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)); P#~B@d
} +&`W\?.~
for(int i=0;i<nEndPos.length-1;i++) \%=\4%:
{ 1jl!VU6
nEndPos = nStartPos[i+1]; :;7I_tb
} G-Tmk7m
nEndPos[nEndPos.length-1] = nFileLength; St-uE|8
} XWp8[Cxs
} ~hLan&T
H0Pxw P>q
lrT2*$ w3
//启动子线程 6@J=n@J$p
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; `@h|+`h
for(int i=0;i<nStartPos.length;i++) 7w/IHML
{ &[.`xZ(|
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), v~P,OP("c
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), jV3PTU
nStartPos,nEndPos,i); I#M3cI!X?
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); A IP~A]T
fileSplitterFetch.start(); `a& kD|Yh
} Cl}nPUoL
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 1PkCWRpR
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); iEr,ly
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", @!#e\tx
nEndPos = " + nFileLength); 9Yx(u2PQ
// fileSplitterFetch[nPos.length-1].start(); 0CrsZtX
V)`2Kw
B[t^u\Fk
//等待子线程结束 $<^t][{
//int count = 0; C9n%!()>
//是否结束while循环 ,S8K!
boolean breakWhile = false; H/f}tw
C&q}&=3r
&WCVdZK:
while(!bStop) YTgT2w
{ qHrIs-NR
write_nPos(); ;8F6a:\v
Utility.sleep(500); wQ-BY"cK\
breakWhile = true; -vT$UP
KJn 3&7
M#o=.,
for(int i=0;i<nStartPos.length;i++) C#&b`
{ _ru<1n[4~
if(!fileSplitterFetch.bDownOver) z:n JN%Qb
{ 1_~'?'&^
breakWhile = false; 4pDZ +}p
break; p<VW;1bt5
} e mq%" ;.
} aBF<it>
if(breakWhile) X bV?=
break; d[(%5pw~zL
Erl@]P4
Tq6@ 1j6p
//count++; ^w RD|
//if(count>4) "MT{t><
// siteStop(); ht)KS9Xu
} =2wy;@f
i];@e]
P[cGCmM
System.err.println("文件下载结束！"); RG_)<U/B
} I'cM\^/h
catch(Exception e){e.printStackTrace ();} '$OLU[(Y
} `^E(P1oJ3
PI")^`
s&OwVQ<M
//获得文件长度 YwM;G g3
public long getFileSize() =>h~<88#5
{ |}roR{gc|
int nFileLength = -1; W/R-~C e
try{ p&\x*~6u
URL url = new URL(siteInfoBean.getSSiteURL()); |c>A3 P$=B
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Q ?W6
httpConnection.setRequestProperty("User-Agent","NetFox"); jZY9Lx8o
>^Z!
W,n0'";')
int responseCode=httpConnection.getResponseCode(); 0:Lm=9o
if(responseCode>=400) QPa&kl
{ &"svt2
processErrorCode(responseCode); ?G-a:'1!6
return -2; //-2 represent access is error \oGZM0j
} *o[*,1Pw
[!:.9
5B(r[Ni b
String sHeader; STB=#z
^Sr`)vP
{Z|.-~W
for(int i=1;;i++) e~weYGK
{ akQtre`5sd
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 3C8'@-U
//Utility.log(in.readLine()); ji2if.t@
sHeader=httpConnection.getHeaderFieldKey(i); #H1yjJQ /x
if(sHeader!=null) A! 1>
{ GRj{*zs
if(sHeader.equals("Content-Length")) 'gE_xn7j
{ 6i\b&
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 413r3/
break; Nr7MSFiL
} &e%y|{Y
