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)); u(\b1h n
} #8%Lc3n
for(int i=0;i<nEndPos.length-1;i++) 5bH@R@3m
{ Yr,e7da
nEndPos = nStartPos[i+1]; pI( OI>~3
} UKZsq5Q
nEndPos[nEndPos.length-1] = nFileLength; G;yf]xFd
} }Rt?p8p
} 4@4$kro
3!Gnc0%c
hof:36 <
//启动子线程 \6T&gX
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; k129)79
for(int i=0;i<nStartPos.length;i++) TF^Rh4
{ $eCxpb..
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), |/Ggsfmby
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 8)\ ?6C
nStartPos,nEndPos,i); 0AZ Vc
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Pn[-{nz
fileSplitterFetch.start(); }~:`9PV)Z%
} [as\>@o
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Z0`Bn5
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); dli?/U@hO
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", N41)?-7F
nEndPos = " + nFileLength); i ?%;s5<
// fileSplitterFetch[nPos.length-1].start(); f0~<qT?:n
;*BG{rkr
,gVA^]eDh
//等待子线程结束 5*/~) wN\U
//int count = 0; 2TXrVaM
//是否结束while循环 %|*tL7
boolean breakWhile = false; +g(>]!swb
l:-$ulAx
2`9e20
while(!bStop) AU -,
{ V`fp%7W
write_nPos(); v,I4ozDx
Utility.sleep(500); _ho9}7 >
breakWhile = true; $nUhM|It
-y|>#`T/
4@AY~"dq
for(int i=0;i<nStartPos.length;i++) <wfPbzs-V
{ <~@}r\
if(!fileSplitterFetch.bDownOver) 2Nrb}LH
{ 1xP*
breakWhile = false; 3q:U0&F
break; !'8.qs
} (HbA?Aja
} 9AF%Y:y
if(breakWhile) S~()A*5
break; wXZ"}uT<}
uH="l.u
F$.h+v
//count++; ?l/VCEZP
//if(count>4) lHerEv<ja
// siteStop(); $ @g\wz
} He vZ}.
a> qB k})
(yA`h@@WS
System.err.println("文件下载结束！"); v7gs $'Q
} /*Iq,"kGz
catch(Exception e){e.printStackTrace ();} c|RTP
} $ha,DlN
vX1 8 ]
>!sxX = <
//获得文件长度 h*d1G9%Q1
public long getFileSize() ~ES6Qw`Oe
{ ywQ[>itMa
int nFileLength = -1; S9RH&/^H
try{ GB,f'Afl
URL url = new URL(siteInfoBean.getSSiteURL()); ~+|Vzm|S}
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); O/Cwm;&t
httpConnection.setRequestProperty("User-Agent","NetFox"); |`eHUtjH
o]/*YaB2>
>n$V1U&/
int responseCode=httpConnection.getResponseCode(); ^x2zMB\t
if(responseCode>=400) NH9"89]E
{ " b3-'/&
processErrorCode(responseCode); WN#S%G:Q)
return -2; //-2 represent access is error $0 ]xeD0X
} 8uAA6h+
.JCd:'-
L7\V^f%yCm
String sHeader; FxU a5n
Fi)(~ji:
+a3H1 tt~
for(int i=1;;i++) jKr\mb
{ rf?%- X(V
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); T,@s.v
//Utility.log(in.readLine()); *I]/ [d
sHeader=httpConnection.getHeaderFieldKey(i); Xna58KF/
if(sHeader!=null) g$f+X~Q
{ ['m7Wry
if(sHeader.equals("Content-Length")) sU Er?TZ
{ =$mPReA3v
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); \MqOHM.[
break; Jlp nR#@
} g'cLc5\
} %\"<lyD
else UahsX
break; lT^/8Z<g
} -.xiq0
} H46N!{<;@
catch(IOException e){e.printStackTrace ();} 6 &Lr/J76
catch(Exception e){e.printStackTrace ();} Ef @
hXnfZx%
A(eB\qG
Utility.log(nFileLength); *'w?j)}A9g
Zzn N"Si,
~Y/:]&wF
return nFileLength; |PtfG2Ty?
