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)); KgkB)1s@n
} tYxlM!
for(int i=0;i<nEndPos.length-1;i++) iegPEb
{ U";Rp&\3;
nEndPos = nStartPos[i+1]; Lm2cW$s
} ~d1RD
nEndPos[nEndPos.length-1] = nFileLength; i3\oy`GJ
} ^K@GK
} PyJblW
m`w6wz
oFA$X Y
//启动子线程 ^{,}, i
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; (IWd?,H,n
for(int i=0;i<nStartPos.length;i++) e}@J?tJK.L
{ x-P_}}K 79
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), W;j)ux7jMY
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), RB 0j!H:
nStartPos,nEndPos,i); "e?#c<p7
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ?q8g<-?
fileSplitterFetch.start(); a*@Z^5f
} l%V}'6T
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), zL=I-fVq
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); e5y`CXX
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", O?<_,-.
nEndPos = " + nFileLength); yD'h5)yu
// fileSplitterFetch[nPos.length-1].start(); W5yu`Br
= ft$j
YXOD fd%L
//等待子线程结束 (3S/"ZE
//int count = 0; J*k=|+[
//是否结束while循环 LA3,e (e
boolean breakWhile = false; nmAXU!t'
,S K6*tpI
~H."{
while(!bStop) `qEm5+`
{ |/ 7's'
write_nPos(); M& L0n%,y5
Utility.sleep(500); D*b|(Oi
breakWhile = true; '\qr=0aW
FX%E7H
:jCaDhK
for(int i=0;i<nStartPos.length;i++) JG$J,!.\
{ vIv3rN=5vB
if(!fileSplitterFetch.bDownOver) rI$10R$+H
{ /v<8x?=
breakWhile = false; 2,`mNjHh
break; ;hp; Rd
} 'KrkCA
} cMKh+r
if(breakWhile) 5Uz(Bi
break; Qc/J"<Lx
+#9 (T
LLN^^>5|l
//count++; msJn;(Pn
//if(count>4) ioQlC4Y
// siteStop(); G*V 7*KC
} NsK>UJ'
nr6U> KR^
jl7-"V>j?;
System.err.println("文件下载结束！"); KL{uhb0f
} &WS%sE{p_
catch(Exception e){e.printStackTrace ();} =i<(hgD
} )^3655mb
1.CYs<
G9%4d;uFT
//获得文件长度 fQ) ;+
public long getFileSize() wEqCuhZ
{ 6f1Y:qK'@
int nFileLength = -1; (b5af_ c
try{ >@W#@W*I@
URL url = new URL(siteInfoBean.getSSiteURL()); KLB?GN?Pb
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ax}Xsk_
httpConnection.setRequestProperty("User-Agent","NetFox"); ]P5u:~U
BGOI
YkbLf#2AE|
int responseCode=httpConnection.getResponseCode(); KO7cZME
if(responseCode>=400) bBL"F!.
{ \6L=^q=
processErrorCode(responseCode); P40eK0e6
return -2; //-2 represent access is error v-@@>?W-
} j$Co-b1
rZ7 Ihof
%&NK|M+n
String sHeader; *?\Nioii
<#Dc(VhT
T9yW# .