} QTK{JZf
else A\.M/)Qo
break; uBs[[9je(
} ?P`]^#
} ?(U> )SvF
catch(IOException e){e.printStackTrace ();} Oy[t}*Ik
catch(Exception e){e.printStackTrace ();} < v_?}
^QV;[ha,o
}`
Utility.log(nFileLength); q^dI!93n|
<H E'5b
mrd(\&EhA
return nFileLength; ({zp$P}
} Jb {m
Cl>'K*$F
}kXF*cVg
//保存下载信息（文件指针位置） FAU^(]-5m
private void write_nPos() x_(B7ob
{ *Xl&N- 04
try{ I[<C)IG
output = new DataOutputStream(new FileOutputStream(tmpFile)); ]Wv\$JXI
output.writeInt(nStartPos.length); fX} dh9
for(int i=0;i<nStartPos.length;i++) JYKA@sZHe
{ 'n.eCdj
// output.writeLong(nPos); wTIOCj
output.writeLong(fileSplitterFetch.nStartPos); HcQ{ok9u
output.writeLong(fileSplitterFetch.nEndPos); 18ci-W#p
} eB!0:nHN
output.close(); %t%+;(M9
} S <|e/![@
catch(IOException e){e.printStackTrace ();} |'=R`@w~0
catch(Exception e){e.printStackTrace ();} d:=5y)
} )BS./zD*[<
^i#q{@g
WZ"x\K-;
//读取保存的下载信息（文件指针位置） 3Xf}vdgdM$
private void read_nPos() PGu6hV{
{ `Nu3s<O7CF
try{ =?T'@C
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Scs \nF2
int nCount = input.readInt(); ;9 XM s)
nStartPos = new long[nCount]; s'fHhG6
nEndPos = new long[nCount]; 0sk*A0HX-
for(int i=0;i<nStartPos.length;i++) i v&:X3iB
{ _i6G)u&N
nStartPos = input.readLong(); d^WVWk K
nEndPos = input.readLong(); &kRkOjuk
} .v0.wG
input.close(); =R?NOWrDY
} *V3}L Z
catch(IOException e){e.printStackTrace ();} p^7ZFUP
catch(Exception e){e.printStackTrace ();} ix$?/GlL
} JTQ$p*2]
SpjL\ p0
E,u@,= j
private void processErrorCode(int nErrorCode) R.*KaCA
{ B.;/N220P
System.err.println("Error Code : " + nErrorCode); '1|r+(q|2
} #:w/vk
=MRg
d1D{wZ3g
//停止文件下载 NHPpHY3^.
public void siteStop() u==bLl=$
{ }*hY#jo1
bStop = true; X'IW&^kI
for(int i=0;i<nStartPos.length;i++) >QU1_'1r
fileSplitterFetch.splitterStop(); ~z^VMr
|Ah26<&
h~urZXD<
} <hkg~4EKc
} a7)q^;:O
//负责部分文件的抓取 8AOJ'~$
**FileSplitterFetch.java r,A750P^
*/ ;mu9;ixZ
package NetFox; 8h78Zb&[
5<<e_n.2q
kZBIXW,G
import java.io.*; w6'o<=
import java.net.*; iXqc$!lTH
S92'\2
iKu[j)F
public class FileSplitterFetch extends Thread { `f}}z5
z%Op_Ddp
:G?"BL5vP
String sURL; //File URL &%ej=O
long nStartPos; //File Snippet Start Position cmmH)6c>
long nEndPos; //File Snippet End Position jX$TiG
int nThreadID; //Thread's ID :=UiEDN@
boolean bDownOver = false; //Downing is over 5][Rvu0
boolean bStop = false; //Stop identical l[.*X
FileAccessI fileAccessI = null; //File Access interface aEW Z*y
L~cswG'K
is}o5\JEL
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException R4"["T+L`
{ ~Us1F=i_Q
this.sURL = sURL; 9 %4Pt=v~d
this.nStartPos = nStart; kzZtKN9Az
this.nEndPos = nEnd; `zAV#
nThreadID = id; zO<EbqNe!