} .jUM'; l
3c%_RI.
bog3=Ig-
//保存下载信息（文件指针位置） }#r awVe=
private void write_nPos() @yM$Et5
{ w**~k]In
try{ p0rmcP1Ln
output = new DataOutputStream(new FileOutputStream(tmpFile)); "7q!u,u
output.writeInt(nStartPos.length); +pPfvE`
for(int i=0;i<nStartPos.length;i++) \VpN:RI
{ {8I,uQO
// output.writeLong(nPos); iD*21c<kd
output.writeLong(fileSplitterFetch.nStartPos); xv"v='
output.writeLong(fileSplitterFetch.nEndPos); 5Q;Q
} fUMjLA|*I<
output.close(); f$76p!pDa
} v%rmfIU
catch(IOException e){e.printStackTrace ();} |'Z+`HI
catch(Exception e){e.printStackTrace ();} qv^P
} e%s1D
AL!ppi
"1$X5?%
//读取保存的下载信息（文件指针位置） 0qINa:Ori
private void read_nPos() EXMW,
{ >?O?U=:<
try{ IClw3^\l
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); !YPwql(
int nCount = input.readInt(); 7Kf
nStartPos = new long[nCount]; jW]"Um-]
nEndPos = new long[nCount]; >AFQm
for(int i=0;i<nStartPos.length;i++) <Drm#2x!E
{ I cASzSjYX
nStartPos = input.readLong(); m%0_fNSJ
nEndPos = input.readLong(); Na$.VT
} $K.DLqDt
input.close(); ZC]|s[
} 6f2?)jOW^N
catch(IOException e){e.printStackTrace ();} et2;{Tb,5
catch(Exception e){e.printStackTrace ();} X%mga~fB
} r+8)<Xt+p
yAAV,?:o[
5o0n4W
private void processErrorCode(int nErrorCode) #SKC>MGz
{ ~!S/{Un
System.err.println("Error Code : " + nErrorCode); mPU}]1*p
} @F]w]d
IsmZEVuC
hraR:l D
//停止文件下载 eR4ib-nS
public void siteStop() OK)>QGl
{ wz1nV}
bStop = true; -oUGmV_
for(int i=0;i<nStartPos.length;i++) #|K{txC
fileSplitterFetch.splitterStop(); tm/=Oc1p
,4S[<(T"
vf zC2
} ~j>yQ%[v
} 9N `WT=
//负责部分文件的抓取 X!:J1'FE
**FileSplitterFetch.java #]dq^B~~
*/ gg.]\#3g
package NetFox; i}:hmy'
[(2^oTSRaq
fP:]s@$
import java.io.*; mKjTJzS
import java.net.*; Ell14Iki
5kGQf
w[F})u]E
public class FileSplitterFetch extends Thread { 8nng^
=/}Rnl+c
!uit
String sURL; //File URL oKYa?
long nStartPos; //File Snippet Start Position 8o[gzW:Q)U
long nEndPos; //File Snippet End Position HU'w[r6a
int nThreadID; //Thread's ID k,$/l1D
boolean bDownOver = false; //Downing is over |fywqQFq
boolean bStop = false; //Stop identical bfpeK>T
FileAccessI fileAccessI = null; //File Access interface 3b\s;!
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J90:c@O"w
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Q>\Ho'
{ A1F$//a
this.sURL = sURL; T9}~]zW7P
this.nStartPos = nStart; qSlo)aP
this.nEndPos = nEnd; YzQ(\._s
nThreadID = id; K>vl o/#!
