL url = new URL(sURL); Fqt,VED
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); jJY{np
httpConnection.setRequestProperty("User-Agent","NetFox"); l4s*+H$vd?
String sProperty = "bytes="+nStartPos+"-"; jKh:}yl4
httpConnection.setRequestProperty("RANGE",sProperty); }_/]f!]
Utility.log(sProperty); xzi_u.iOP
nxWm
@4t_cxmD
InputStream input = httpConnection.getInputStream(); =K)[3mXX
//logResponseHead(httpConnection); {EfA#{x
QdIx@[+WOq
_sb~eB~<(
byte[] b = new byte[1024]; i:a*6b.U@N
int nRead; zif&;)wV/
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) c"O4=[N: ;
{ Y#,&Tu
nStartPos += fileAccessI.write(b,0,nRead); @m5c<(bkfp
//if(nThreadID == 1) T,a71"c
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); '[Sm w'n6-
} |}7!'f\M
]'NL-8x">
nt&"? /s
Utility.log("Thread " + nThreadID + " is over!"); 1[yy/v'q
bDownOver = true; YdZ9##IU3
//nPos = fileAccessI.write (b,0,nRead); hW!2C6
} z''ejq
catch(Exception e){e.printStackTrace ();} rp '^]Zx
} C669:%
} HNRAtRvnY
|.4>#<$__
A"B#t"
//打印回应的头信息 l4gF.-.GYF
public void logResponseHead(HttpURLConnection con) 4#Xz-5v
{ 7|HIl=
for(int i=1;;i++) YQ$LU\:
{ )3 I~6ar
String header=con.getHeaderFieldKey(i); O#<F"e;$
if(header!=null) 3'Hz,qP
//responseHeaders.put(header,httpConnection.getHeaderField(header)); J9*i`8kU.
Utility.log(header+" : "+con.getHeaderField(header)); ZEp>~dn;
else zfD@/kU
break; &cWC&Ws"
} v<Ywfb
} Jc7}z:UB
?8do4gT+1
/1v:eoF;
public void splitterStop() P BVF'~f@j
{ vM@8&,;
bStop = true; f\rE{%
} ;reBJk
J-|&[-Z
4@+']vN4
} }S$OE))u
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#bJp)&LO
/* cL<,]%SkE
**FileAccess.java X }`o9]y
*//文件访问(定位，写) xnC:?d
package NetFox; B"sB0NuT/$
import java.io.*; Pl. y9g~
.kU}x3m
l^XOW- ;u
public class FileAccessI implements Serializable{ cyLl,OA
Bq;GO
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 27+~!R~Yw
RandomAccessFile oSavedFile; P5H_iH
long nPos; ymp ik.'
.l hS
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public FileAccessI() throws IOException }= wor~
{ =:Yrb2gP_\
this("",0); VP~(;H5%
} K_AdMXF9
UlWm). b;v
o[1#)&
public FileAccessI(String sName,long nPos) throws IOException `M*jrkM]x
{ op@=0d??
oSavedFile = new RandomAccessFile(sName,"rw"); Dpwqg3,
this.nPos = nPos; #K`0b$
oSavedFile.seek(nPos); fLpWTkr0
} r7sA;Y\
Q_Br{ `c
M KX+'p\w
public synchronized int write(byte[] b,int nStart,int nLen) =W;e9 6#
{ ubZJUm
int n = -1; bEB2q\|Je
try{ ie11syhV"
oSavedFile.write(b,nStart,nLen); @U4hq7xzV2
n = nLen; l[]cUE
} %-]a[qf3
catch(IOException e) uts>4r>+
{ H0!$aO
e.printStackTrace (); 2~4&4
} 5*f54g"'
qcouZO
j/_&]6!
return n; C0K: ffv;<
} fdWqc_
@)x*62r+
,a?oGi
} 3;FV^V'
j74hWz+p4
Q% d1O
/* m[(_fOd
**SiteInfoBean.java kh{3s:RQfC
*/ C=|8C70[%N
package NetFox; {=\Fc`74
?:M4GY"gV
[KFCc_:
public class SiteInfoBean { q2r$j\L%
{NQCe0S+p
Mvue>)g~>
private String sSiteURL; //Site's URL ' tHa5`
private String sFilePath; //Saved File's Path VM:|I~gJ
private String sFileName; //Saved File's Name }JWkV1
private int nSplitter; //Count of Splited Downloading File ^%!SKhRIK
";7xE#jRk
;c)( 'k<
public SiteInfoBean() O) TS$
{//nSplitter的缺省值为5 _si5z
//default value of nSplitter is 5 zd)QCq
this("","","",5); ?G,gPb
} .j&#
jVLJqWP'!