fileAccessI = new FileAccessI(sName,nStartPos);//定位 D9B?9Qt2[
} :c"J$wT/
I1=YSi;A
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public void run() 2lDgvug
{ [aU#"k)M
while(nStartPos < nEndPos && !bStop) S3PW[R@=
{ W1f]A#t<
f(=yC}si
j_-$xz5-
try{ ;LELC5[*s
URL url = new URL(sURL); c5>&~^~>Tx
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); -N(y+~wN
httpConnection.setRequestProperty("User-Agent","NetFox"); 9aD6mp
String sProperty = "bytes="+nStartPos+"-"; 9Xmb_@7b}
httpConnection.setRequestProperty("RANGE",sProperty); oJVpNE[3]
Utility.log(sProperty); O?p.kf{b
Nc F
)p4o4aM
InputStream input = httpConnection.getInputStream(); >Y?B(I2e
//logResponseHead(httpConnection); 2GLq#")P
3M8P%
?q1&(g]qO
byte[] b = new byte[1024]; "\Jq2vM
int nRead; ndT:,"s
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Wxkk^J9F3
{ E&}r"rbI
nStartPos += fileAccessI.write(b,0,nRead); EC&t+"=R
//if(nThreadID == 1) #s{>v$F
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Za}*6N=?*
} "Y}f"X|
Q4{%)}2$
GeWB"(t
Utility.log("Thread " + nThreadID + " is over!"); @xH|(
bDownOver = true; {J%Na&D
//nPos = fileAccessI.write (b,0,nRead); 4,tMaQ
} nS"K dPM
catch(Exception e){e.printStackTrace ();} 9*GwW&M%1_
} J?)vsnD.H
} (l{+T#
D{Y~kV|
8 Mp2MZ*p
//打印回应的头信息 J0a]Wz%
public void logResponseHead(HttpURLConnection con) eJ+;!0
{ ?{?mAbc
for(int i=1;;i++) I.r&;
{ gP/[=:
String header=con.getHeaderFieldKey(i); ~fI&F|
if(header!=null) D$q"k"
//responseHeaders.put(header,httpConnection.getHeaderField(header)); FXV=D_G}
Utility.log(header+" : "+con.getHeaderField(header)); A^q= :ofQ
else Vo+d3
break; .3?'+KZ,
} z{pNQ[t1Z
} '!Ps4ZTn_
j|FGb:
7J~6J.m
public void splitterStop() =rl/l8|P
{ Fx4C]S
bStop = true; nT`NfN
} m?'5*\(ST
FH)bE#4
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} WGN[`D"
)wP0U{7?v
o m`r^3,
/* cBmo#:>'
**FileAccess.java W=5+k0Q
*//文件访问(定位，写) daaUC
package NetFox; }U7>_b2
import java.io.*; 2n?\tOm(V
[POcO
fpM4q
public class FileAccessI implements Serializable{ -?e~dLu
)~_!u}+:(
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 V:6#IL
RandomAccessFile oSavedFile; l"}W $3]u$
long nPos; D4s*J21)D
(sS[F-2R7
reM%GU
public FileAccessI() throws IOException idGkX ?
{ {5.,gb@6
this("",0); _E)xR
} .Y_RI&B!L
86/CA[Y-
\>cZ=
public FileAccessI(String sName,long nPos) throws IOException TMKemci
{ hOfd<k\A
oSavedFile = new RandomAccessFile(sName,"rw"); 9Vzk:zOT
this.nPos = nPos; ]WN{8
oSavedFile.seek(nPos); X^_,`H@
} qw%4j9}
3=t}py7M
L]9!-E
public synchronized int write(byte[] b,int nStart,int nLen) 8Qu7x[tK?
{ IL3,dad'^
int n = -1; GK95=?f~8;
try{ T fzad2}^
oSavedFile.write(b,nStart,nLen); i= ~HXr}
n = nLen; CEYHD?9k8
} L$ ]D&f8:
catch(IOException e) RK'3b/T
{ v6s8 p
e.printStackTrace (); hx)Ed
} K_]LK
eX?o4>
Q;m .m2
return n; {zbH.V[
} o"Ef>5N
}xLwv=Ia
MuZ\<;W$
} {nryAXK
l-t:7`=|
bRNE:))r_
/* 2(\>PN-
**SiteInfoBean.java deHBY4@
*/ l,6="5t
package NetFox; U%gP2]t%cs
UY}lJHp0
S`0@fieOf
public class SiteInfoBean { He#+zE;
Oq+C<}eg
akd~Z
private String sSiteURL; //Site's URL T]CvfvO5
private String sFilePath; //Saved File's Path Kwh3SU=L}
private String sFileName; //Saved File's Name *ZN"+wf\
private int nSplitter; //Count of Splited Downloading File 6K`frt
K<|b>PI.s
m?[F)<~a
public SiteInfoBean() JG/sKOlA
{//nSplitter的缺省值为5 Dm 'Q&
//default value of nSplitter is 5 tp5]n`3rD
this("","","",5); !29 Rl`9
} D#(A?oN
4+v~{
.YS[Md{
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) c (\-7*En
{ HO' ELiZ_q
sSiteURL= sURL; 7F+f6(hB
sFilePath = sPath; cG"jrQ
sFileName = sName; D;Az>]>q
this.nSplitter = nSpiltter; WU=Os8gR
0CTI=<;
{Ziq~{W_
} W9eR3q
zaoZCyJT%
1 #EmZ{*
public String getSSiteURL() Ui?t@.