for(int i=1;;i++) %UhF=C
{ c7 -j
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); |&.)_+w
//Utility.log(in.readLine()); 4T-AWk
sHeader=httpConnection.getHeaderFieldKey(i); l"Q8`
if(sHeader!=null) \U8Vsx1tl
{ 2q bpjm
if(sHeader.equals("Content-Length")) (6b%;2k
{ w0SgF/"@
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); z9ZAY!Zhq]
break; nz+KA\iW
} S{06bLXU"
} 4v7RX
else ujedvw;sO
break; (Nf.a4O
} it@s(1EO#
} &,xM;8b
catch(IOException e){e.printStackTrace ();} x~.U,,1
catch(Exception e){e.printStackTrace ();} Zl*!pQ
~heF0C_
bzS [X
Utility.log(nFileLength); agzG
YXEZ&$e'
ycN_<
return nFileLength; I._=q
} a;sZNUSn
?u|g2!{_
>F v8 -
//保存下载信息（文件指针位置） AseY.0
private void write_nPos() {cFei3'q
{ dLq!t@?iu>
try{ <Lt$qV-#
output = new DataOutputStream(new FileOutputStream(tmpFile)); "lt[)3*
output.writeInt(nStartPos.length); PE>_;k-@k
for(int i=0;i<nStartPos.length;i++) 5s9~rm
{ qZ.\GHS
// output.writeLong(nPos); 9"e!0Q40
output.writeLong(fileSplitterFetch.nStartPos); Y|L57F
output.writeLong(fileSplitterFetch.nEndPos); wl4yNC
} S/|8'x{<
output.close(); ]Yy Sf
} D3OV.G]`
catch(IOException e){e.printStackTrace ();} @\a- =
catch(Exception e){e.printStackTrace ();} X"]ZV]7(]s
} 'n=D$j]X
?.H*!u+9>
m,b<b91
//读取保存的下载信息（文件指针位置） ~[{| s')
private void read_nPos() 9azPUf) C
{ J.*=7zmw
try{ w~`P\i@
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ZJqmD
int nCount = input.readInt(); R!=XMV3$PH
nStartPos = new long[nCount]; >8##~ZuF+
nEndPos = new long[nCount]; v3B ^d}+.
for(int i=0;i<nStartPos.length;i++) /[p4. FL
{ ?w+T_EH
nStartPos = input.readLong(); Hs9uDGWp
nEndPos = input.readLong(); RB!g,u
} sQkP@Y
input.close(); [,c>-jA5
} NTC,Vr\A
catch(IOException e){e.printStackTrace ();} PSE![whK
catch(Exception e){e.printStackTrace ();} 7?4>'
} Ni`qU(I'|
1/ HofiIa
Je'$V%{E
private void processErrorCode(int nErrorCode) KK?}`o
{ n1ICW 9
System.err.println("Error Code : " + nErrorCode); @'QBrE
} 7Vi[I< *
ZO,]h9?4
_Cs.%R!r
//停止文件下载 -(jcsqDk
public void siteStop() $_y"P
{ $I'ES#8P6
bStop = true; u=4Rn
for(int i=0;i<nStartPos.length;i++) })":F
fileSplitterFetch.splitterStop(); >y?$aJ8ZV
<K43f#%
Bn.8wMB
} l}m@9 ~oC
} 8WvT0q>]
//负责部分文件的抓取 }\@*A1*X2
**FileSplitterFetch.java ~Oq(JM $M
*/ )9*WmFc+#
package NetFox; *]LM2J
5b&'gd^d
30<^0J.1
import java.io.*; bV"0}|A~K
import java.net.*; YRK4l\_`
=hA/;
/q=<OEC
public class FileSplitterFetch extends Thread { ^71sIf;+
)3;S;b
$V[ob
String sURL; //File URL 9]Y@eRI<
long nStartPos; //File Snippet Start Position UZyo:*yB
long nEndPos; //File Snippet End Position O_E[FE:+
int nThreadID; //Thread's ID {AZW."?
