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&tB|,W,
} QlRoe|{
for(int i=0;i<nEndPos.length-1;i++) X<Th{kM2
{ 2B9i R
nEndPos = nStartPos[i+1]; ovDJ{3L6O
} t8DL9RW'
nEndPos[nEndPos.length-1] = nFileLength; &>W (l.
} LmXF`Y$
} xMNNXPz(
vcw>v={x
+dCDM1{_a
//启动子线程 xBL$]>
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; b'7z DZI]
for(int i=0;i<nStartPos.length;i++) |k`f/*
{ *,W!FxJ
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), c/<Sa|'
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), $"sq4@N
nStartPos,nEndPos,i); g=FDm*
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 5?5-;H
fileSplitterFetch.start(); wc7mJxJxA
} #*Yi4Cn<
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Y^f94s:2S
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); $!|8g`Tm
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", jD'
nEndPos = " + nFileLength); JO2ZS6k[
// fileSplitterFetch[nPos.length-1].start(); 7b&JX'`Mb
#+K Kvk
)D["M$ZA^
//等待子线程结束 af<NMgT2s~
//int count = 0; IpWy)B>Fl3
//是否结束while循环 $hjP}- oUX
boolean breakWhile = false; M&qh]v gC
'dIX=/RZ
v[{8G^Z}54
while(!bStop) Fl_dzh,E
{ sK`~Csb iB
write_nPos(); n#+%!HTh
Utility.sleep(500); %RQC9!
breakWhile = true; x">W u2
m]FaEQVoE
.KLm39j(
for(int i=0;i<nStartPos.length;i++) .M9d*qp`S
{ }+91s'/c
if(!fileSplitterFetch.bDownOver) >=-GD2WK
{ h4CTTe)
breakWhile = false; =tr1*s{
break; RzA2*]%a
} E`Jp(gK9F
} &W=V%t>Z
if(breakWhile) <w0NPrS]
break; -{X<*P4p
ixIV=#
4%g6_KB
//count++; P%zH>K
//if(count>4) _0'm4?"
// siteStop(); b8J@K"
} Y{B9`Z
RAIVdQ}.Z
1.# |QX
System.err.println("文件下载结束！"); 7 I_1 #O
} dB@Wn!Y
catch(Exception e){e.printStackTrace ();} m#oh?@0}
} )W&o?VRfO
GWF/[%
EY+/.=$x
//获得文件长度 XR*Q|4
public long getFileSize() QS3U)ZO$@
{ ]43alf F#
int nFileLength = -1; uYFMv=>j
try{ %1Bn_
URL url = new URL(siteInfoBean.getSSiteURL()); [Q4_WKI0T
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Q)09]hP[Xj
httpConnection.setRequestProperty("User-Agent","NetFox"); j*uXB^4
)^4ko
3gb|x?
int responseCode=httpConnection.getResponseCode(); J+Q+&-a
if(responseCode>=400) P!kw;x
{ \Sg<='/{L;
processErrorCode(responseCode); kTnOmAw
return -2; //-2 represent access is error >qR7'QwP
} sK+ (v
*_`76`cz%X
&^V~cJ
String sHeader; _i5mC,OffN
U?gl"6x
tbtI1"$
for(int i=1;;i++) C>.e+V+':
{ 9|' |BC
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); >; aCf#q
//Utility.log(in.readLine()); |#{-.r6Y]
sHeader=httpConnection.getHeaderFieldKey(i); EQ4#fAM)
if(sHeader!=null) 'eDJ@4Xm
{ 9]"S:{KSCn
if(sHeader.equals("Content-Length")) ac9qj
{ v @:~mwy
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); kr%2w
break; XC=%H'p
} Y[2Wt%2\6
} m23+kj)+VY
else g3Z:{@m
break; l :/&E 6 9
} ,Du@2w3Cq
} N;uUx#z
catch(IOException e){e.printStackTrace ();} ?a S%
catch(Exception e){e.printStackTrace ();} 4t04}vp
`>s7M.|X
CdY8#+"
Utility.log(nFileLength); ]<1HM"D
F8H'^3`b`U
WvujcmOf
return nFileLength; U#bl=%bF
} #O"
["}A S:
P''X_1oMC
//保存下载信息（文件指针位置） +noZ<KFW "
private void write_nPos() S=' wJ@?;
{ Ht#@'x
try{ zF8'i=b&
output = new DataOutputStream(new FileOutputStream(tmpFile)); PocYFhWQ`
output.writeInt(nStartPos.length); qD#VbvRc9+
for(int i=0;i<nStartPos.length;i++) bp#:UUO%S
{ 2R]&v;A
// output.writeLong(nPos); J{`eLmTu
output.writeLong(fileSplitterFetch.nStartPos); !22yvT.;[
output.writeLong(fileSplitterFetch.nEndPos); SyO79e*t
} h{k_6ym
output.close(); h4/X 0@l`
} tAjx\7IX
catch(IOException e){e.printStackTrace ();} b.b@bq$1
catch(Exception e){e.printStackTrace ();} 2jl)mL
} bLqy!QE
B$^7h!