Xz)qtDN|(
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) <5mv8'{L
{ #Q)r6V:
sSiteURL= sURL; |:&O!36
sFilePath = sPath; UlXxG|
sFileName = sName; >d=pl}-kOQ
this.nSplitter = nSpiltter; Ue60Mf
;2\6U;
W8$0y2
} _'ebXrbZB
#AB5}rPEI
oPF]]Imu
public String getSSiteURL() ~,ozhj0f/
{ Rzh.zvxTp
return sSiteURL; kxd*B P
} ;x2o|#`b
oGB|k]6]|
{l5fKVb\C
public void setSSiteURL(String value) <xF]ca
{ $2}#):`
sSiteURL = value; JB].ht
} @{q<"hT
m2"e ]I
[>r0 (x&.
public String getSFilePath() :b(W&iBWhI
{ {:("oK6w
return sFilePath; enZZ+|h
} L'S,=NYXY
UOf\pG
7n.Oem
public void setSFilePath(String value) .gmS1ju
{ +0z7}u\x
sFilePath = value; e3W~6P
} j*gJP !
kE.4 #
TwI s_r:
public String getSFileName() #=S^i[K/
{ ^g|cRI_"
return sFileName; s[y.gR.(
} i>,AnkI&
~gW^9nWYU
d)bsyZ;U
public void setSFileName(String value) A9 g%>
{ k_,& Q?GtU
sFileName = value; Fz,jnV9=j
} xQDQgvwa
HnKgD:
_fu <`|kc
public int getNSplitter() M /v@C*c
{ !rr,(!Ip?O
return nSplitter; dd<l;4(
} z)U7
;h+~xxu=X
[RN]?,
public void setNSplitter(int nCount) 5|*`} ;/y
{ N'9T*&o+
nSplitter = nCount; :&TM0O
} aK -x{
} M @-:iP
u "jV#,,
d[p2?]
/* <>9!oOa
**Utility.java 1u7D:h>#
*/ ?YS>_MN
package NetFox; tx>7?e8E
E5)0YYjHZ
9l&q}
public class Utility { gee~>l
m<-!~ ew
uf#h~;B
public Utility() )]FXUz|;
{ 'xj5R=V
l7qW)<r
w/ rQOHV{
} y42Cg
;J,(YNI 1
//线程睡眠 [UZr|F
public static void sleep(int nSecond) rf%lhBv
{ Rh|9F yN
try{ J|f29B-c
Thread.sleep(nSecond); o>,r<
} >d p/
catch(Exception e) reh{jMC
{ wCNn/%C
e.printStackTrace (); I ]ZZN6"
} *YeQCt-l
} {@)ZXg
4 O8ct,Y
//日志 Oa~ThbX7
public static void log(String sMsg) HS{Vohy>
{ N=<`|I
System.err.println(sMsg); |_TI/i>?'
} px K&aY8
"nu]3zcd
Fb]+h)on
public static void log(int sMsg) !P=Cv=
{ e!jy6t
System.err.println(sMsg); =b:XL#VA
} EwN{|34C
} 8.B'O>\T
}^Q:Q\
Mt-r`W3 q
/* pvyEs|f=%
**TestMethod.java oc( '!c
*/ K$h\<_V
package NetFox; y'!OA+ob
H)D|lt5xy
dE_Xd:>
public class TestMethod { lEFd^@t
H575W"53
_Pqq*
public TestMethod() W^L^7
{ ///xx/weblogic60b2_win.exe OA3J(4!"W
try{ mEd2f^R
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); >z\IO
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); `w:kY9
SiteFileFetch fileFetch = new SiteFileFetch(bean); 9hIKx:XCg
fileFetch.start(); Ldz]FB|
} F*PhV|XU
catch(Exception e){e.printStackTrace ();} -/JEKwc
`-pwP
baII!ks
} hYkkr&
}b(hD|e
Th9V8Rg+E
public static void main(String[] args) W`Gbo uxd
{ Qi`3$<W>
new TestMethod(); [Xu8~c X
} c{/R?<
} eW(pP>@k,
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