fileAccessI = new FileAccessI(sName,nStartPos);//定位 L*dGo,oN
} @Co6$<
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public void run() %f'=9pit
{ gxmo 1
while(nStartPos < nEndPos && !bStop) I{0cnq/
{ !@])Ut@tN
0ETT@/)]z
'.<iV!ZdZ
try{ p7 !y#
URL url = new URL(sURL); X $V_
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); G62;p#
httpConnection.setRequestProperty("User-Agent","NetFox"); >?OUs>}3y2
String sProperty = "bytes="+nStartPos+"-"; T u%XhXl:j
httpConnection.setRequestProperty("RANGE",sProperty); &"WgO!pzD
Utility.log(sProperty); >]anTF`d
}cI-]|)|2
vs$h&o>|
InputStream input = httpConnection.getInputStream(); 0C.5Qx
//logResponseHead(httpConnection); sxA]o|
\pkK >R
cuH5f}oc
byte[] b = new byte[1024]; EZ{{p+e^
int nRead; 5Pq6X
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 9od c :
{ tK[o"?2y
nStartPos += fileAccessI.write(b,0,nRead); lwfM>%%N
//if(nThreadID == 1) PYC
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); )Nx*T9!Q
} wh8;:<|
QnOs8%HS-
ZQym8iV/
Utility.log("Thread " + nThreadID + " is over!"); ViyG%Sm
bDownOver = true; 7XT(n v
//nPos = fileAccessI.write (b,0,nRead); IJKdVb~
} c~/poFj
catch(Exception e){e.printStackTrace ();} O7_y QQAA
} G /$+e
} 5FuV=Yuc
J/D~]U
v(R^LqE
//打印回应的头信息 f+ZOE?"
public void logResponseHead(HttpURLConnection con) U\,N
{ :R +BC2x
for(int i=1;;i++) FWU>WHX
{ -(e=S^36
String header=con.getHeaderFieldKey(i); N%'(8%;
if(header!=null) [kpQ:'P3
//responseHeaders.put(header,httpConnection.getHeaderField(header)); >r C*.
Utility.log(header+" : "+con.getHeaderField(header)); 6W
else so1
break; /eU\B^k
} KPDJ$,:
} a * CXg.i
/2E Q:P
-O,:~a=*_
public void splitterStop() S&-F(#CF^
{ H"A@Q.'
bStop = true; w2V:x[
} $<XQv$YS
KztQT9kY
Sh5)36
} fQ"Vx!
0}`.Z03fy
[_`yy
/* !-n*]C
**FileAccess.java >);M\,1\I
*//文件访问(定位，写) sw}^@0ua=
package NetFox; ^i8biOSZu
import java.io.*; rN7JJHV
-K$ugDi
zt9A-% \R
public class FileAccessI implements Serializable{ 9=6BQ`u
UroC8Tm
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 =bP<cC=3b
RandomAccessFile oSavedFile; Im-qGB0C
long nPos; K:qc "Q=C
vol (%wB
},}g](!m
public FileAccessI() throws IOException t~dK\>L
{ h+!R)q8M
this("",0); wj0_X;L
} LjEMs\P\
+:jv )4^O
6Y6t.j0vN.
public FileAccessI(String sName,long nPos) throws IOException w;(=wN\
{ q&3(yhx
oSavedFile = new RandomAccessFile(sName,"rw"); _*g.U=u
this.nPos = nPos; Z8/.I
oSavedFile.seek(nPos); ^V9|uHOJoq
} 4_CL1g
=aQlT*n%3
DWx;cP8[
public synchronized int write(byte[] b,int nStart,int nLen) gaNe\
{ 8"NPj0
int n = -1; {/N8[?zML
try{ ge%QbU1J
oSavedFile.write(b,nStart,nLen); 4Ozcs'}
n = nLen; DzA'MX
} u+z
catch(IOException e) W`oyDg,D
{ .waj.9&[l
e.printStackTrace (); [~cz|C#
} K0o${%'@7
wpC.!T
ki2`gLK
return n; =zrfh-lwH
} @c"s6h&
eHGx00:
:5&UWL|
} \+/ciPzA-
thX4-'i
90Sras>F
/* bQ 0Ab"+D
**SiteInfoBean.java [e_csQ
*/ Voq/0,d
package NetFox; J(~1mIJjC
z[Qe86L
<C;TGA
public class SiteInfoBean { 0t"Iq71/
m~W[,7NE0&
0 |?N
private String sSiteURL; //Site's URL 1^GRUbOU[
private String sFilePath; //Saved File's Path @q>#]8
private String sFileName; //Saved File's Name b KIL@AI
private int nSplitter; //Count of Splited Downloading File %qE"A6j
FL^t}vA
&;r'JIp
public SiteInfoBean() ^ T`T?*h
{//nSplitter的缺省值为5 *qLk'<
//default value of nSplitter is 5 mea} 9]c
this("","","",5); @x A^F%(
} :yi} CM4
Q3$DX,8?