R[LsE^
//读取保存的下载信息（文件指针位置） i(*I@ku
private void read_nPos() *5e+@rD`
{ Bd@'e7{
try{ 3J{vt"dS
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ZQ3_y $
int nCount = input.readInt(); %r;w;`/hA
nStartPos = new long[nCount]; ?vgH"W~3>
nEndPos = new long[nCount]; NBjeHtT
for(int i=0;i<nStartPos.length;i++) m#f{]+6U
{ z%1{
nStartPos = input.readLong(); 9I`Y-D
nEndPos = input.readLong(); *:_P8G;
} Q/ZkW
input.close(); +R6a}d/K
} n-o3
catch(IOException e){e.printStackTrace ();} eWvo,4
catch(Exception e){e.printStackTrace ();} \hlR]m!C
} /-4$7qd
oE?QnH3R
3xNMPm
private void processErrorCode(int nErrorCode) Q$ri=uB;+
{ >`'O7.R
System.err.println("Error Code : " + nErrorCode); e}0:"R%E
} >xu[q\:"
O oSb>Y/4
A5fwAB
//停止文件下载 Ue*C>F
public void siteStop() #eK=
{ ow6*Xr8eQ
bStop = true; ]JE TeZ^/
for(int i=0;i<nStartPos.length;i++) Z{R[Wx
fileSplitterFetch.splitterStop(); kS :\Oz\
%+-C3\'
{f/]5x(_
} w~Ff%p@9
} 5Y\!pf7SQ|
//负责部分文件的抓取 f[sF:f(zI
**FileSplitterFetch.java >^$2f&z
*/ LO:fJ{ -
package NetFox; \*0yaSQF
'Z&;uv,l
e-5?p~>
import java.io.*; _q?<at}y
import java.net.*; 3= -pG
C+{l7QT$t
(\a6H2z8l
public class FileSplitterFetch extends Thread { uj|BQ`k
w$|l{VI
FP^{=0
String sURL; //File URL B*1W`f
long nStartPos; //File Snippet Start Position 6rN(_Oi-
long nEndPos; //File Snippet End Position [xb]Wf
int nThreadID; //Thread's ID tMp=-"
boolean bDownOver = false; //Downing is over %7hB&[ 5
boolean bStop = false; //Stop identical J*fBZ.NO
FileAccessI fileAccessI = null; //File Access interface ILwn&[A0
otJ!UfpR8
($nrqAv4
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ~8T(>!hE1h
{ ,8MLoZ_
this.sURL = sURL; BZv+H=b
this.nStartPos = nStart; v"^~&q0x
this.nEndPos = nEnd; oU6y4yO
nThreadID = id; gEQNs\Jn L
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ]bi)$j.9s
} 1w(JEqY3h:
xI*#(!x"G
DI|:p!Nx
public void run() L,,*gK
{ ]aryV?!6
while(nStartPos < nEndPos && !bStop) JUAS$Y
{ ~z5R{;Nbz|
8>WVodv
fV:4#j
try{ D4JLtB'=
URL url = new URL(sURL); TXXy\$
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 4Kwh?8.
httpConnection.setRequestProperty("User-Agent","NetFox"); WQNE2Q
String sProperty = "bytes="+nStartPos+"-"; f:B>zp;N
httpConnection.setRequestProperty("RANGE",sProperty); ;Lm=dd@S:
Utility.log(sProperty); 5kNzv~4B,;
SLfFqc+n0
'CZa3ux
InputStream input = httpConnection.getInputStream(); X|D!VX>#!