boolean bDownOver = false; //Downing is over *+b[v7
boolean bStop = false; //Stop identical Zffzyh
FileAccessI fileAccessI = null; //File Access interface yEH30zSt
@A:Xct
/h_BF\VBs
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException n@*NQ`(_
{ 0j*8|{|
this.sURL = sURL; WPPmh~:
this.nStartPos = nStart; g;-CAd5
this.nEndPos = nEnd; H]SnM'Y
nThreadID = id; 7&X^y+bMe6
fileAccessI = new FileAccessI(sName,nStartPos);//定位 9N9;EY-U
} k]v a
hgm`6TQ
Uu G;z5
public void run() N(D_*% 96
{ mF "ctxE
while(nStartPos < nEndPos && !bStop) ;&iQNXL
{ [g<JP~4]
/vBpRm
HxkhlNB
try{ spJB6n(
URL url = new URL(sURL); #q%&,;4
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); c(o8uWn
httpConnection.setRequestProperty("User-Agent","NetFox"); YYhRdU/g
String sProperty = "bytes="+nStartPos+"-"; GSypdEBj+w
httpConnection.setRequestProperty("RANGE",sProperty); Pd>hd0!.%
Utility.log(sProperty); <@oK^ja
2 Y%$6NX
A;h~Fx6s
InputStream input = httpConnection.getInputStream(); :}Z+K*%o-
//logResponseHead(httpConnection); ,9=a(j"
!fZxK CsQ
8NpQ"0X
byte[] b = new byte[1024]; :=-h'<D
int nRead; =>4,/g3
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 'peFT[1>(
{ Yk:\oM
nStartPos += fileAccessI.write(b,0,nRead); >I+O@
//if(nThreadID == 1) NJ3b Oq
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Pj^6.f+
} a6[bF
'y@0P5[se
#*5A]"k
Utility.log("Thread " + nThreadID + " is over!"); m,'u_yK
bDownOver = true; gQ&FO~cr
//nPos = fileAccessI.write (b,0,nRead); w!h!%r
} [$B
catch(Exception e){e.printStackTrace ();} @zE_fL
} CB|Z~_Bm
} gVA$P
KN5.2pp
[}.OlR3)
//打印回应的头信息 ]GRPxh
public void logResponseHead(HttpURLConnection con) nNf/$h#;O
{ o: qB#8X
for(int i=1;;i++) \T>f+0=4
{ \!`*F:7]-
String header=con.getHeaderFieldKey(i); gJ:Z7b
if(header!=null) jytfGE:
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ZfS-W&6Z
Utility.log(header+" : "+con.getHeaderField(header)); {,,w5/k^
else 6:@tHUm
break; uS3J^=>@(a
} [@Y?'={qE
} 7|*|xLrVY
bq]af.o*
0Bb amU
public void splitterStop() N_h)L`
{ 2UA h^i-^
bStop = true; flnoK%wi
} RaKL KZn
s@Y0"
Q@nxGm
} 1jO/"d.8n
Za5*HCo
Gw$U0HA[,
/* o^biO!4,
**FileAccess.java 0fwo8NgX
*//文件访问(定位，写) T-uI CMEf
package NetFox; 5_#wOz0u$
import java.io.*; Y ~xcJH
c=h{^![$
\f05(ld
public class FileAccessI implements Serializable{ o=7 -&F.
_=}Efy7
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 t /1KKEZM
RandomAccessFile oSavedFile; }hhDJ_I5M
long nPos; V\Cu|m&HI
Sm{idky)[
["kk.*&
public FileAccessI() throws IOException uveTx
{ AKejWh
this("",0); {O[a+r.n
} N.l+9L0b
7&qunK'
KYZ/b8C
public FileAccessI(String sName,long nPos) throws IOException ]W]o6uo7
{ m6bAvy]3<t
oSavedFile = new RandomAccessFile(sName,"rw"); =;4cDmZh
this.nPos = nPos; \IQf|
oSavedFile.seek(nPos); %[l5){:05
} b[%sKl
+' QX`
ez@`&cJ7
public synchronized int write(byte[] b,int nStart,int nLen) ML9ZS @
{ /z.Y<xOc
int n = -1; bODCC5yL
try{ [8v v[n/
oSavedFile.write(b,nStart,nLen); sFsp`kf
n = nLen; =]K;"
} @Xts}(L
catch(IOException e) P{h;2b{
{ Mpzt9*7R
e.printStackTrace (); Usx8 U
} N`h,2!(j
:?S1#d_
9@9(zUS|
return n; !?,7Cu.5#6
} |@`F!bnLr
d,tGW
%wzDBsX
} _ fJ5z
8M<q-sn4B
d="Oge8
/* Dp3&@M"^yY
**SiteInfoBean.java <lopk('7
*/ P-o/ax
package NetFox; U-&dn%Sq
|3<tDq@+
gdPv,p19L
public class SiteInfoBean { R*|y:T,H
q$L=G
>x]b"@Hkw
private String sSiteURL; //Site's URL CoO..