{ {?5EOp~
return sSiteURL; apw8wL2
} dX+DE(y
ss,6;wfX
Yt|{l
public void setSSiteURL(String value) ={zYcVI
{ ?dxhe7m
sSiteURL = value; [0J0<JnK
} 56TUh_
(F_#LeJ|
!sR`]0
public String getSFilePath() 2OK%eVba
{ XqJ@NgsY
return sFilePath; 6'qs=Ql
} :T'"%_d5
6J&L5E
4|Z3;;%+
public void setSFilePath(String value) <PfW
{ '9^x"U9c
sFilePath = value; ~~yo& ]
} E-!`6
MNJ$/l)h
fmloh1{4
public String getSFileName() wt)tLMEv
{ :r#FI".qx
return sFileName; ,T1t`
} N^`F_R1Z
k6*2= xK~
]2Lwd@
public void setSFileName(String value) ~Jq<FVK
{ uWMAXGL
sFileName = value; 8|i&Gbw+
} *+Q,b^N
U24?+/5D]
QEtZ]p1H@
public int getNSplitter() 4pA(.<#A
{ [nflQW6
return nSplitter; JY%c<
} c: #1Aym
!&19%C4
qY0GeE>N
public void setNSplitter(int nCount) )!M:=}."
{ 4d6F4G4U
nSplitter = nCount; @gs Kb*,
} FtE%<QHt
} (MbI8B>
*S{%+1F
6)DYQ^4y
/* z!t&zkAK
**Utility.java Z&/;6[
*/ VN;Sz,1Z
package NetFox; [\. ho9
Q0nSOTQ
rXfQ_
public class Utility { hv7!x=?8
knF *~O :y
:9K5zD
public Utility() 9j9A'Y9(
{ ~@L$}Eu
QbpRSdxy`$
<W\~A$
} k(hes3JV
GQ)hZt0
//线程睡眠 DA[-( s
public static void sleep(int nSecond) ?u 9) GJO[
{ #!9aTp).AL
try{ TvMY\e
Thread.sleep(nSecond); I)DLnnQQ
} 4$ejJaE
catch(Exception e) _Z5l Nu
{ j}S
e.printStackTrace (); v@"xEf1n[
} h^34{pKDn
} ^|as]x!sv
jlzqa7
//日志 *F~"4g
public static void log(String sMsg) )"|g&=
{ uXu'I
System.err.println(sMsg); 0qZ{:}`3
} -4Y}Y59\
wxr93$v
QQ1+uY
public static void log(int sMsg) #.a4}ya19
{ NfS0yQPx
System.err.println(sMsg); BI,K?D&W-
} rWi9'6
} Xp._B4g
B>#zrCD
u ldea)
/* BP*gnXj
**TestMethod.java M)Tv(7
*/ ~>xn9vb=
package NetFox; %NX
44RZk|U1J{
2%1g%
public class TestMethod { ;^O^&<
QH9(l
htlsU*x
public TestMethod() M1Od%nz3
{ ///xx/weblogic60b2_win.exe (Qq! u
try{ E=sBcb/v
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); RAXqRP,iw
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); pRUN[[L
SiteFileFetch fileFetch = new SiteFileFetch(bean); 0%`\8
fileFetch.start(); A{mbL2AxwC
} DU]MMR
catch(Exception e){e.printStackTrace ();} w0^(jMQe^
X f!Bsp#\g
k[y{&f,
} 1Qhx$If~
UQ`%,D
ch \*/
public static void main(String[] args) |3Oe2qb
{ }9<aX Y,
new TestMethod(); T*-*U/
} 3`IDm5
} vlp]!7v
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