//logResponseHead(httpConnection); YW\0k5[
R%D'`*+
U$dh1;
byte[] b = new byte[1024]; h].~#*
int nRead; COzyG.R.
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) `(6r3f~XJ
{ G rmzkNlN
nStartPos += fileAccessI.write(b,0,nRead); kql0J|P?
//if(nThreadID == 1) YXurYwV
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Em 6Qe
} bI)u/
Wo~vhv$E
ig LMv+{
Utility.log("Thread " + nThreadID + " is over!"); }N0Qm[R
bDownOver = true; PQKaqv}N
//nPos = fileAccessI.write (b,0,nRead); .`<@m]m-
} SUKxkc(
catch(Exception e){e.printStackTrace ();} qn1255fB
} Vm}%ttTC
} bwM@/g%DL
!o=U19)
}]n$ %g(
//打印回应的头信息 +Q=1AXe
public void logResponseHead(HttpURLConnection con) `LAR@a5i
{ l {jmlT
for(int i=1;;i++) ?{w3|Ef&
{ jcNT<}k C
String header=con.getHeaderFieldKey(i); Uy ?
if(header!=null) ;w|b0V6
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ]lw|pvtd
Utility.log(header+" : "+con.getHeaderField(header)); n+lOb
else yme^b ;a
break; {!|}=45Z
} DrnJ;Hi"
} m-^8W[r+_
Y)N-V ]5L
o&AM2U/?
public void splitterStop() ac kqH+'
{ P`s
bStop = true; -/{4Jf Wf
} x3qW0K8
pj4!:{.;
>9RD_QG7
} {u1V|q
aLJ(?8M@
)ZrS{vY
/* :=%0Mb:
**FileAccess.java o?1;<gs
*//文件访问(定位，写) Xc"&0v%;#
package NetFox; `(A5f71MfM
import java.io.*; PP:(EN1
pfu1O6R
1]IQg;q
public class FileAccessI implements Serializable{ x+f2GA$
5JEbe
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 DvvT?K
RandomAccessFile oSavedFile; `n$5+a+
long nPos; V $z} K
=@k%&* Y?
upj]6f"(
public FileAccessI() throws IOException .h0b~nI>>
{ &>e-(4Xu
this("",0); N2.AKH
} :Mm3 gW)
zIP6\u
,g%&|FAP
public FileAccessI(String sName,long nPos) throws IOException 5~mh'<:
{ meN2ZB?Y
oSavedFile = new RandomAccessFile(sName,"rw"); Z|%_oR~b|
this.nPos = nPos; ;<G=M2
oSavedFile.seek(nPos); T3`ludm^u
} tmqY2.
Y0D}g3`
ynA|}X
public synchronized int write(byte[] b,int nStart,int nLen) h3dsd
{ &WNf M+
int n = -1; JaB<EL-9r2
try{ Gmf B
oSavedFile.write(b,nStart,nLen); lA>DS#_
n = nLen; f!O{%ev
} )(y)A[
catch(IOException e) pb#?l6x$+
{ r5!/[_l
e.printStackTrace (); CHV*vU<N
} Q#nOJ(KV
,V*%V;
R+&jD;U{
return n; !Hys3AP
} x\Z'2?u}
5) -~mWy
pp7$J2s+j
} 5]M>8ll
C@jJ.^ <<
$.9{if#o&
/* XJLQ{
**SiteInfoBean.java gY@N~'f;"
*/ J>u 7,
package NetFox; {uGP&cS~(
6xD#?
hEh}PX:
public class SiteInfoBean { w`q%#qRk
ew"v{=X
e9Nk3Sj]
private String sSiteURL; //Site's URL ID#I`}h.k
private String sFilePath; //Saved File's Path meOMq1
private String sFileName; //Saved File's Name k?2k'2dy
private int nSplitter; //Count of Splited Downloading File 61xs%kxb..