lfd-!(tXD
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) v$JW7CKA
{ v+trHdSBYE
sSiteURL= sURL; cUd>ahv
sFilePath = sPath; 8'qlg|{!~
sFileName = sName; j"pyK@v2B
this.nSplitter = nSpiltter; 5! +{JTXa
n)D
=;Co0Q`
} XhWo~zh"
BG.8 q4[
c3c3T`B
public String getSSiteURL() r58<A'#
{ 3m-g-
return sSiteURL; {%P2.:
} 9AQ,@xP|
`m#G'E I
`(P71T
public void setSSiteURL(String value) x;} 25A|
{ _(~E8g
sSiteURL = value; UQYHR+
} *V+,X
xC0y2+)|
R-,L"Vv
public String getSFilePath() ,z`D}<3
{ <}c7E3Uc
return sFilePath; vpdPW%B
} :f_oN3F p
0yMHU[):~
%z-so?gF
public void setSFilePath(String value) 7Lj:m.0O^
{ 7PUy`H,&
sFilePath = value; 7i02M~*uS
} '^7UcgugB
*A}td8(
U,fPG/9
public String getSFileName() vo)W ziHh
{ (Nd)$Oq[4
return sFileName; hPGDN\#LD
} "s_S!;w@
<HS{A$]
MYz!zI
public void setSFileName(String value) eAjR(\f>
{ 63$`KG3
sFileName = value; lZ2gCZ
} 55] MRv
u WdKG({][
cG@Wo8+
public int getNSplitter() kJNg>SN*@#
{ ni )G
return nSplitter; C{G=Y[?oc
} -{z[.v.p
=JPY{'VO
on5\rY<I:@
public void setNSplitter(int nCount) SJ;{ Hg
{ _F4=+dT|
nSplitter = nCount; 2S[:mnK
} @7Ln1v
} `qCL&(`%
.A6pPRy e
9asA-'fZ
/* H0t#J
**Utility.java -=UvOzw
*/ K9VP@[zbJ
package NetFox; UMFM.GI
pa?AKj]
87)/dHc
public class Utility { T-7(3#&
\)aFYDq#\
j':<7n/A
public Utility() Pd `~#!
{ xH,e$t#@@~
0lOan
4W E)2vkS
} $ER$|9)KD
_Vt9ckaA
//线程睡眠 +~,q"6
public static void sleep(int nSecond) \FCPD.2s+
{ i/!KUbt
try{ S?D]P'<
Thread.sleep(nSecond); 2pSp(@N3
} ^AZv4H*~
catch(Exception e) =dQF}-{!
{ gd7!+6
e.printStackTrace (); 0Am\02R.C,
} y0) mBCX
} Zk|PQfi+
!kh:zTP
//日志 <9$Pl%:
public static void log(String sMsg) +I*a=qjq
{ u'T>Y1I
System.err.println(sMsg); 8W7ET@`
} YETGq-
W!=ur,F+
UQ)^`Zj
public static void log(int sMsg) %Br1b6 V
{ w=ufJRj
System.err.println(sMsg); )lUocm
} [3tU0BU"
} ICG:4n(,
}h3[QUVf%
jsKKg^g
/* I.SMn,N
**TestMethod.java GFnwj<V+{
*/ m5P@F@
package NetFox; 1NrNTBI@
rV-Xsf7Z
v!n|X7
public class TestMethod { 9Nz}'a;?>
cb. -AlqQ
1n.F`%YG
public TestMethod() &,,:pL[
{ ///xx/weblogic60b2_win.exe 4JH^R^O<n
try{ U:PtRSdn!b
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 9"M-nH*<
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); -&%! 4(Je
SiteFileFetch fileFetch = new SiteFileFetch(bean); +lf`Dd3
fileFetch.start(); 9%MgAik(
} $}0\sj%
catch(Exception e){e.printStackTrace ();} nVP|{M
Udjn.D
jG#e%`'
} gS|6,A9
%hz5)
Y%(8'Ch
public static void main(String[] args) 3_{rXtT)'
{ usi3z9P>n
new TestMethod(); #nj;F'O](
} z\WyL;
} ScT{Tb]9bt
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