private String sFilePath; //Saved File's Path gi\2bzWkbX
private String sFileName; //Saved File's Name S~X&^JvT
private int nSplitter; //Count of Splited Downloading File ~)xg7\k
M=:!d$c
,@!io
public SiteInfoBean() {]BPSj{B
{//nSplitter的缺省值为5 ek\8u`GC
//default value of nSplitter is 5 +i HZ*
this("","","",5); z~fZg6
} a~ sU
:Aj8u\3!@
GrPKJ~{6
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ieo Naq
{ HI&N&a9C
sSiteURL= sURL; xMsSZ{j%5
sFilePath = sPath; .$&mWytw=
sFileName = sName; =;Ap+}
this.nSplitter = nSpiltter; s&&8~ )H
5-qk"@E W
;\-f7!s
} O=m_P}K
v%a)nv
utOATjB.z
public String getSSiteURL() pn"TFapJA
{ Sp/t[\,'
return sSiteURL; r{2V`h1/|
} cBcfGNTJ~
9n9Z
t~_vzG
public void setSSiteURL(String value) ggn C #$
{ >1uo5,wrF
sSiteURL = value; 9bu}@#4*
} K ?uHAm
h.T]J9;9
q9+`pj
public String getSFilePath() X%JQ_Z
{ 3<F\5|
return sFilePath; .Z?@;2<l
} T<XGG_NOl
3mef;!q
8[v9|r
public void setSFilePath(String value) y950Q%B]
{ GO&~)Vh&7
sFilePath = value; b^s978qn#
} >I*)0tE
={g.Fn(_
t"# .I?S0
public String getSFileName() <9f;\+zA
{ *~Y$8!ad
return sFileName; r7|_Fm Qf
} O2;iY_P7lV
_EHz>DJ9
/Uxp5 b h
public void setSFileName(String value) y0}3s)lKv
{ fhwJ
sFileName = value; D@W[Nd5MJ
} k65V5lb
_"0,
KYw~(+gHv2
public int getNSplitter() 0c}pg:XT
{ t.\<Q#bN#
return nSplitter; Cj/J&PDQ
} ^lvYj E
bqPaXH n
lKVV*RR}
public void setNSplitter(int nCount) <[l0zE5Z8'
{ !m {d6C[
nSplitter = nCount; 1Jm'9iy3
} E^s<5BC;
} o,NTIh
ccR#<Pb6q
kz!CxI (
/* 9Gh:s6
**Utility.java +4 W6{`
*/ 3bsuE^,.@
package NetFox; u B~C8}
)70i/%}7
reP)&Fo
public class Utility { pZxuV(QP`
bT>1S2s
2|a5xTzH
public Utility() #3~hF)u&/
{ |7CFm
C(Cuk4K
y@Gl'@-O
} ^QG;:.3v
h4,g pV>t
//线程睡眠 q9 SV<qg
public static void sleep(int nSecond) ~7 w"$H8
{ kO3N.t@n
try{ )swu~Wb}U@
Thread.sleep(nSecond); X;/5Niv32q
} e0Jz|?d=
catch(Exception e) `*Ju0)g1
{ 1Zo"Xb
e.printStackTrace (); 8pXului
} /LK,:6
} 2%Mgg,/~
$-w&<U$E
//日志 "7z1V{ ;Y
public static void log(String sMsg) /_(q7:<ZF
{ w;p~|!
System.err.println(sMsg); alp}p
} P:OI]x4
k>.n[`>$6|
$n#NUPzG+
public static void log(int sMsg) ^]zC~LfG
{ ']&rPvkL
System.err.println(sMsg); `b:yW.#w3l
} Y=5}u&\
} k.n-JS
}lQ`ka
4\Q pS
/* ix+sT|>
**TestMethod.java AZH=r S`
*/ ]EWEW*'j
package NetFox; U(6=;+q
I xk+y?
MszX9wl
public class TestMethod { al1Nmc#
hk.vBbhs
$8{v_2C){
public TestMethod() y[A%EMd
{ ///xx/weblogic60b2_win.exe Q!ReA{
try{ o6ag{Yp
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); #a+*u?jnnL
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); @%b&(x^UD
SiteFileFetch fileFetch = new SiteFileFetch(bean); TbQ5
fileFetch.start(); N<e72x
} kSUpEV+/
catch(Exception e){e.printStackTrace ();} !(i}FFn{:
NpAZuISD!
X3zpU7`Av+
} 0`Hr(J`F
%8c2d
M"\j7(
public static void main(String[] args) f=--$o0U~
{ lL;SP&
new TestMethod(); J/xbMMb
} ad#4W0@S
} Oe)B.{;Ph
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