rk)##)
Q>n|^y6
public SiteInfoBean() MNSbtT*^
{//nSplitter的缺省值为5 |=&cQRY!p
//default value of nSplitter is 5 %;.;>Y(-
this("","","",5); @:KJYm[
} 26xXl|I
/="~gq@
{dmj/6Lc
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 6ND`l5
{ 2 !'A:;
sSiteURL= sURL; n> ^[T[.S
sFilePath = sPath; <Qxh)@ N
sFileName = sName; gks{\H]
this.nSplitter = nSpiltter; CZ nOui
$z+8<?YD
cK 06]-Y
} =b/L?dR.-
=2@B&
A'2w>8
public String getSSiteURL() a{[x4d,z
{ 6P';DB
return sSiteURL; U^Xm)lL
} )HX|S-qRU=
+zy=50,
D}vmwg@3
public void setSSiteURL(String value) gB<3-J1R
{ 9Lr'YRl[W
sSiteURL = value; `3:.??7N
} T8^5=/
< P`u}
4Z/f@ZD
public String getSFilePath() YX`7Hm,
{ P{u0ftyX}
return sFilePath; '3?\K3S4i
} 5< ja3
zL\OB?)5J
*6} N =Z
public void setSFilePath(String value) hcyM6:}
{ /c,(8{(O
sFilePath = value; lg(bDKm
} *k19LI.5
hXA6D)
Aj0Tfdxy
public String getSFileName() 2 aL)
{ mQY_`&Jq
return sFileName; e#E2>Bj;
} lEV]4 t_H
9-rNw?7
0=K9`=5d0
public void setSFileName(String value) rta:f800z
{ -N"&/)
sFileName = value; 1|ra&(=)
} # 0Lf<NZ
;s52{>&F]
9k6r_G"
public int getNSplitter() ^.>jGI%rB
{ (7r<''
return nSplitter; }X=[WCKU
} ?yj6CL(,
Pcw6!xH
LGl2$#x
public void setNSplitter(int nCount) (<)]sp2
{ AhNq/?Q Q~
nSplitter = nCount; xe*aC
} AW,53\ 0
} 5:kH;/U
#b~JDO(
m'f,_ \'
/* CjiVnWSz<
**Utility.java d$ ^ ,bL2p
*/ gmm|A9+tv
package NetFox; >Bgw}PI
X@f "-\
VP6ZiQ|
public class Utility { yUp,NfS]o
nH<eR)0
'z[Sp~I\
public Utility() SGe^ogO"v
{ a|?4)
>hr{JJe
WH= EPOR,
} u&n' ITH
uh?>- ]r`
//线程睡眠 BN4_:
public static void sleep(int nSecond) l'3pQ;
{ Q*b]_0Rb
try{ *q1%IJ
Thread.sleep(nSecond); ;dzL}@we
} /jRRf"B
catch(Exception e) kbMYMx.[
{ Oj^,m.R
e.printStackTrace (); Q_Gi]M9
} /IM#.v
} ,j$Vvz
L\#<JxY$p
//日志 3l#IPRn9AO
public static void log(String sMsg) di>cMS 4 c
{ L*~J%7
System.err.println(sMsg); 19j+lCSvH
} 8f3vjK'
YWxc-fPZ
UNkCL4N
public static void log(int sMsg) l'TWkQ-
{ \xS&v7b
System.err.println(sMsg); ]~E0gsq
} ivW(*c
} tz&y*e&
aG92ay
afb+GA!
/* <Ce2r"U1e
**TestMethod.java $]A/ o(
*/ uECsh2Uin
package NetFox; Gqy,u3lE
F 3'9u#
H `(exa:w
public class TestMethod { $O dCL
gR}35:$Z-
1)[]x9]^q'
public TestMethod() G3{=@Z1
{ ///xx/weblogic60b2_win.exe ~R@Nd~L
try{ )}_a 0bt
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); XQ~Ke-QW)
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); H[='~%D
SiteFileFetch fileFetch = new SiteFileFetch(bean); 4`8<
fileFetch.start(); r!{LLc}>
} hc'-Dh
catch(Exception e){e.printStackTrace ();} %Pqf{*d8
6O}`i>/6M
J|w)&bV
} m:/wG& !
MC{ 2X
44F`$.v96
public static void main(String[] args) Rh>}rGvCUN
{ F<(i.o(
new TestMethod(); Z%x\~)~
} ]hbyELs
} ._+J_ts
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